Diesel engine d 12. Motor from the tank. Life in peacetime

Features of the Volvo D12S power unit
The engine of this model, used for completing trucks VOLVO (VOLVO) FM12, as well as FH12, has a volume of 12.1 liters. Depending on the modification, it can have a capacity of 340 (D12C340), 380 (D12C380), 420 (D12C420) or 460 (D12C460) l / s. It has a number of advantages such as:

10 percent more torque than the D12A powertrain it was based on. The number of revolutions of the crankshaft reaches from 1100 to 1700 rpm.
- Optimization of the geometry of the fuel combustion chamber.
- Equipment of the power unit with a preheater.
- Implementation of precise injection thanks to the EMS engine management system.
- Expansion of the zone of maximum torque by optimizing the valve timing.
- Equipped with an integrated brake compression mechanism.
Volvo D12S engine models produced from 1998 to 2005 are equipped with a system that cools the injected air, as well as unit injectors equipped with electronic control. Structurally, pistons can be made in two versions:

Articulated 2-element. The upper part of the product is made of high-strength steel, and the lower part is made of aluminum.
- Whole. The material for its manufacture is aluminum.
Two types of pistons are oil-cooled. Spraying of oil is made by means of a nozzle. These power units are big power and at the same time they are very economical.

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Starting from this stage, our specialists carefully check the quality of power units. After the cargo arrives at the company's warehouse, minders at the stands once again carry out incoming control. By contacting us, you are guaranteed to receive an engine that is in excellent condition, with a significant motor resource for an affordable price.

"D-120" is a two-cylinder four-stroke diesel engine with direct injection of diesel fuel and air cooling produced by the Vladimir Motor and Tractor Plant. These power units are known primarily as motors of the SSH-2540 self-propelled chassis (T-16, T-16M), as well as the Vladimirets tractors T-25, T-28, T-30", "KhTZ-2511".

In addition to these tractors, the D-12O engines in Soviet times were widely used on small-sized loaders (PUM-500, PUM-500M, DP-1604), welding units of the ADD type, at power plants (AD-8-T400-1VP , ED-8-T400-1VP), compressor stations "PKSD-1.75", etc. The motors have passed a solid test of time, over many decades, and have proven themselves to be unpretentious and reliable, easy to operate and maintain, quite economical diesel engines.

Previously, power units of modifications "D-12O-44" and "D-12O-45" were produced in Vladimir under the names "D-21" and "D-21A-1". From these. earlier models "D-12O-44" and "-45" are distinguished by a higher crankshaft speed and increased power.

The Vladimir Motor Tractor Plant is practically the same age as the great Victory: its first stage was built in 1944 and put into operation at the end of April 1945. At the same time, the Vladimir Tractor College (now the Polytechnic College) was opened to train specialists. The plant produced compact wheeled tractors, the most famous of which were the Vladimirets tractors -, T-25A, T-28, T-30.

Since the 1950s, production has also been mastered here. diesel engines, work was underway to improve their design. In 1962, for the first time in the domestic engineering industry, four-cylinder D-37M diesel engines were launched into mass production here.

During the Soviet era, tractors and diesel engines from Vladimir were exported to more than sixty countries of the world (the share of exports reached 40% of the total). in 1988, the plant produced its four millionth engine and one millionth tractor. The branches of the enterprise were two aggregate plants, a mechanical assembly plant and a plant for special tools and technological equipment, located in the city and the region.

Tractor "Vladimirets T-25".

In the post-perestroika era, the Vladimir Motor Tractor Plant continued, with varying success, to stay afloat until the 2010s. Here, in 1998, they launched the production of an updated "top-top" - a self-propelled chassis (in Soviet times, the "top-top" "T-16" was produced in Kharkov). In 2005, the thousandth such machine was produced. In the late 90s / early 2000s, they launched the production of new tractor models, featuring modern design and improved technical specifications: "VTZ-2000" ("VTZ-2O27", "VTZ-2O32"); "T-45", specially adapted for work in greenhouses; VTZ-2O63AS "Turbo-99" (60 hp); 80-horsepower tractor VTZ-2O8OAS Vityaz-2OOO; forklift "VTZ-3OSSH-PV"; "T-5O" (), "T-85" (class 1.4); communal machine "VTZ-3OSSH-K0". The production of engines did not stand still either: along with air-cooled diesel engines, they developed and introduced into production liquid-cooled engines, as well as economical methane engines. However, all these products, by and large, have not found their buyers in a market economy.

In the fall of 2017, the assets of the Tractor Plants concern, which included VMTZ, were transferred to the state corporation Rostec, which, together with a number of ministries, took up the “improvement” of these enterprises that were in a state of long-term crisis. The last employees of the plant - more than three hundred people were formally employed by transfer to the Cheboksary "Promtractor" and put out of service, receiving from 5 to 7 thousand per month. On July 20, 2018, all of them were fired due to redundancy, and the VMTZ enterprise was liquidated. Vladimir Motor Tractor Plant has joined a huge list of thousands of large enterprises Soviet period that ceased to exist in the 2000s.

Features of the design of the engine "D-120"

The main feature of this motor is, of course, the air cooling system. It greatly simplifies its maintenance and operation. No need to install a radiator, expansion tank and other elements that are indispensable for a liquid cooling system.

The engine is compact and relatively small, especially for diesel engines, mass. Also in the design of the D-120 diesel engine, an original balancing mechanism has found its application. It negates the vibration inherent in all two-cylinder engines. The specific fuel consumption is at the level of the best economic indicators for diesel engines, and the optimal layout on the equipment that “got” this engine makes maintenance and repair as convenient and affordable as possible.

Depending on the applicability and features of a particular purpose, D-12O diesel engines were produced in configurations with a nominal crankshaft speed of 2000, 1800 or 1500 rpm. In particular, in addition to the basic tractor configuration, these are:

The D120 diesel engine consists of the following components: a crank mechanism, a balancing mechanism and a gas distribution mechanism, a decompressor, a power supply system, lubrication and cooling, and electrical equipment.

The main part of the motor is the crankcase. In the bores of the crankcase there are two cylinders located vertically in a row, which are sealed with gaskets in the lower part. At the rear end of the crankcase is the flywheel housing, which power unit connected to the gearbox. At the front end of the engine there is a front sheet with a fuel pump and a timing gear cover installed on it. The lower part of the diesel crankcase is covered with an oil pan.

The crank mechanism creates the rotation of the crankshaft, with the help of a gas distribution system, while converting the movements of the pistons into energy. The engine crankshaft speed controller is centrifugal, all-mode with a fuel supply corrector. When the engine is running, the pressure of the gases converted from the combustion of diesel fuel acts on the pistons. Through the connecting rod, the force is transmitted to the crankshaft, which rotates from these forces. The flywheel reduces the imbalance of the diesel engine and transmits torque through the clutch to the tractor transmission.

In the axial direction, the crankshaft is fixed by half rings, which are installed in the bores of the middle crankcase partition and in the main bearing caps. The pistons are fitted with three compression rings. The oil scraper ring on the piston is one, combined. The combustion chamber is located in the bottom of the piston. The balancing mechanism equalizes the moment from inertial forces during the operation of the diesel engine. This mechanism consists of an additional roller with counterweights and special tides on the front pulley and diesel flywheel.

The roller rotates at the same speed as the crankshaft, but in the opposite direction. The drive is carried out from the timing gear through the intermediate and driven gears. The operation of the gas distribution mechanism must be synchronous with the supply of diesel fuel, and the gears are installed strictly according to the marks on the gears.

A decompressor is needed for easy starting of a diesel engine. In addition, the decompressor is used in emergency situations to stop the motor. The decompressor consists of a rail, two rollers and two levers, which are pivotally connected to the rail. The levers are rigidly connected to the rollers, and their ends enter the pushers intake valves. Moving the rack turns the levers with rollers, and the pushers rise, slightly opening the intake valves with the help of rods and rocker arms. In the off state, the pushers do not lift the rollers.

The mixture formation method is an undivided combustion chamber (a chamber in a piston), with direct injection of diesel fuel. The nozzles on the "D-12O" are installed of a closed type, with a multi-jet sprayer. Brand - "16.1112010", pinless. Diesel fuel coarse filter - mesh, with a replaceable filter cartridge. Fine filter - with a replaceable filter paper element. Air cleaner - inertial-oil.

The lubrication system of the D-12O diesel engine is combined: under pressure from the oil pump and spraying, with further cooling, in the oil cooler. The oil pump is gear-driven, driven by the crankshaft of the engine. For lubrication, motor oil "M-10G-2" and "M-10-V2" is used - in the summer, "M-8G2" and "M8-V2" - in the winter.

The cooling system of this engine is air, forced, with a guide vane, which is installed in the inlet of the cooling air flow; with an axial fan driven by a belt drive. Regulation of the thermal state of the diesel engine - forced, seasonal, by turning on / off the oil cooler, as well as using the throttle disc of the fan, which is installed in front of the guide vane. Thermal state control is carried out using control lamp, and there is an oil temperature gauge in the lubrication system.

The fuel pump is installed single-plunger distribution type "5З.11.11.ОО4", or two-plunger, type "2UTNM". The D-120 diesel engine is equipped with an SCH-102V hour meter.

Updated "top-top": self-propelled chassis "VTZ-3OSSH", with the engine "D-120", produced since 1998.

• Operating power: 15.4 kW (21 hp), or 18.4 kW (25 hp), or 22 kW (30 hp), depending on modification.
• Rated speed - 1500 ... 1800 ... 2000 rpm, respectively.
• Specific fuel consumption at rated power - 241 g/kWh (177 g/l.s.h.).
• Maximum torque - 103 N.m (10.5 kgf.m), or 104 N.m (10.6 kgf.m), or 113.4 N.m (11.55 kgf.m), depending on modifications.
• The nominal torque factor is 15 (-3, +10).
• The order of operation of the cylinders is 1-2-0-0.
• Cylinder diameter - 105 mm.
• The piston stroke is 120 mm.
• The working volume of the cylinder is 2.08 liters.
• The compression ratio is 16.5.
• Estimated valve timing: start of intake - 16 degrees before TDC; inlet end - 40 degrees after BDC; start of release - 40 degrees after BDC; end of release - 16 degrees after TDC.
• The relative oil consumption for waste is 0.3-0.5% of the diesel fuel consumption.
• Overall dimensions: length - 689 mm, width - 628 mm, height - 865 mm.
• Engine weight (unfilled, as delivered) - from 272 to 295 kg, depending on the configuration.

On secondary market presented a number of offers for the sale of both unused and used, or restored after overhaul diesel engines "D-120". The price for them varies from 60,000 to 130,000 rubles.

Specifications

Diesel engines of the 3D12, 3D12A type are designed for installation on ships for various purposes as the main marine diesel engines working on propeller.

These diesel engines are high-speed, four-stroke with direct fuel injection. Type 3D12A and type 3KD12N - twelve cylinders with a V-shaped arrangement of cylinders and a collapse of blocks 60 0. Diesel engines of the 3D12A type are manufactured with an aluminum crankcase. The rest are only with a cast-iron crankcase.

The cooling system is liquid, circulating, double-circuit, with separately located water-to-water and water-to-oil coolers and thermostats. An outboard water pump is installed on diesel engines to pump water through the external circuit of the cooling system.

Lubrication system - circulating, under pressure with a "dry" sump, with an electric pump for pre-start pumping of the system.

The diesels are equipped with a reverse gear, consisting of a gearbox and a hydraulically controlled multi-plate clutch designed to connect and disconnect the propeller from the crankshaft, as well as change the direction of rotation of the ship's propeller. Several models of each diesel engine are produced, differing in the direction of rotation of the output shaft of the reverse gear: right (clockwise) and left (counterclockwise), looking from the side of the reverse gear, as well as reduction to forward and reverse.

By order of consumers, to replace exhausted 3D12 and 3D12L diesel engines, they can be supplied without a reverse gear:
-3D12ABr - 310 hp at 1500 rpm left hand rotation c/c with cast iron crankcase for operation with reverse gear type Sb.1225-00-5 or Sb.525-01-13;
-3D12ALBr - 310 hp at 1500 rpm right-hand rotation a/c with a cast-iron crankcase for operation with a reverse gear type Sb.1225-00-5 or Sb.525-01-13;

It should be borne in mind that the reverse gear changes the direction of rotation of the output shaft (propeller) to the opposite.
Diesel engines can be equipped with an additional power take-off up to 30 hp. (PTO).
Diesel engines are started by an electric starter or compressed air. To charge the batteries, diesel engines are equipped with an alternator with a built-in rectifier, voltage regulator and radio interference suppression device.

Diesel engines can be controlled and controlled from the control panel directly on the diesel engine or from the control panel located in the ship's wheelhouse.

At the request of consumers for special vessels, diesel engines of the 3D12A, 3D12-1 and 3D12A-1 types can be supplied complete with the FK6501 system (diesel functional control device), which, with the mechanisms, devices and relays (sensors) installed on them, provides emergency warning and protection according to controlled parameters (overheating of the coolant and oil, oil pressure drop and “runaway”). These diesels have brands: 3D12AA, 3D12ALA, 3D12A-1A, 3D12AL-1A, 3D12-1A, 3D12L-1A.

Diesel engines meet the requirements of the Rules of the Russian Maritime Register of Shipping and the Russian River Register.

Direction of rotation (right or left); suction lift NZV (for 3KD12N-520); 3D6S2 and 3D12 type diesel engines with or without a reverse gear, with or without the APSiZ system, the presence of a PTO, as well as a Certificate of the Marine or River Register, is negotiated when placing an order (agreement).

Contents of delivery:
1. Accessory kit ( rechargeable batteries with connecting wires, water and oil coolers, thermostats) is specified when ordering;
2. Single set of spare parts;
3. Tool kit;
4. A set of operational documentation.

Victory" is usually understood as aircraft, tanks, artillery installations, sometimes small arms that have reached Berlin. Less significant developments are mentioned less often, but they also went through the whole war and made their important contribution. For example, the V-2 diesel engine, without which the T-34 tank would have been impossible.

For military and strategic products, as you know, the requirements are more severe than for "civilian" equipment. Since the real term of their service often exceeds thirty years - not only in Russia, but also in the armies of most countries.

If we are talking about tank engines, they, of course, must be reliable, undemanding to the quality of fuel, convenient for maintenance and some types of repairs in extreme conditions, with a resource sufficient by military standards. And at the same time regularly issue basic characteristics. The approach to designing such engines is special. And the result is usually decent. But what happened to the V-2 diesel is a phenomenal case.

Painful birth

His life began at the Kharkov Locomotive Plant named after. Comintern, the design department of which in 1931 received a state order for a high-speed diesel engine for tanks. And it was immediately renamed the diesel department. The task stipulated a power of 300 hp. at 1600 rpm, despite the fact that for typical diesel engines of that time, the operating speed of the crankshaft did not exceed 250 rpm.

Since the plant had not done anything like this before, they began development from afar, with a discussion of the scheme - in-line, V-shaped or star-shaped. We settled on the V12 configuration with water cooling, electric start and Bosch fuel equipment - with a further transition to a completely domestic one, which also had to be created from scratch.

First, a single-cylinder engine was built, then a two-cylinder section - and it was debugged for a long time, having achieved 70 hp. at 1700 rpm and a specific gravity of 2 kg/hp. A record low specific gravity was also stipulated in the task. In 1933, a workable, but unfinished V12 passed bench tests, where it constantly broke down, smoked terribly and vibrated strongly.

The V-2 engine in its original form spent more than 20 years in mass military service. Individual copies are still on the move. A few more found peace in various museums.

The test tank BT-5, equipped with such an engine, could not reach the test site for a long time. Either the crankcase cracked, or the crankshaft bearings collapsed, or something else, and to solve many problems, it was necessary to create new technologies and new materials - first of all, grades of steel and aluminum alloys. And buy new equipment abroad

Nevertheless, in 1935, tanks with such diesel engines were presented to the government commission, additional workshops were erected at the KhPZ for the production of engines - the “diesel department” was transformed into a pilot plant. In the process of fine-tuning the motor, its secondary purpose was taken into account - the possibility of using it on aircraft. Already in 1936, the R-5 aircraft with a BD-2A diesel engine (the second aviation high-speed diesel engine) took to the air, but this engine was never in demand in aviation - in particular, due to the appearance of more suitable units created by specialized institutes in the same years.

In the main, tank direction, things progressed slowly and heavily. Diesel still ate too much oil and fuel. Some parts regularly broke down, and too smoky exhaust unmasked the car, which was not particularly liked by the customers. The development team was reinforced by military engineers.

In 1937, the engine was named V-2, under which it entered the world. And the team was strengthened once again by the leading engineers of the Central Institute of Aviation Motors. Part technical problems entrusted to the Ukrainian Institute of Aircraft Engine Building (later it was attached to the plant), which came to the conclusion that it was necessary to improve the accuracy of manufacturing and processing parts. Own 12-plunger fuel pump also required fine-tuning.

In state tests in 1938, all three second-generation V-2 engines failed. The first had a jammed piston, the second had cracked cylinders, the third had a crankcase. Based on the test results, almost all technological operations were changed, the fuel and oil pumps were changed. This was followed by new tests and new changes. All this went in parallel with the identification of "enemies of the people" and the transformation of the department into a huge State Plant No. 75 for the production of 10,000 motors per year, for which hundreds of machine tools were imported and assembled.

In 1939, the engines finally passed state tests, receiving a “good” rating and approval for mass production. Which was also debugged painfully and for a long time, which, however, was interrupted by the hasty evacuation of the plant to Chelyabinsk - the war began. True, even before that, the V-2 diesel engine was baptized in real military operations, being installed on heavy KV tanks.

What happened?

The result was a motor, about which they would later write that, in terms of design, it was far ahead of its time. And for a number of characteristics, for another thirty years, it surpassed analogues of real and potential opponents. Although it was far from perfect and had many areas for modernization and improvement. Some army technology experts believe that the fundamentally new Soviet military diesel engines, created in 1960-1970, were inferior to the B-2 family diesel engines and were put into service only for the reason that it was already indecent not to replace the "obsolete" with something modern.

The cylinder block and crankcase are made of an alloy of aluminum with silicon, the pistons are made of duralumin. Four valves per cylinder, overhead camshafts, direct injection fuel. Duplicated starting system - electric starter or compressed air from cylinders. Almost all technical description- a list of advanced and innovative solutions of the time.

It turned out to be ultra-light, with an outstanding specific gravity, economical and powerful, and the power was easily varied by local changes in the operating speed of the crankshaft and compression ratio. Even before the start of the war, there were three versions in constant production - 375-, 500- and 600-strong, for equipment of different weight categories. Having fitted the supercharging system from the AM-38 aircraft engine to the B-2, they received 850 hp. and immediately tested on an experimental heavy tank KV-3.

As they say, any more or less suitable mixture of hydrocarbons could be poured into the tank of a car with a motor of the V-2 family, starting from household kerosene. It was a strong argument in the conditions of a difficult protracted war - dilapidated communications and the difficulty of providing everyone with everything necessary.

At the same time, the motor did not become reliable, despite the requirements of the People's Commissar of the Tank Industry V.A. Malyshev. It often broke down - both at the front and during various tests during the war years, although from the beginning of 1941 engines of the “fourth series” were already being produced. Summed up and design miscalculations, and violations of manufacturing technology - largely forced, because there were not enough necessary materials, they did not have time to renew worn-out equipment, and production was debugged in a wild hurry. It was noted, in particular, that dirt “from the street” gets into the combustion chambers through various filters and the warranty period of 150 hours in most cases is not maintained. Whereas the required diesel resource for the T-34 tank was 350 hours.

Therefore, modernization and "tightening the screws" went on continuously. And if in 1943 the normal service life of the motor was 300-400 km, then by the end of the war it exceeded 1200 km. And the total number of breakdowns was reduced from 26 to 9 per 1000 km.

Plant No. 75 could not cope with the needs of the front, and factories No. 76 in Sverdlovsk and No. 77 in Barnaul were built, which produced the same B-2 and its various versions. The vast majority of tanks and part of the self-propelled guns that participated in the Great Patriotic War were equipped with the products of these three factories. The Chelyabinsk Tractor Plant produced diesel engines for the medium tank T-34, heavy tanks of the KV series, light tanks T-50 and BT-7M, and the Voroshilovets artillery tractor. On the basis of the V-2, the V-12 was developed, later used in the IS-4 tanks (he managed to fight for about a month) and the T-10.

Life in peacetime

The full potential of the V-2 design could not be revealed either before or during the war - there was no time to engage in unlocking the potential. But a set of various minor imperfections turned out to be an excellent basis for development, and the concept itself was optimal. After the war, the family was gradually replenished with tank engines V-45, V-46, V-54, V-55, V-58, V-59, V-84, V-85, V-88, V-90, V-92 , V-93 and so on. Moreover, the development has not yet been completed, and individual motors of the family are still mass-produced.

The T-72 tank - the main battle tank of the USSR, produced in a circulation of about 30 thousand copies, received a 780-horsepower B-46 engine. The modern main battle tank of Russia T-90 was originally equipped with a 1000-horsepower supercharged B-92 engine. Many of the theses of the descriptions of the B-2 and B-92 are completely the same: four-stroke, V-shaped, 12-cylinder, multi-fuel, liquid cooling, direct fuel injection, aluminum alloys in the cylinder block, crankcase, pistons.

For infantry fighting vehicles and other less heavy equipment, they created an in-line half-motor from the B-2, and the first developments of such a scheme were carried out and tested in 1939. Also among the direct descendants of the V-2 is a new generation of X-shaped tank diesel engines produced by ChTZ (used on the BMD-3, BTR-90), which use halves in another dimension - the V6.

He was also useful in the civil service. In the Barnaultransmash association (former plant No. 77), an in-line D6 was created from V-2, and later a full-size D12. They were put on a lot of river boats and tugboats, on motor ships of the Moscow and Moskvich series.

The shunting diesel locomotive TGK2, produced with a total circulation of ten thousand copies, received a modification of 1D6, and 1D12 was put on mining trucks MAZ. Heavy tractors, locomotives, tractors, various special machines - wherever a powerful reliable diesel engine was required, you will find the closest relatives of the great B-2 engine.

And the 144th Armored Repair Plant, which was part of the 3rd Ukrainian Front from Stalingrad to Vienna, still offers services for the repair and restoration of B-2 type diesel engines. Although it has long since become a joint-stock company and settled in Sverdlovsk-19. And frankly, I can’t believe that high overall power, reliability and reliability in operation, good maintainability, convenience and ease of maintenance modern motors this family is just an advertising barker. Most likely, the way it really is. For which thanks to everyone who created and improved this long-lived motor.

Engine BelAZ D12A-375B

The high-speed four-stroke diesel engine D12A-375B has two cylinder blocks arranged in a V-shape at an angle of 60°.

Crankcase and cylinder blocks

The engine crankcase is cast, consists of the upper and lower parts, interconnected by means of studs and four fitting bolts. The plane of the connector is sealed with a thread of natural silk or nylon and smeared with "sealant" paste.

Tie rods are screwed into the upper part of the crankcase, which connect the blocks and cylinder heads to the crankcase.

The lower part of the crankcase acts as an oil sump; in the front part, the engine oil and water pumps are mounted on it.

Rice. 1. Engine D12A-375B:
1 - oil filter; 2 - oil pump; 3 - water pump; 4 - drive pulley for fans and compressor drive; 5 - tachometer sensor; 6 - cylinder head cover; 7 - hatches in the cover; 8 - exhaust gas pipe; 9 - exhaust pipelines; 10 - inlet pipelines; 11—fuel pre-filter; 12 - beam of the front engine mount; 13 - generator

Rice. 2. Block and cylinder head:
1 - cylinder head cover; 2 - platform for installing a tachometer sensor; 3 - bearings camshafts; 4 - cylinder head; 5 - drive shaft bracket; c - hole for supplying oil; 7 - holes (wells) for tie rods; 8 - sockets for installing nozzles; 9 - valve guides; 10 - channel for draining oil; 11 - bypass hole for water; 12 - valve seat; 13 - sealing gasket; 14 - cylinder block; 15 - water supply pipe; 16 - cylinder liner; 17 - sealing rubber rings (3 pcs.); 18 - windows for the passage of water; 19 - control holes of the block

The left and right cylinder blocks have 14 holes for the passage of tie rods, six easily removable steel cylinder liners and internal cavities through which water circulates, cooling the liners.

The order of numbering of the engine cylinders is shown in fig. 3.

Cylinder liners in the lower part are sealed with rubber rings made of heat-resistant rubber. The top two rings are rectangular and the bottom ring is round. The upper part of the sleeve is sealed due to the exact fit of its flange on the recess in the cylinder block.

Holes (wells) for the passage of tie rods along the upper plane of the cylinders are sealed with rubber rings. In the lower part, the cylinder blocks have control holes that come from the wells and serve to control the absence of water or oil in the wells.

On the upper plane of each block and the lower plane of the head there are holes for the passage of coolant from the blocks to the cylinder heads. By-pass tubes with rubber rings for sealing are inserted into the holes.

Cylinder heads - aluminum, fastened along the perimeter with sewn-in studs to the blocks, together with which they are attached to the crankcase with tie-down studs. Flat sealing washers are installed under the nuts of the tie rods; which completely block the holes, preventing oil leakage from the upper plane of the cylinder head.

On the side planes of the cylinder heads of the engine are the inlet and outlet channels of the cylinders.

On the mounting side of the intake manifold, six cap nuts are screwed into the cylinder head for installing the start valves of the air intake system.

Aluminum gaskets are installed between the blocks and cylinder heads, sealing the combustion chambers.

Camshafts and a valve mechanism of the gas distribution system, closed by covers, are installed on the upper planes of the cylinder heads.

After the first 100 hours of operation of a new engine, it is necessary to check the tightness of the nuts securing the intake and exhaust pipelines of the engine. In the future, the nuts are tightened only if necessary.

After the first 500 hours of operation of the new engine, the tightness of the nuts of the tie-down and tie-down studs of the cylinder blocks is checked. In the future, the nuts are tightened only if necessary.

Timely tightening of the tie rod nuts and tie rod nuts prevents damage to the cylinder head gasket by eliminating gaps resulting from loosening the nuts from vibration or from changing linear dimensions details.

To tighten the tie rod nuts, remove the high pressure fuel lines, fuel pre-filter and cylinder head covers from the engine. The open ends of the fuel lines are covered with clean oiled paper or electrical tape to protect them from dust and dirt.

Rice. 3. The layout of the engine cylinders:
1 - left cylinder block; 2 - right block of cylinders; 3 - flywheel

Rice. 4. Tie stud nut tightening sequence

The tightness of the nuts of the tie rods is checked by tightening them with a wrench with a handle length of 1000 mm with a force created by one person in the order indicated in fig. 4.

Nuts that can be tightened are tightened at one time by no more than half a face, and in total by no more than one face.

After fully tightening, all nuts, together with the studs, are unscrewed by 3-5 ° (face offset by 1-1.5 mm) to eliminate the torsional stress in the studs.

The tightening of the nuts of the sewing studs is checked with a wrench with a handle length of 125 mm by tightening them to failure, starting with the first right nut on each block, going around the block counterclockwise.

crank mechanism

The crankshaft is steel, stamped, equipped with a torsional vibration damper. The shaft has six cranks located in three planes at an angle of 120° to each other, seven main (support) and six connecting rod journals. Indigenous and connecting rod bearings equipped with easily removable inserts.

At the front end of the crankshaft, a drive gear of the gear mechanism is installed, from which, by means of gear gears, power is taken to the following units and mechanisms: along the upper vertical shaft - to the high-pressure fuel pump and air distributor, along two inclined shafts - to the gas distribution mechanisms, along a separate inclined shaft - generator, along the lower vertical shaft - to the fuel-priming, water and oil pumps.

The direction of rotation of the crankshaft is clockwise (right), as viewed from the gear mechanism.

The connecting rods of the left and right blocks have a common crankpin and a common bearing. The connecting rod installed in the left block, when viewed from the side of the gear mechanism, is the main one, and the connecting rod of the right block is trailed. The trailing connecting rod is attached to the main connecting rod with a hollow pin fixed in an eye on the lower head of the main connecting rod.

The upper heads of the connecting rods are equipped with tin bronze bushings. The lower head of the main connecting rod is detachable, equipped with liners made of steel-aluminum strip or steel, filled with lead bronze. From turning, the liners are fixed with pins.

The pistons, stamped from aluminum alloy, are attached to the connecting rods with the help of hollow floating-type pins, fixed from axial movements with aluminum plugs 5.

The piston crown serves as the lower part of the combustion chamber and is specially shaped. Along the edges of the bottom there are four flat recesses, into which the inlet and outlet valves enter when the piston approaches the c. m. t.

Each piston has two compression rings and three oil scraper rings, one of which is located below the pump (0.786 p) of the piston pin.

Rice. 5. Diagram of the engine gear mechanism:
1 - drive to the generator (1.5 "); 2 - drive to the air distributor; 3 - drive, to the fuel pump; 4 - roller oil pump(1.725 p); 5 - transfer to fuel pump-

Compression rings - steel, the working surface is covered with a layer of chromium and tin. Oil scraper rings - cast iron, have a conical shape and are installed on the piston with a smaller cone diameter upwards. For correct installation new rings on the side of the smaller diameter have the inscription "top".

The condition of the engine piston rings, if necessary, is checked by measuring the gas pressure in the crankcase using a water piezometer (pressure gauge), connecting it to the cover of the upper engine crankcase hatch, having previously disconnected the oil drain pipe from the high pressure pump housing from the cover. For the time of measuring gas pressure, it is necessary to shut off the oil supply to the pump by unscrewing the fitting that secures the oil line to the pump, and install a wooden plug in the elbow of this pipeline.

The gas pressure in the crankcase of a new engine should be no more than 80 mm of water. Art., after 1000 hours of engine operation - no more than 100 mm of water. Art.

Gas distribution mechanism

The gas distribution mechanism is an overhead valve with a direct valve drive from the camshafts.

Valves. Each cylinder has two intake and two exhaust valves (Fig. 14). The plate is screwed into the rod and locked with a lock. The holes on the side surface of the lock are designed to release the lock with a special fork when adjusting the gap between the valve plate and the back of the camshaft cam. The clearance is adjusted by screwing into the stem or turning out of the valve stem from the stem.

The camshafts rotate in aluminum alloy bearings, which are lubricated through cavities and holes in the shafts.

The intake camshafts are located on the inside of the engine, the exhaust valves on the outside.

The special design of the camshaft drive gear mount allows you to change its position when adjusting the valve timing. The drive gear from axial movements is stopped by an adjusting sleeve, which with its outer splines enters the splines of the gear, and with its internal splines it is connected to the splines on the camshaft. At the same time, the adjusting sleeve is in constant engagement with the nut due to the split spring ring inserted between them.

Rice. 6. Connecting rod and piston group:
1 - piston; 2 - compression rings; 3 - oil scraper rings; 4 - piston pin; 5 - plug of the piston pin; 6 - main connecting rod; 7 - trailer connecting rod; 8 - pin of the trailer connecting rod; 9 - locating pin; 10 - cover); 11 - locating pin of the insert; 12 - insert; 13 - hole for supplying lubricant to the pin of the trailer connecting rod; 14 - conical pin

When screwing or unscrewing, the adjusting sleeve moves along with the nut, which respectively engages or disengages with the splines of the gear and shaft. The nut is locked with a ring that fits into the groove at the end of the adjusting sleeve and into the hole in the nut. Nuts for intake camshafts are left-handed, exhaust camshafts are right-handed.

The meshing of the camshaft drive bevel gears is adjusted at the factory and kept constant by a carefully matched setting ring.

After the first 500 hours of operation of a new engine, check the tightness of the nuts of the camshaft adjusting sleeves, and then tighten the nuts only if necessary.

The tightness of the nuts is checked in the following sequence. Carefully remove the split retaining rings 6 and tighten the nuts 7 with a special wrench to failure. The intake camshaft nuts (left-hand thread) are tightened counterclockwise, the exhaust camshaft nuts (right-hand thread) are tightened clockwise.

After tightening the nuts, install the removed retaining rings in their places so that when the camshafts rotate, they rotate towards each other with radial antennae. Deformed rings are carefully aligned before installation.

When repairing the engine, in case of replacement of parts of the gas distribution mechanism or gear mechanism, as well as in case of removal of cylinder heads, full check and gas distribution adjustment, i.e., they check the compliance of the opening and closing moments of the intake and exhaust valves with the valve timing diagram of the engine.

Rice. 7. Valves:
a - graduation; b - inlet; 1 - plate; 2 - lock; 3 - rod; 4 - springs

Rice. 8. Camshaft Gear Mount:
1 - spring ring; 2 - double gear; 3 - camshaft; 4 - adjusting ring; 5 - adjusting sleeve; 6 - retaining ring; 7 - camshaft nut; 8 - plug

Periodically, after 1000 hours of engine operation, the valve timing is checked only by the gaps between the camshaft cams and valve plates. Checking and adjusting the valve timing is performed on a cold engine. The crankshaft of the engine is manually turned with a wrench at the rear end of the input shaft of the matching gearbox with the rear cover of the matching gearbox removed.

When checking and adjusting the valve timing, they are guided by the following data:
inlet start 20 ± 3° to v. m.t. on the exhaust stroke;
inlet end 48 ± 3° a.s.l. m.t. on the compression stroke;
beginning of release 48 ± 3 ° BC. m.t. (expansion cycle);
outlet end 20 ± 3° a.s.l. m.t. on the intake stroke;
intake and exhaust duration 248 °;
gap between the backs of the cams and valve plates 2.34 ± 0.1 mm;
Cylinder order:
1 l -6p-5l-2p-Zl-4p-6l- 1 p-2l-5p-4l-Zp.

The shift of the same phases of two adjacent cylinders in the order of operation is equal to 60 ° of rotation of the crankshaft.

A clear picture of the order of operation of the engine cylinders and the initial data on adjustment is given by the diagram shown in fig. 9, which shows the position of the pistons and valves of the engine for all cylinders depending on the angle of rotation of the crankshaft.

To check and adjust the valve timing directly on the car, there are divisions on the flywheel flange and an arrow pointer on the flywheel housing cover.

Before checking the valve timing, the fuel supply advance angle and the installation of the air distributor, it is necessary to check the position of the pointer on the flywheel housing cover. At the bottom of the housing cover and on the flywheel housing, after the pointer is set to the desired position, installation marks are applied at the factory, which must always match. If the alignment marks do not match, unscrew the bolts securing the flywheel housing cover and turn the cover until the marks are aligned.

To set the piston of the cylinder under test to the required position, align the corresponding division on the graduated flywheel flange with the pointer arrow.

Rice. 10. Diagram for adjusting the valve timing (view from the flywheel side of the engine)

Rice. 11. Graduation of the flywheel flange:
1 - marks on the cover and flywheel housing; 2 - arrow pointer; 3 - cover fastening bolts; 4 - casing cover; 5 - graduated flywheel flange

When checking and adjusting the valve timing, it is very important to accurately determine the moment of opening and closing the valves, i.e., it is necessary to determine the moment the cam is pressed on the valve plate and the moment the cam stops pressing on the valve plate. These moments can be determined by turning the valve by hand on the plate: an open valve rotates a small angle in both directions with a slight effort, a closed one cannot be turned due to its friction against the seat. This moment can also be determined using a probe (strip of foil) with a thickness of 0.03-0.04 mm, laid on the plane of the plate: clamping the probe indicates the beginning of the valve opening, releasing the probe indicates the complete closing of the valve. Due to the fact that the intake and exhaust valves of the same cylinder must open and close at the same time, the test is carried out on two valves at once.

Check and adjust the valve timing in the following sequence.

Remove the head covers from both engine blocks, prepare the engine for turning the crankshaft by hand and check that the alignment marks on the cover and flywheel housing match. Check and, if necessary, adjust the gaps between the backs of the cams and the valve plates.

The gaps are checked on a cold engine with a feeler gauge in the order of operation of the cylinders, starting from the 1 liter cylinder. The crankshaft is rotated in the direction of its rotation when the engine is running until the backs of the cams of the intake or exhaust camshafts are set against the valve plates of the corresponding cylinder.

If it turns out that the gap does not correspond to the required value, press the plate lock with a fork and, screwing or unscrewing the valve plate using special tongs, adjust the gap. Having adjusted the valve clearances of 1 liter of the cylinder, the remaining valves should be adjusted in the order of operation of the cylinders.

Check the valve timing, i.e. the opening and closing angles of the intake and exhaust valves, starting with the 1 liter cylinder in the following sequence.

Rotating the crankshaft along the course, set it to a position of 40-50 ° to c. m. t. 1l of the cylinder on the exhaust stroke (exhaust valves are open).

Slowly rotating the crankshaft with a feeler gauge or turning the valve plate, determine the moment of opening the inlet valves of the 1st cylinder.

Rice. 12. Check clearances in the valve mechanism

If the angle does not correspond to the adjustment data, by rotating the crankshaft in the course, set it 20 ± 3 ° to the crank. m. t. 1l of the cylinder on the exhaust stroke (exhaust valves are open).

Loosen the nut (left-hand thread) and remove the left-hand intake camshaft adjusting sleeve.

With light blows of a lead or copper hammer, turn the camshaft and set the cams of the 1 liter cylinder to the position where the intake valves begin to open.

Put the adjusting sleeve in place, choosing a position in which the splines on the sleeve freely connect with the splines of the shaft and gear.

Again, check the beginning of the opening of the inlet valves of the 1l cylinder.

If there is a deviation, repeat the adjustment. If the result is satisfactory, tighten the nut of the adjusting sleeve, install the retaining ring.

Determine the closing moment of the exhaust valves of the 1 liter cylinder using a feeler gauge or by turning the valve disc.

If the angle does not correspond to the adjustment data, it is necessary to make an adjustment, as in the case of setting the opening angle of the intake valves. In this case, it should be noted that the nut of the adjusting sleeve of the exhaust shaft has a right-hand thread.

Rotating the crankshaft along the course, determine the moment of opening the inlet valves of the BPR cylinder (the sixth cylinder of the right block). The opening angle of the intake valves along the graduated flywheel flange must be 40 ± 3°. Then determine the closing angle of the exhaust valves of the same cylinder (should be 80 ± 3°).

If the angles do not correspond to the required values, the adjustment of the valve timing for the right block is performed similarly to the adjustment for the left block.

Check the valve timing for all other engine cylinders against the marks on the graduated flywheel flange to ensure that the valve timing is set correctly for the 1L and BPR cylinders.

Record the adjustment data in the engine log and install the cylinder head covers, high pressure fuel lines, matching gearbox cover in their places.

When checking and adjusting the valve timing, the following patterns must be taken into account.

The duration of the phase does not change when it is adjusted by rearranging the camshaft and adjusting sleeve. In this case, the earlier opening of the valve causes its earlier closing by the same degree.

Rice. 13. The position of the cams of the camshafts at the moment when the piston of the 1l cylinder is in c. m.t. exhaust stroke (view from the gear mechanism):
a - left block; b - right block; 1 - exhaust valves; 2 - intake valves

The duration of the phase changes when it is adjusted by changing the gap between the back of the cam and the valve seat. In this case, an earlier opening of the valve causes a later closing of the valve by the same degree.

The start or end of the valve timing must only be set at the corresponding engine stroke. Setting the start or end of a phase on the wrong stroke can cause the valves to bend when starting the engine.

When installing cylinder heads on an engine after repair, in order to avoid pistons meeting with open valves, it is necessary to install camshafts in the position indicated in fig. 14.

Rice. 15. Engine fuel supply system:
1 - fuel tanks; 2 - filling neck; 3 - tank deflection valve; 4 - fuel pre-filter; 5 - fuel priming pump; 6 - final fuel filter; 7 - plugs of holes for air release from fuel system; 8 - valve for emergency shutdown of the fuel supply; 9 - high pressure fuel pump; 10 - nozzles; 11 - fuel lines for draining fuel from injectors; 12 - fuel line of the integrated air exhaust system during engine operation; 13 - container for collecting fuel; 14 - drain plug; 15 - fuel level sensor; 16 - starting heater engine

Engine fuel supply system

The scheme of the engine fuel supply system is shown in fig. 20.

The fuel tanks are mounted on a bracket behind the driver's cab and are connected to each other by two hoses. The lower hose is used for the flow of fuel, and the upper hose is used to equalize the pressure inside the tanks when the fuel level changes.

On the right (in the direction of the car) tank there is a filler neck, fuel is taken from the same tank.

Periodically, after 500 hours of engine operation, the sludge is drained from the fuel tanks and the tanks and pipelines are washed with fuel (to remove deposits).

The fuel pre-filter consists of a welded cylindrical housing, in which a set of mesh filter elements is mounted on a tubular rod. The cavities of the cleaned and uncleaned fuel are separated by felt sealing rings.

Periodically, after 100 hours of engine operation, the filter is disassembled and washed in the following sequence.

Close the valve on the fuel line for taking fuel from the tank. Unscrew the nut on the bottom of the filter and remove the housing together with the filter elements. Remove the filter elements from the housing, rinse them in a clean diesel fuel, blow with compressed air. Rinse and clean the filter housing. Install the lower sealing ring 6, filter elements and the upper ring into the housing. Fasten the housing to the filter cover, paying attention to the presence of rubber sealing rings. open faucet fuel tank, start the engine and check the filter for fuel leaks.

Rice. 16. Fuel prefilter:
1 - cover; 2 and 7 - rubber sealing rings; 3 and 6 - felt sealing rings; 4 - body; 5 - mesh filter elements; 8 - coupling nut

Rice. 17. Fuel priming pump:
1 - adjusting screw; 2 - floating finger of the rotor; 3 - rotor blade; 4 - rotor; 5 - rotor glass; 6 - bypass valve; 7 - pressure reducing valve

The fuel priming pump (Fig. 22) is designed to supply fuel from the tank to the high pressure fuel pump through the final fuel filter.

A cup with an eccentrically bored hole is installed in the pump housing.

Inside the glass, coaxially with its outer surface, a rotor rotates with four longitudinal slots for the blades freely inserted into the slots. The blades rest on a floating finger and on the inner surface of the glass.

Due to the eccentric location of the rotor relative to the inner surface of the cup during rotation, the blades either move out of the grooves under the action of centrifugal force, or under the action of eccentricity they are pushed back, tightly adhering to the eccentric surface of the cup.

In this regard, when the rotor rotates, a vacuum is formed in the cavities between the blades and fuel is sucked into the cavity. With further rotation of the rotor, the volume of these cavities decreases, the fuel is displaced from the cavities and injected into the system.

The booster pump has a capacity that exceeds the fuel consumption of the engine. Therefore, in order to transfer part of the injected fuel from the injection chamber to the suction chamber, a pressure reducing valve is installed on the pump, adjusted to a pressure of 0.6-0.8 kg/cm2. The valve is adjusted with a screw acting on the valve spring. After adjustment, the screw is fixed with a cap.

In addition to the pressure reducing pump, it has a bypass valve, which, through the holes in the flange of the pressure reducing valve, ensures that the fuel system is filled before starting the engine when the fuel priming pump is not working.

The pump drive shaft is sealed with two rubber seals. To control the technical condition of the glands, there is a control hole on the plug screwed into the pump housing, the leakage of fuel or oil from which indicates a violation of the tightness of the glands.

The condition of the pump shaft seals is checked daily by inspecting the inspection hole.

The final fuel filter ensures the final purification of the fuel before it enters the plunger pairs of the high pressure pump.

The filter consists of a set of felt filter plates with inlet and outlet cardboard spacers between them. The filter plates are put on a cylindrical mesh frame, covered with a silk (kapron) cover.

On the filter cover there are fittings for supplying and discharging fuel, a fitting for the combined air exhaust system from fuel pump and from the cavity of the purified fuel of the filter, as well as the air release plug from the cavity of the unclean fuel.

Periodically, after 500 hours of engine operation, the filter is disassembled and washed in the following sequence.

Unscrew the nut on the cover, remove the housing together with the filter element. The filter element is removed from the housing and washed in diesel fuel without disassembly.

The filter element is disassembled in the following sequence: the pressure plate is removed, all spacers and felt filter plates are removed one by one from the mesh frame. The silk cover is not removed from the frame.

Rinse all parts of the filter in clean diesel fuel, clean and rinse the housing. Felt plates are first pressed by hand, and then they are folded two or three pieces together and squeezed between two wooden or metal plates.

‘Assemble the filter element in the following sequence.

The inlet spacer (with external windows), the filter plate (the darker side to the inlet spacer, which it was in contact with it before disassembly), the outlet spacer are put on the mesh frame, and the entire package is assembled in the same order. In this case, the protrusions on the outer diameter of the input and output spacers are located in the same plane.

If the assembled filter element is not tight enough, plates and spacers from the individual spare parts kit are added to it, after which the pressure plate is installed and the coupling nut is wrapped.

A spring and an oil seal are installed in the housing, and then the assembled filter element is installed in the housing with the nut down and the housing is fixed on the cover.

After disassembling and washing the filter, pump the fuel system to remove air, and then, starting the engine, check the filter for fuel leaks.

The emergency fuel shutoff valve is designed to automatically stop the engine in the event of an oil pressure drop in the main engine oil line below 2.5 kg / cm2, i.e. when damage to highly loaded rubbing engine parts (primarily crankshaft bearings) is possible due to lack of oil. In addition, the valve makes it impossible to start the engine without first supplying oil to the system using an oil pump, which reduces wear on parts when starting the engine.

Rice. 18. Final fuel filter:

The valve is mounted on the front end (drive side) of the high pressure pump housing. A fuel line from the final fuel filter and an oil line from the main oil line come to it.

In the absence of pressure in the oil pipeline, as well as at a pressure below 2.5-2.7 kg / cm2, the valve spool is pressed by a spring to the extreme right position, the holes on the body and spool are displaced and the fuel passage to the pump is blocked.

When the oil pressure is above 2.5-2.7 kg/cm2, the valve spool moves to the extreme left position under the action of oil pressure, compressing the spring, the holes in the body and spool are aligned and the fuel freely passes to the plunger pairs of the high pressure pump. The tight fit of the end collar on the spool to the body prevents the penetration of oil into the fuel.

The spool and its body are precision-manufactured parts and cannot be replaced individually. When checking the serviceability of the valve with the spring removed, the spool must move to the extreme positions under the action of its own weight.

Rice. 19. Emergency shutdown valve for fuel supply:
1 - housing of the high pressure fuel pump; 2 - adjusting nut; 3 - spool spring; 4 - spool; 5 - spool body; 6 - ball valve for separating oil and fuel cavities; 7 - seal; 8 - oil pipeline; 9 - fuel line

The valve actuation pressure is adjusted by tightening the spring with a nut.

The high pressure fuel pump is designed to supply precisely metered portions of fuel to the injectors under high pressure, depending on the engine load and the order of operation of the cylinders.

The fuel pump is a plunger type, with a constant stroke of the plungers. It is installed on three brackets on the horizontal platform of the upper part of the crankcase between the cylinder blocks, is fixed from longitudinal movement by a locking plate, which is included in the transverse groove on the pump housing and in the groove of the middle bracket, and is driven through the drive from the engine crankshaft.

There are two cavities in the fuel pump housing: a camshaft is installed in the lower one, and pump elements are placed in the upper one - plungers with sleeves and a common gear rack.

The camshaft rotates in two ball and five sliding bearings and has 12 cams, which transmit the movement of the plungers upward through the pushers.

The downward movement of the plungers is carried out by springs pressing the plunger plates against the pushers. The cam shaft is driven through a clutch with a textolite washer. It rotates counterclockwise when viewed from the drive end. The order of operation of the pump sections (numbering from the drive): 2-11 - 10-3-6-7-12-1-4-9-8-5. The interval between the start of fuel supply by pump sections is 30° in terms of the angle of rotation of the pump shaft (60° in terms of the angle of rotation of the engine crankshaft).

The odd sections of the pump supply fuel to the cylinders of the right engine block (from the drive side), the even sections - to the cylinders of the left block.

The fuel priming section of the pump is shown in fig. 21. Two radial holes a and b connect the inner cavity of the sleeve with the inlet channel into which fuel flows from the filter. When the plunger is in the lower position, both holes are open and the sleeve cavity is filled with fuel. The fuel supply begins from the moment the upper edge of the plunger overlaps the sleeve holes. At this moment, the fuel pressure in the space above the plunger begins to increase sharply, as a result of which the pressure valve, loaded with a spring, opens and fuel begins to flow to the nozzle.

When a pressure of 210 kg/cm2 is reached, the fuel lifts the needle that closes the injector outlet and is injected into the combustion chamber.

The injection of fuel into the cylinder stops as soon as the cut-off oblique edge on the plunger opens the sleeve hole. After that, the fuel does not enter the nozzle, but is bypassed through the longitudinal groove on the plunger back into the supply cavity.

Due to the presence of a relief belt on the discharge valve, when the valve is seated in the seat, the volume of the discharge cavity increases. As a result, the pressure in the pipeline decreases. The nozzle needle quickly sits in the saddle in the atomizer, which gives a sharp end to the injection. When the plunger moves down, the holes in the sleeve open and the cavity of the sleeve is again filled with fuel. The greater the distance from the upper edge of the plunger to the cut-off oblique edge, the later the cut-off occurs and the more fuel is supplied. The amount of fuel pumped into the cylinders is regulated by shifting the end of the supply, since the beginning of the fuel supply does not change, but occurs at the moment the plunger completely covers the sleeve holes.

Plunger pairs have a greater fit accuracy, which excludes the possibility of replacing the plunger or sleeve in this pair. In the event of a failure of the sleeve or plunger during repair, it is necessary to replace the entire plunger pair. It is also impossible to dismantle the delivery valve and its seat.

When changing the engine operating mode, the amount of fuel supplied is changed by the simultaneous rotation of all pump plungers in one direction by the same angle.

To rotate the plunger, a rotary sleeve is loosely fitted on the lower part of each sleeve, the slots of which include two protrusions of the plunger. A gear ring is put on the upper end of the bushing, which engages with the rack.

The rail moves in the desired direction with the regulator, while turning the rotary bushings and plungers. With an increase in fuel supply, the pump rail should be moved towards the drive, with a decrease in supply - towards the regulator.

The maximum stroke of the pump rack is limited by the corrector, which is a spring stop of the rack, which allows a slight additional movement of the rack in the direction of increasing the fuel supply only when the engine is overloaded, when the crankshaft speed is reduced.

Rice. 21. Fuel supply section of the pump:
1 - rotary sleeve; 2 - gear ring of the rotary sleeve; 3 - limiter for lifting the discharge valve; 4- discharge valve; 5 - discharge valve seat; 6 - sealing gasket; 7 - plunger sleeve; 8 - pump rail; 9 - plunger; 10 - installation mark plunger

To release air that has entered the power system, there are plugs on the upper plane of the pump housing.

The friction parts of the high pressure pump are lubricated by the oil circulating through the pump housing. The oil is supplied to the pump through the oil pipeline, the oil is drained through the oil pipeline.

The all-mode centrifugal speed controller of the crankshaft, mounted on the pump, maintains within certain limits the set speed of the engine crankshaft at any load and at Idling, and also limits the change in the number of revolutions within acceptable limits with a decrease and increase in load.

With frequent changes in engine load, the regulator automatically changes the fuel supply and maintains any given speed mode in the range from 500 to 1850 rpm of the engine crankshaft.

The regulator is attached to the end of the fuel pump and forms one unit with it. It consists of six spherical steel weights located in the grooves of the cross, which is mounted on the tapered shank of the camshaft. From the side of the pump, the balls rest against a fixed conical plate, planted in a recess in the regulator housing. On the opposite side, the balls rest against a movable flat plate mounted on the regulator sleeve. The flat plate can rotate freely and, together with the clutch, move along the axis along the shank of the cross when the regulator balls diverge or converge under the action of centrifugal force.

The axial movement of the flat plate is transmitted through the thrust ball bearing, lever stop and roller to the regulator lever. The lever can rotate around the axis and move the fuel pump rack. Springs hold the lever in a predetermined position.

The speed controller is lubricated with oil poured into its housing through the filler neck. At the bottom of the back cover of the regulator there is a control plug 6 for checking the oil level in the housing, even lower is a drain plug 5 of the regulator housing.

Maintenance high pressure fuel pump and speed controller are performed in the following volume.

Periodically after 100 hours of engine operation:
- check the oil level in the speed controller and add oil to the level of the control plug;
- check the advance angle of the fuel supply by the position of the mark on the drive flange and the cam disk of the pump drive clutch.

Periodically, after 500 hours of engine operation, the high-pressure fuel pump lubrication oil supply line is removed, the jets in the oil line fittings are cleaned and blown with compressed air.

Periodically, after 1000 hours of engine operation, change the oil in the speed controller with flushing the controller with hot oil.

Rice. 22. Fuel pump drive clutch: a - clutch details; b - clutch assembly;
1 - camshaft of the fuel pump; 2 - key; 3 - cam half-coupling; 4 - nut; 5 - textolite disk; 6 - cam disc; 7 - bolts; 8 - fuel pump drive shaft; 9 - leading flange; 10 - coupling bolt; II - marks on the bearing housing and cam half-coupling; 12 - mark on the leading flange; 13 - marks on the cam disk

Periodically, after 2000 hours of engine operation:
- check and adjust the beginning of the fuel supply by the pump sections along the gap between the end of the plunger and the discharge valve seat;
- check and adjust the uniformity of the fuel supply by the pump sections.

In each case of installing the pump on the engine, the fuel supply advance angle is checked using the marks on the cam half-coupling and the bearing housing and the flywheel flange.

Checking and adjustment of the high pressure fuel pump must be carried out by qualified personnel in a special workshop equipped with stands.

To check and adjust on the stand, the high-pressure pump is removed from the engine in the following sequence.

Turn the crankshaft until the marks on the bearing housing and the cam half are exactly aligned.

With this position of the crankshaft, it is further simplified to check and adjust the fuel injection advance angle after installing the pump, it is only necessary after removing the pump not to disturb the position of the crankshaft.

Disconnect the high pressure fuel lines, remove fuel filter with a bracket, disconnect the automatic fuel shut-off valve, disconnect the fuel supply lever, unscrew the pump mounting bolts. Cover the ends of the fuel lines with clean oiled paper or electrical tape to prevent contamination.

Turn the pump to the right block (when viewed from the transmission side) and, lifting it by the regulator housing, disengage it and remove it towards the engine flywheel.

On the pump removed from the engine, first of all, check the smoothness of the rail. To do this, manually simultaneously rotate the pump camshaft by the coupling half and turn the fuel supply lever, which must move smoothly without jamming. The presence of jerks when moving the lever indicates jamming of the rack.

Checking and adjusting the start of fuel supply by pump sections along the gap between the end of the plunger and the discharge valve seat is carried out in the following sequence.

Install the pusher of the section to be checked in c. m.t. and, lifting the plunger with a screwdriver, measure the gap with a feeler gauge. The gap should be within 0.5-1 mm. For sections of one pump, a difference in the gap size is allowed no more than 0.2 mm. The moment when the plunger starts supplying fuel is determined by this gap. If there is no clearance, the pump may be damaged due to the impact of the plunger on the valve seat.

If the actual values ​​of the gaps do not correspond to the required ones, adjust the gaps in such a way that the beginning of the fuel supply by sections alternates after 30 °. A deviation of no more than 0°20' from the start of fuel supply by any section of the pump relative to the first is allowed.

The gap is adjusted with a bolt, which is locked with a lock nut. To increase the gap, the adjusting bolt is turned in; to reduce the gap, it is unscrewed.

Checking and adjusting the uniformity of the fuel supply by the growth sections is carried out in the following sequence:
- fuel is supplied from the tank to the pump, fixed on the stand, and a tube is connected to the fitting of the checked section or
- a hose with an open end, and their high-pressure fuel lines are connected to the remaining fittings;
- prepare dishes for weighing fuel with a capacity of 150-200 cm3, weigh it with an accuracy of ± 1 g;
- unscrew the air release screws on the pump housing (do not tighten the screws until clean fuel without air bubbles appears during pumping);
- setting the fuel supply lever to the maximum supply position, pump the system by rotating the pump shaft for 2-3 minutes and then allow the fuel to drain from the tube;
- weighed dishes are placed under the free end of the tube of the checked section, and other clean dishes are placed under the ends of the remaining fuel lines;
- uniformly rotating the pump shaft at a speed of 50-60 rpm, make 250 full revolutions of the shaft, after which the fuel supplied by the measured section is weighed with an accuracy of ± 1 g;
they also check the fuel supply by the remaining sections of the pump and record the results:

Rice. 23. The position of the camshaft of the pump when checking the gap between the plunger end and the discharge valve seat: 1 - pusher; 2 - adjusting bolt; 3 - spring plate; 4 - plunger; 5 - locknut; 6 - cam shaft of the pump; a - checked gap

The difference between the highest and lowest feeds should not exceed 10% in relation to the smallest;
if the difference between the feeds exceeds 10%, the test is repeated and, if the result remains the same, the uniformity of the feed is adjusted. The feed is regulated by rotating the rotary sleeve, having previously released the coupling screw of its ring gear. To increase the feed, turn the rotary sleeve to the left, to decrease the feed - to the right. The regulation is continued until the necessary uniformity of fuel supply is obtained.

On the ring gear and the rotary sleeve there are marks applied at the factory after adjusting the uniformity of the fuel supply by the pump sections.

In the case of disassembling the high pressure fuel pump and adjusting it on a special stand, the following data are used: the output of the pump rack must be 11 mm; the amount of fuel given out by one section of the pump for 400 plunger strokes when the pump camshaft rotates at a speed of 675 rpm should be 52 cm3; the difference between the deliveries of the pump sections must not exceed 2 cm3.

The fuel pump is installed on the engine in the reverse order of removal. Before installation, check the tightness of the bolts of the lower stamped housing cover to prevent oil leakage.

After installing the high pressure pump on the engine, air is removed from the system and the fuel supply advance angle is checked.

Removal of air from the fuel system is carried out in all cases of violation of the tightness of the system. The air that has entered the system disrupts the normal start-up and operation of the engine, so its presence in the system is unacceptable. During the operation of the car, air is systematically removed from the engine power system through special plugs on the cover of the final fuel filter and on the high-pressure fuel pump housing by pumping fuel through the system.

To pump fuel through the system, turn the engine crankshaft with a starter while simultaneously maintaining the oil pressure in the lubrication system with an oil pressure of at least 3 kg / cm2 so that the emergency shutdown valve for the fuel supply does not shut off the fuel supply to the pump, and also to protect the crankshaft bearings from wear.

Initially, air is removed from the final filter by opening the plug and pumping the system until fuel appears without air bubbles.

Then the plug on the filter is closed and, having opened the plugs on the pump housing and setting the fuel supply lever to the maximum supply position, the system is pumped until clean fuel appears.

Checking and adjusting the fuel advance angle can be done by several methods, each of which should be used depending on the appropriateness of their use in a particular case.

Sections of the high-pressure fuel pump must supply fuel to the engine cylinders on the compression stroke for 30-32 ° (according to the angle of rotation of the crankshaft) before the piston in this cylinder approaches v. m. t.

The design of the fuel pump drive coupling allows you to change the fuel supply advance angle and set it accurately using the marks on the drive flange and on the cam disk, as well as on the cam half coupling and on the ball bearing housing.

There are ten notches on the cam disk (the division price between them is 3 ° in the angle of rotation of the disk or 6 ° in the angle of rotation of the crankshaft). The middle division has a double width, its price is respectively 6 or 12 °. Thus, when the pump shaft is rotated by one small division of the cam disk, the fuel supply advance angle will change by 6 ° of the crankshaft rotation, when turning to the middle (wide) division, the angle will change by 12 °. To increase the advance angle of the fuel supply, the cam half-coupling is rotated along the course of the pump camshaft, to decrease it, against the course of the pump shaft.

The fuel supply advance angle is precisely set at the factory, after which the angle value is indicated in the engine log, as well as the relative position of the marks on the drive flange 9 and on the cam disk of the fuel pump coupling.

During operation of the engine, fine adjustment of the angle may be impaired either as a result of loosening the bolts (in this case, the position of the marks will change), or due to wear on the slots on the drive flange (with a weak tightening of the bolt), or due to an increase in clearances in the fuel pump drive gears.

Checking and adjusting the advance angle of the fuel supply according to the marks on the drive flange and cam disk 6 of the pump drive clutch is carried out by comparing the actual position of the marks with their position indicated in the engine log.

If the actual position of the marks does not correspond to that recorded in the form, check the fastening of the drive flange with the bolts unscrewed and, if necessary, tighten the bolt, after which the cam half-coupling is rotated and the initial position of the marks is restored. Then the bolts are tightened and wired.

Checking and adjusting the fuel supply advance angle using a torque gauge is carried out in the following sequence.

A momentoscope is installed on the fitting of the second section (section count from the drive side) of the high-pressure pump, made from a segment of the high-pressure fuel line and a glass tube with an inner diameter of 2 mm, connected by a segment of a rubber tube.

Remove air from the final fuel filter and fuel pump.

Having set the fuel feed lever to the maximum feed position and maintaining the oil pressure of at least 3 kg / cm2 with an oil pump, rotate the crankshaft for five to six revolutions to fill the momentoscope with fuel.

Rotating the crankshaft along the course, combine the marks on the bearing housing and on the cam half-coupling of the pump, then turn the crankshaft against the stroke by 15-20 °.

Squeezing the gum of the momentoscope, remove part of the fuel from it so that the tube is half filled with fuel.

Slowly rotating the crankshaft along the course, determine the moment of the beginning of the movement of fuel in the momentoscope and stop the rotation of the shaft. The moment of the beginning of the movement of fuel corresponds to the beginning of the supply of fuel by the second section of the pump to the 1 liter cylinder. In this case, the coincidence of marks 11 on the bearing housing and on the cam half-coupling indicates the correct determination of the beginning of the movement of fuel in the momentoscope.

According to the graduated rim of the flywheel, the actual advance angle of the fuel supply is determined. If it does not correspond to that specified in the engine form, rotating the crankshaft along the stroke, set the piston 1l of the cylinder on the compression stroke to the position corresponding to the fuel supply advance angle indicated in the form. The onset of the compression stroke in the cylinder can be determined by unscrewing the air valve and covering the hole in the cylinder head with a finger, by the gas pressure on the finger (on the compression stroke, the pressure is much stronger than on the exhaust stroke). After loosening the bolts, turn the cam half-coupling against the stroke by 15-20 ° and then slowly turn it along the stroke until the fuel begins to move in the momentoscope. In this position, tighten the bolts.

Rotating the crankshaft along the way, check the set angle and, with satisfactory results, lock the bolts with wire. If the location of the marks has changed, which may occur due to an increase in the gaps in the fuel pump drive gears, the new position of the marks is recorded in the engine log.

Checking and adjusting the fuel supply advance angle according to the marks on the cam half-coupling and the bearing housing is performed in the following sequence.

Rotating the crankshaft along the course, set the piston 1l of the cylinder to position c. m.t. on the compression stroke.

Turn the crankshaft against the stroke by 50-60 °.

Slowly rotating the crankshaft, align the marks on the cam half-coupling and the bearing housing. The coincidence of the marks corresponds to the moment when the second section of the pump starts supplying fuel to the 1 liter cylinder.

The graduated rim of the flywheel determines the angle corresponding to this position of the pump. If the actual angle does not correspond to that specified in the engine form, set the piston 1l of the cylinder to the position corresponding to the advance angle of the fuel supply indicated in the form. After loosening the bolts and turning the cam clutch, align the marks and tighten the bolts.

The set advance angle of the fuel supply is checked and, if the results are satisfactory, the bolts are locked with wire.

Closed-type nozzles are designed to inject fuel into the combustion chamber in atomized form. The fuel is supplied to the nozzle through the side opening and through the vertical opening in the housing enters the slotted filter, where it is cleaned from the smallest mechanical particles.

The slotted filter consists of two steel bushings that fit one into the other. The bushings are made with high precision, the gap between them is selected in the range of 0.02-0.04 mm, and replacement of the filter bushings individually is not allowed. The outer sleeve is smooth, the inner sleeve on the outer surface has longitudinal grooves, alternately extending either to its lower or to its upper end.

After passing the filter, the fuel enters the annular groove at the end of the atomizer body and then through the vertical hole in the atomizer body it enters under the large cone of the needle.

When the fuel pressure rises to a value of 210 kg/cm2, under the influence of this pressure the needle rises, compressing the spring, and the fuel is injected into the combustion chamber through seven holes (each 0.25 mm in diameter) of the atomizer. When the fuel pressure decreases, under the action of the spring, the needle sits in the atomizer, abruptly stopping the injection.

The leaked part of the fuel through the gap between the needle and the atomizer enters the cavity where the nozzle spring is located, and then through the hole it enters the fitting of the fuel supply pipe. A special tube running along the cylinder head cover collects this fuel and discharges it into a container. The fuel accumulating in the tank should be drained through the plug and, after filtering, poured into the tank.

The needle and atomizer are a precision pair; during the manufacturing process, they are lapped and brought together, and individual replacement of the parts of this pair is not allowed.

The fuel injection pressure of the injector is adjusted by tightening the spring with a bolt locked with a lock nut.

Periodically, after 500 hours of engine operation, as well as in the event of difficult starting, increased smoke and a decrease in engine power, the nozzles are checked and adjusted.

To check the injectors are removed from the engine either through the hatches in the cylinder head covers using a special tool, or with the cylinder head covers removed using a screwdriver. In both cases, the high-pressure fuel lines are first removed and the nozzle fastening nuts are unscrewed.

If the nozzle is replaced, a new sealing ring is installed. Violation of this rule may result in the piston hitting the injector atomizer.

The injectors are checked for needle lift pressure, atomization quality and no fuel leakage.

The injectors are checked on a special stand or on a simple device consisting of a high-pressure fuel pump section and a reference injector. The tested (Fig. 30) and reference nozzles are fixed in a vertical position and connected with a tee.

Turning on the maximum fuel supply by the pump and evenly rotating the pump shaft, it is necessary to make several injections of fuel through the nozzles. If the needle lift pressure of the injector being tested is set correctly, fuel injection from both injectors will be simultaneous.

The absence or delay of injection from the reference injector indicates a weak tightening of the spring of the tested injector.

The absence or delay of injection from the injector being checked indicates that the spring is too tight or the atomizer needle of the injector being checked is stuck.

Rice. 25. Nozzle:
1 - sprayer body; 2 - sealing ring; 3 - spray needle; 4 - union nut; 5 - outer sleeve of the slotted filter; in - the internal plug of the slit filter; 7 - rod; 8 - nozzle body; 9 - plate; 10 - spring; 11 - support washer; 12 - locknut; 13 - adjusting bolt

Rice. 26. Fixing the injector to be tested and the reference injector with a tee

In both cases, by loosening the locknut and turning the adjusting bolt, simultaneous injection is achieved from the reference and test nozzles. If this fails, disassemble the nozzle and check the movement of the needle in the sprayer.

The quality of fuel atomization is checked by pumping fuel through the nozzle and observing the jets coming out of the atomizer.

The quality of atomization is considered normal if the fuel comes out uniformly from all nozzle openings in a fine, misty state and there is no drop formation at the end of the atomizer before and after injection.

Clogging, nozzle holes are checked by injecting fuel onto a sheet of paper.

According to the trace left on the paper, the number of non-working holes is determined, which, after disassembling the nozzles, are cleaned with a steel wire with a diameter of 0.2 mm.

Leakage of fuel from the atomizer is checked by slowly supplying fuel to the nozzle, raising the fuel pressure until the needle opens, but not allowing injection. If there is leakage, a large drop of fuel will form at the end of the atomizer.

Injectors that have poor atomization, clogged holes or fuel leakage are disassembled to eliminate defects.

The nozzle is disassembled in the following sequence.

Having unscrewed the atomizer nut, the slotted filter bushings are removed and the atomizer body is knocked out with light blows of a copper hammer. Without pulling out the needles, put the atomizer in a bath of diesel fuel. Having unscrewed the lock nut, unscrew the adjusting bolt, remove the washer, spring and rod. Carefully remove the needle from the nebulizer.

If the needle is stuck, clamp it by the shank in a vise and pull the sprayer body towards you.

If the needle cannot be removed by this method, the atomizer with the needle is boiled for 2-3 hours in a solution containing 10 g of chromic and 45 g of caustic soda per 1 liter of water.

After removing the needle, the atomizer is washed, and then the needle is rubbed against the atomizer with periodic washing with diesel fuel. A normally lapped needle, extended from the atomizer body by 1/3 of its length, must, under the action of its own weight, without delay, completely descend into the atomizer body inclined at an angle of 45 °. If the tightness of the needle-atomizer pair is not ensured by lapping, i.e., when the nozzle is rechecked, fuel leakage will be observed, the precision pair is replaced.

Rice. 27. Fuel control drive:
a - view from the left side of the car; b - view from the right side of the car; 1 - manual control handle; 2 - thrust; 3 – withdrawal spring; 4, 5, 9, 10 and 12 - levers; 6 - pedal; 7 and 11 - thrust; 8 - adjusting bolt; 13 - screw of the minimum speed of the crankshaft of the engine; 14 - screw limiting the maximum speed of the crankshaft of the engine

To clean the parts of the nozzle from soot, wooden blocks are used and in no case should sandpaper be used for this purpose. Before assembly, the parts of the atomizer are washed first in clean gasoline and then in diesel fuel. The assembled nozzle is adjusted to the needle lift pressure and checked for atomization quality.

The fuel control drive provides both a complete shutdown of the fuel supply and its maximum supply.

The fuel supply control drive has an adjustment for limiting the stroke of the right rear roller lever and an adjustment for the position of the pedal.

The limit of the lever travel is adjusted by a bolt with the rod disconnected. To adjust, unscrew the bolt, move the right lever forward to the stop and bring the bolt until it comes into contact with this lever. Release the lever and screw in the bolt 1/6 of a turn, which corresponds to a gap of 0.25 mm between the regulator lever and the maximum speed limit screw. This position of the bolt is fixed with a lock nut.

After adjusting the lever stroke limit, adjust the position of the pedal. To do this, the lever is placed in a vertical position and the rod is connected, adjusting its length so that the finger holes in the fork and lever coincide. After setting the required length of the rod and attaching it to the lever, tighten the fork locknut.

The final control of the maximum and minimum number of revolutions of the crankshaft is carried out according to the technical form for the engine.

In case of discrepancy between the actual maximum number of revolutions indicated in the technical form, it is necessary to re-adjust the fuel supply drive.

Engine air supply system

The engine air supply system consists of air filter, inlet piping, a whine removal ejector and an emergency engine stop device.

The VTI-4 air filter is a combined type, two-stage, mounted on the fuel tank bracket.

The filter is connected to the engine intake pipes by two cast aluminum pipes and hoses. The filter consists of a housing containing an inertial dry air cleaning apparatus and a dust collector (first stage of cleaning), and three rectangular cassettes filled with thin steel wire - gimp soaked in oil (second stage of cleaning). The inertial device consists of 54 cyclones built in parallel into the filter housing.

The principle of operation of the air filter is as follows: under the action of vacuum in the engine cylinders on the intake stroke, air enters through the nozzles located tangentially to the cyclones in their upper part, goes around the cylindrical nozzles of the air collection chamber inside the cyclones and, thanks to this design of the intake, rushes in the cyclone in a spiral down.

Rice. 28. VTI-4 air filter and dust removal ejector:
1 - cover; 2, 4, 6 and 9 - sealing gaskets; 3, 5 and 7 - cassettes; 8 - air intake pipes; 10 - nozzles; 11 - cyclones; 12 - dust collection bin; 13 - dust suction pipe; 14 - ejector pipe; 15 - right exhaust pipe of the engine; 16 - pipe outlet of purified air

At the same time, centrifugal force acts on all dust particles in the air, which tends to throw them to the cyclone wall. Large dust particles develop such a significant centrifugal force that they break away from the air flow and, having reached the cyclone wall, descend along the cone into the bunker. Going from top to bottom (the air reaches the outlet of the nozzle of the air collection chamber, here the air flow sharply changes the direction of movement (by 180 °) and rises along the nozzle from the bottom up. Due to a sharp change in the direction of air movement, small dust particles are separated from the air and discharged into the bunker. After passing through the nozzle into the air collection chamber, air with a small content of the smallest dust fractions enters for further “wet” cleaning into the second stage of the filter cassette, and then through the nozzles into the engine inlet pipeline.

The dust removal ejector from the air filter hopper operates automatically continuously throughout the entire operation of the engine.

The ejection device is made on the right (along the vehicle) exhaust pipe, where the dust suction pipe of the filter hopper is connected, ending with a diffuser directly in front of the narrowest section of the ejector. The exhaust gases, passing through the ejector at high speed, create a vacuum in the dust suction pipe, as a result of which the dust is sucked out of the hopper and carried away by the exhaust gases to the outside.

The VTI-4 air filter is also installed on a BelAZ-531 single-axle tractor. The dust removal ejector from the air filter hopper on this vehicle has a different design, but the principle of its operation is the same: the dust is removed by the exhaust gases of the engine.

The engine emergency stop device consists of two dampers installed in the pipes for removing clean air from the air filter, and a damper control cable led to the driver's cab.

With the help of dampers, the driver shuts off the air supply to the cylinders if the engine goes "peddling".

Maintenance of the engine air supply system consists of periodic cleaning and flushing of the cassettes and the air filter housing, as well as parts of the dust removal ejector.

Periodically, after 100 hours of engine operation, without removing the air filter housing from the car, the cassettes are cleaned in the following sequence.

After removing the filter cover, the cassettes are removed and each cassette is thoroughly washed in diesel fuel or kerosene.

For better rinsing periodically turn the cassettes over and change the contaminated liquid. Washed cassettes are blown with dry compressed air to remove the washing liquid from the packing or, if compressed air is not available, allow the liquid to drain. The upper and middle cassettes are impregnated in engine oil by immersing them in a bath of oil heated to a temperature of + 60-70 ° C, after which the oil is allowed to drain. Do not soak the lower cassette with oil. Wipe the inner surface of the housing and filter cover with a rag to remove dust deposits. Prepared cassettes are placed in the filter housing on gaskets in such a way that the gap between the housing wall and the cassettes is approximately equal around the entire perimeter. Install the gasket and close the filter with a lid. Before installation, all filter seals are lubricated with grease (solid oil or technical petroleum jelly).

Periodically, after 500 n of engine operation, the air filter housing and parts of the ejection device are cleaned in the following sequence.

Remove the air filter and ejector from the car. In addition to the maintenance of the air filter cassettes, as indicated above, the filter housing and parts of the ejection device are cleaned by washing the filter in a bath with diesel fuel. After flushing, all channels are blown with compressed air and the parts are dried.

When installing the filter on a car, attention should be paid to the tightness of the air duct connections in order to prevent the ingress of uncleaned air into the engine cylinders.

When the vehicle is operating in very dusty conditions, maintenance of the engine air supply system is performed at a shorter frequency than indicated, specifically based on the experience of operating the vehicle in these conditions.

Failure to properly maintain the air filter and ejector will ignite carbon deposits in the ejector and oil on the filter cartridges, resulting in engine damage.

To avoid this in a timely and complete manner. volume, carry out maintenance of the engine air supply system, and do not turn off the vehicle platform heating system. The ejector works effectively only with high resistance in the engine exhaust pipeline, i.e. when the platform heating is on. With platform heating off or exhaust plugs removed. platform openings, the exhaust gas flow rate in the ejector drops sharply and hot gases can be sucked through the dust suction pipe to the air filter.

It is possible to install contact-oil type air filters on BelAZ-540 vehicles, which are installed on vehicles with YaMZ engines. Maintenance of these air filters is carried out in accordance with the recommendations given in the section "YaMZ-240, YaMZ-240N Engines".

Engine lubrication system

The engine lubrication system is combined with a "dry" sump. Under pressure, the main and connecting rod bearings of the crankshaft, bearings of the gear mechanism and camshafts, cams and valve plates are lubricated. Cylinder mirrors, gears of the gear mechanism, valve bushings are lubricated by spraying.

Rice. 29. Engine lubrication system:
1 - oil pipelines for supplying oil to the cylinder heads; 2, - oil pump; 3 - bypass valve; 4 - oil pump; 5 - check valve; 6 - oil temperature gauge; 7 - oil filter; 8 - oil dispenser; 9 - oil tank; 10 - oil heating coils; 11 - oil drain plug; 12 - defoamer; 13 - oil measuring rod; 14 - oil pressure equalization line in the oil tank; 15 - oil cooler; 16 - valve for shutting off the oil cooler; 17 - valve bypass valve; 18 - compressor; 19 - oil pipeline for supplying oil to the oil filter; 20 - oil pipeline for removing oil after shelving (main line); 21 - oil pipeline for supplying oil to the emergency shutdown valve for fuel supply; 22 - oil pipeline for supplying oil to the high pressure pump; 23 - oil pipeline for draining oil from the high pressure pump housing; 24 - pressure gauge sensor.

Crane position:
a - the oil cooler is on; b - oil cooler off

The engine lubrication system includes an oil tank, an oil pump, an oil cooler, an oil cooler cut-off edge, an oil pump, an oil filter, a crankcase and engine oil channels, and connecting oil lines.

The oil level in the lubrication system is controlled using an oil measuring rod installed in the oil tank.

The oil pressure in the system is controlled by a pressure gauge, the sensor of which is installed on the oil pipeline.

The oil temperature is controlled by a temperature gauge installed on the oil outlet pipe from the engine.

The lubrication system of the compressor and high pressure fuel pump is connected in parallel to the engine oil line.

The oil tank is welded, designed to collect oil pumped out of the engine crankcase, equipped with an oil filler neck, closed with a sealed plug. The tank is located in the front part under the right wing of the car, which has a special hatch with a cover for access to the oil filler neck.

Inside the tank there is a defoamer through which the oil coming from the engine passes, as well as coils designed to heat the oil before starting the engine. If a starting engine heater is installed on the car, the coils are connected to it and the liquid circulating through them heats up the oil in the tank. In the absence of a starting heater on the vehicle, the coils can also be used to heat the oil by passing hot water from special installation or by connecting them to a steam heating system.

To equalize the pressure inside the tank when the oil level changes in it, the upper part of the tank is connected by an oil pipeline to the crankcase space of the engine.

Rice. 30. Oil pump:
1 - bushing; 2 - drive roller; 3 - pressure reducing valve; 4 - spring; 5 - adjusting bolt; 6 - locknut; 7 - Housing cover; 8 - body of the injection section; 9 - housing of the lower pumping section; 10 - driven gear of the upper pumping section; 11 - oil intake grid by the upper section; 12 - pump drive gear; 13 - drive gear of the upper pumping section

Oil pump - gear type, three-section, designed to supply oil under pressure to the system, as well as to pump oil from the engine crankcase to the tank.

Two sections of the pump (upper) - pumping out, one (lower) - forcing. The upper section of the pump pumps oil from the front of the crankcase, the middle section - from the rear of the crankcase through the oil receiver.

Constant pressure in the engine oil line is maintained by a pressure reducing valve installed on the discharge section and adjusted to a pressure of 7.5 kg/cm2. After adjustment at the factory, the pressure reducing valve is sealed. It is forbidden to violate the valve adjustment.

If necessary, the valve is unscrewed together with its body without breaking the seals.

The oil cooler is designed to cool the oil pumped out of the engine crankcase on its way to the tank. It consists of a tubular-lamellar core and two tanks. The oil from the pump enters the upper tank, makes a looping movement along the core and from the lower tank through the oil pipeline through the radiator shut-off valve is drained into the tank.

The oil cooler shut-off valve is designed to turn off the radiator in winter time.

When the radiator is on (handle in position a), the oil from the engine enters the radiator for cooling and then drains into the oil tank. When the radiator is off (the handle is in position b), the oil from the engine is drained directly into the tank.

A bypass valve is installed in the valve body, adjusted to a pressure of 1.2 kg / cm2.

The valve protects the radiator from damage in the event of a significant increase in pressure in the oil line of the radiator. The pressure may rise, for example, when starting the engine with cold oil.

Oil pump - gear type, with electric drive, is attached to the lower half of the engine crankcase on the right side of the vehicle. It is designed to supply oil to the main engine line before starting in order to prevent dry friction of the bearings at the time of starting. The oil pump is controlled remotely from the cab.

Rice. 31. Oil cooler shut-off valve:
1 - body; 2 - valve shutter; 3 - handle; 4 - spring; 5 - bypass valve.

The position of the crane handle: a - the channel to the oil cooler is closed; b - the channel to the oil cooler is open

The need to pump oil into the engine line before each start is caused by the fact that after the engine is stopped, hot and low-viscosity oil flows off the working surfaces of the bearings, and the remaining oil is not enough to form an oil film at the first revolutions of the engine shaft. In addition, immediately after start-up, the oil pump does not have time to supply the required amount of oil to the line, since cold oil is bypassed in large quantities through the pump pressure reducing valve.

Before starting the engine, it is imperative to create a pressure of 3-4 kg / cm2 in the lubrication system with an oil pump.

The oil pump is equipped with a bypass valve that protects the pump from damage in the event of a significant increase in pressure in the delivery line. In addition, a check valve is installed in the delivery line of the oil pump, which allows oil to enter the engine line when the oil pump is operating and prevents oil from leaking from the line when the engine oil pump is operating.

The oil filter consists of a housing with a cover, two slotted oil cleaning sections and a bypass valve.

The filtering sections of the slotted oil cleaning are steel cylinders with longitudinal corrugations, on which a brass profiled tape is tightly wound. The oil is cleaned by passing into the gaps between the turns of the tape. The filter sections work in parallel in the filter.

The bypass ball valve installed in the filter housing, adjusted to a pressure of 1.5 kg/cm2, ensures the supply of crude oil to the rubbing parts of the engine in case of severe contamination of the filter sections or starting the engine with increased oil viscosity.

Rice. 32. Oil filter:
1 - coupling bolt; 2 - cover; 3 - rubber sealing ring; 4 - body; 5 - slot cleaning sections; 6 - tubular rod; 7 - bypass valve; 8 - oil outlet fitting to the engine emergency shutdown valve; 9 - oil outlet fitting to the main engine oil line

Maintenance of the engine lubrication system includes monitoring the technical condition of the engine and the quality of the oil sludge in the tank, flushing the oil filter, changing the engine oil.

Every day before starting the engine, the oil sludge is drained from the oil tank and checked for the absence of coolant and metal particles. The presence of coolant or metal particles in the oil indicates a malfunction of the engine.

Periodically, after 100 hours of engine operation, the engine oil filter should be washed in the following sequence.

Loosen the pinch bolt, remove the cover and drain the oil from the filter. Remove both filter sections from the housing, inspect them and clean them thoroughly. The sections are cleaned by washing them in a bath with diesel fuel, periodically cleaning the outside with a hair brush and blowing compressed air through the internal cavities, i.e. with an air flow opposite to the oil flow. Poor flushing of the slotted sections leads to an increase in the resistance of the filter, while the bypass valve is activated, causing the pressure in the main oil line to drop sharply and unfiltered oil enters the rubbing engine parts, increasing the wear of the parts. Install the washed slotted sections into the filter by turning them around the rod.

Install the filter cover, checking the presence of the O-ring, and tighten the pinch bolt.

Create a pressure of at least 3 kg / cm2 in the lubrication system with an oil pump and turn the crankshaft several revolutions with the starter without supplying fuel. After starting the engine, check the oil filter for leaks.

Change engine oil periodically. The first two oil changes on a new engine should be performed after 100 hours of engine operation, subsequent oil changes when the engine is operated on recommended oils with fuel additives should be performed after 500 hours of engine operation.

Change the oil in the following sequence. Having unscrewed the drain plugs, drain the oil from the tank and crankcase immediately after the engine stops; Rinse the oil filter, tighten the drain plugs and pour 30 liters of fresh oil into the tank, heated to a temperature of +80-90 °C. Bleed the system, start the engine and let it run (with the oil cooler on) for 5 minutes at 500-600 rpm to flush the system. Drain flushing oil and fill the system with fresh oil up to the upper mark of the oil dipstick in the tank. After starting the engine, check for leaks oil system, oil leakage is not allowed. It is recommended to periodically remove the oil lines after 500 hours of operation for thorough flushing and cleaning.

Engine cooling system

Engine cooling system - liquid, closed, with forced circulation of liquid from the pump. The circulating liquid cools the engine blocks and cylinder heads, the engine exhaust pipes with cavities for the passage of liquid, the compressor cylinder block and head.

In the engine cooling system, parallel to the water radiator of the engine, a cabin heater radiator is included, which takes part of the heat to heat the cabin. The cabin heater radiator is switched on using a special tap 6.

Depending on the degree of heating of the liquid, its movement in the system is carried out either in a small circle of circulation (the radiator is turned off), or along big circle circulation (through the radiator).

Rice. 33. Engine cooling system:
1 - water radiator; 2 - compressor; 3 - plug: 4 - thermostat box; -5 - seasonal damper; 6 - valve for turning off the cab heater radiator; 7 - cabin heater radiator; 8 - steam pipes; 9 - expansion tank; 10 - plug with a steam-air valve; 11 - coolant temperature gauges; 12 - cooled exhaust pipes of the engine; 13 - engine cooling jacket; 14 - oil heating coils; 15 - taps for draining the cooled liquid; 16 - starting heater; 17 - engine water pump

The direction of fluid flow is controlled by thermostats.

To prevent the formation of vapor-air plugs in the system, which can impede the movement of fluid, impair heat transfer and thereby reduce the efficiency of engine cooling, there is a system of vapor pipes connecting the upper part of the cylinder head cooling jacket and thermostat box with the upper part of the expansion tank, into which water vapor is removed and air in the system.

The temperature of the liquid in the system is controlled by means of two temperature gauges, the sensors of which are installed on the liquid discharge pipelines from the right and left blocks.

The water pump is centrifugal type. The pump impeller, made of stainless steel, rotates on two ball bearings, which are lubricated by oil coming from the engine crankcase.

To prevent leakage of water and oil, mechanical seals are installed on the impeller shaft, each of which consists of a textolite washer, a rubber ring and a spring. Textolite washers rotate together with the impeller shaft and seal the joints with the help of springs.

Inspection holes are drilled between the seals in the intermediate insert and in the pump housing, the leakage of water or oil from which indicates a malfunction of one or another seal.

Developed by the factory and installed on individual engines new design The water pump shaft seal differs from that described above by the presence of a rubber cuff sealing the oil cavity and a corrugated stuffing box sealing the water cavity. This seal has increased wear resistance and provides better sealing of the impeller shaft.

The thermostat box is used to automatically control the temperature of the coolant in the engine cooling system and accelerate its warm-up after starting.

When the coolant temperature is below +70 °C, the thermostats block the access of the coolant to the water radiator. The circulation of the liquid occurs in a small circle, which accelerates its heating. When the temperature of the coolant rises above +70 °C, a water radiator is automatically connected to the system and a further increase in the temperature of the liquid stops.

Rice. 34. Water pump: a - old seal design; b - new seal design;
1 - leading fist; 2 - drive washer; 3 - oil seal spring; 4 - textolite washer; 5 - rubber ring; 6 - spring; 7 - impeller with shaft; 8 - gasket; 9 - drain cock; 10 - body; I - bushing; 12 - retaining ring; 13 - shock absorber: 14 - seal washer; 15 - spring; 16 - corrugated gland; 17 - rubber cuff

The seasonal damper installed in the thermostat box opposite the coolant filling hole must be open in winter. When the damper is open, about one third of the coolant flow from the engine to the radiator enters with a small circle of circulation. This prevents the radiator from freezing when the coolant circulates in a small circle (in the case of using water as a coolant).

The expansion tank is designed to compensate for fluid losses in the cooling system, collect steam and condense it. It is installed to the right of the cab under the hood and is equipped with a neck for filling the cooling system with liquid.

The neck of the tank is closed with a stopper, in which a steam-air valve is installed, which protects the cooling system from destruction as a result of excess steam pressure or vacuum.

The steam-air valve maintains a pressure in the system slightly above atmospheric, which increases the boiling point of the liquid and reduces its losses from evaporation. With a sharp drop in pressure in the cooling system, the valve allows air to enter the system.

The water radiator is a tubular type, six-row, with solid-drawn flat-oval tubes, installed on the left side (in the direction of the car) in front of the engine.

The water cooler is mounted in one block with oil coolers of the engine and hydromechanical transmission. The radiators are mounted on a common beam on three rubber shock absorbers. On the left side (in the direction of the car) the radiator unit is attached to the cab bracket by a rod, and on the right side - to the wing strut.

There are tanks in the upper and lower parts of the radiator core. The upper tank is connected to the thermostat box with a pipe and hose, and the lower tank is connected to the engine water pump.

Radiator tanks - aluminum, have two partitions. The presence of such partitions allows you to create a loop (in three passes) circulation of the cooled liquid in the core of the radiator. The liquid flows through the tubes of the radiator core and is cooled by the air flow coming from the fan. The air blown by the fan through the radiator takes heat from the tubes and the plates soldered to them and dissipates it into the environment.

Radiator shutters are used to control the air circulation through the core of the radiators. They are installed in front of the radiators. The shutters are controlled from the driver's cab by two handles: one for engine oil and water cooler shutters, and the other for hydromechanical transmission oil cooler shutters.

Rice. 35. Fan drive:
1 - water radiator fan; 2 - fan pulley; 3 - water radiator; 4 - locknut; 5 - adjusting nut; 6 - spring; 7 - thrust; 8 - two-arm lever; 9 - tension roller; 10 - fan drive belts; 11 - engine oil cooler; 12 - oil cooler of hydromechanical transmission; 13 - fan of oil coolers of the engine and hydromechanical transmission; 14 - fan drive pulley

A drain valve for removing liquid from the cooling system is located on the water pump.

On an engine equipped with a starting heater, in addition to the above, there are also the following additional valves: on the boiler of the starting heater; on the bottom of the engine oil tank (two taps for draining fluid from the oil heating coils),

The fans have seven steel blades riveted to the hub. Both fans are located in one row in front of the heatsink block.

The left fan cools the water radiator of the engine, the right fan cools the oil coolers of the engine and hydromechanical transmission.

The fans are driven by a V-belt transmission from the engine crankshaft. Each fan is driven by two V-belts.

The drive pulley is driven by the engine crankshaft using rollers. The pulley is mounted on the cone of the driven roller, fixed with a key and secured with a nut with a lock washer. The bearing is lubricated through the gap between the driven roller and the sleeve with oil coming from the engine oil line.

The fan shafts are installed in bearing assemblies fixed on special brackets. On one side, a fan is mounted on the shaft, on the other, a driven fan pulley.

Stretching device drive belts consists of a tension roller, traction, spring and two-arm lever. The lever is connected at one end to the axis of the tension roller, and at the other - to the rod, at the end of which there is a spring.

The fan belt tension is adjusted with a nut with the lock nut released.

A normally tensioned belt, when pressing by hand on the middle of the branch between the driving and driven pulleys (branch without tension roller) with a force of 4 kg, should have a deflection of 8-14 mm.

It is especially necessary to carefully control the tension of the belts during the initial period of their operation, since at this time they have the maximum stretch, and hence the change in size.

Maintenance of the engine cooling system includes monitoring the fluid level in the system, lubricating the fan drive bearings, checking the tension of the fan drive belts, and flushing the cooling system.

Rice. 36. Fan drive pulley drive:
1 - drive roller; 2 - body of the front engine mount; 3 - beam of the front engine mount; 4 - bearing cover; 5 - stuffing box; 6 - driven roller; 7 - driving pulley of fans; 8 - lock washer; 9 - nut

The level of coolant in the cooling system should be constantly monitored and maintained within the required limits. Do not allow even short-term operation of the engine without coolant, as this leads to damage to the rubber sealing parts of the engine cooling jacket.

Periodically, after 100 hours of engine operation, it is necessary to perform the following work: check the tightness of the threaded fasteners for fastening radiators and fans, the tension of the fan and compressor drive belts; lubricate the bearings of the fan shafts and tension rollers.

Periodically, after 1000 hours of engine operation, if a noticeable increase in the temperature of the outgoing oil and coolant is observed, it is necessary to flush the cooling system to remove scale with a solution containing 1 kg of soda ash and 0.5 l of kerosene per 10 l of water, in the following sequence.

Fill the systems with the prepared solution, start the engine and let it run for 20-25 minutes at 800-1000 rpm. Stop the engine and leave the solution in the system for 10-12 hours. Start the engine again for -20-25 minutes, then stop it and drain the solution from the system. Rinse system with mild clean water by running the engine for a few minutes. Fill the system with emulsion (see "Consumables") for further engine operation.

Do not use solutions containing caustic soda to flush the cooling system.

Engine preheating system

To ensure the start of the Engine at low temperatures, a starting heater PZhD-600 is installed on cars.

Rice. 37. Installation of the fan shaft:
1 - fan pulley; 2 - bearings; 3 - body; 4 - cover; 5 - felt gland; 6 - fan shaft; 7 - grease fitting

Rice. 38. Tension roller:
1 - two-arm lever; 2 - axis of the two-arm lever; 3 - tension roller; 4 - grease fitting; 5 - cover; 6 - bearings; 7 - felt gland; 8 - roller axis

Rice. 39. Heater:
1 - gear fuel pump; 2 - electric motor; 3 - fan; 4 - circulation pump; 5 - inlet pipeline of the circulation pump; 6 - hot liquid outlet pipeline; 7 - combustion chamber; 8 - outer shirt; 9 - inner shirt; 10 - gas pipeline; 11 - pipeline for supplying liquid to the boiler; 12 - drain cock; 13 - exhaust pipeline; 14 - outer cylinder of the combustion chamber; 15 - glow plug; 16 - swirler; 17 - nozzle; 18 - solenoid valve; 19 - fuel tube; 20 - inner cylinder of the combustion chamber

The heater runs on diesel fuel and is connected to the engine power supply system.

The heat released during the combustion of fuel in the heater boiler is taken by the coolant, which is driven by a special circulation pump of the heater first through the oil heating coils 14 in the engine oil tank, and then through the engine cooling jacket and then back to the heater through a small circulation circle.

Heater device. The heater consists of a cylindrical boiler and auxiliary units mounted on it: a burner, a pumping unit, a nozzle, solenoid valve, glow plugs. The heater control panel is installed in the driver's cab.

The heater boiler is made of stainless steel and consists of four cylinders forming a combustion chamber, a gas pipeline and a jacket for the heated liquid.

The liquid enters the boiler through the pipeline under pressure from the circulation pump, passes through the entire jacket of the boiler and is discharged from the boiler through the pipeline.

The heater burner consists of an outer cylinder and an inner one. A primary air swirler is installed between the burner cover and the inner cylinder.

Through holes in the inner cylinder, secondary air is supplied to the combustion chamber.

The heater pump unit is driven by an electric motor and consists of a fan, a circulation pump and a gear fuel pump.

Heater nozzle - centrifugal type, with stacked lamellar filter. In case of clogging, the nozzle must be removed, disassembled, cleaned and checked for atomization by turning on the heater and not inserting the nozzle into the burner. The nozzle must produce a misty cone of fuel with a spray angle of at least 60°.

The solenoid valve stops the fuel supply to the nozzle when the heater is turned off.

When the heater is started, the fuel-air mixture is ignited by the glow plug. Then the candle is switched off and combustion is maintained automatically. Fuel is supplied by a pump through an open solenoid valve to the injector and from the injector at a pressure of 6-7 kg/cm2 enters the combustion chamber.

When operating the heater, the following requirements must be observed.

Fill the cooling system with a low-freezing liquid (antifreeze). In exceptional cases, at an ambient temperature of at least -30 °C, it is allowed to fill the cooling system with hot water.

It is forbidden to start the heater without coolant in the boiler, as well as topping up an overheated boiler in order to avoid damage to it.

It is forbidden to start the heater immediately after stopping or restart if the first attempt to start is unsuccessful without preliminary purging of the combustion chamber for 3-5 minutes.

When the heater is in operation, the driver must not leave the vehicle in order, if necessary, to eliminate any malfunction or eliminate the source of fire in a timely manner.

Simultaneous operation of the engine and the heater^ must not be allowed to avoid damage to the heater.

The heater is started in the following sequence:
- set the solenoid valve switch on the control panel to the Purge position and turn on the electric motor for 10-15 seconds with the switch, setting it to the Work position;
- turn on the glow plug for 30-40 seconds by moving the switch lever to the left. At the same time, the control spiral on the panel should glow to a bright red color;
- move the solenoid valve switch from the Purge position to the Operation position and the electric motor operation mode switch to the Start position if the ambient air temperature is below -20 °C.

Rice. 40. Nozzle:
1 - body; 2 - camera; 3 - gasket; 4 - screw; 5 - cover rod; 6 - end plate; 7 - fitting; 8 - filter plate; 9 - filter cover

With more high temperatures it is possible to move switch 3 directly to the Run position, bypassing the start position.

If the buzzing of the flame is heard in the heater boiler, release the switch 5 of the candle and turn the switch to the Work position (at temperatures below -20 ° C).

If there is no characteristic roar of the flame in the heater boiler, switch switch 3 to the neutral position, switch 2 of the solenoid valve to the Purge position and repeat the start-up process.

If the heater failed to start within three minutes, check the fuel supply to the combustion chamber and the glow of the spark plug.

The start-up of the heater is considered normal if, with a uniform rumble of flame in the boiler, after 3-5 minutes the pipeline that drains the liquid from the heater is hot, and the outer casing of the boiler is cold.

Strong heating of the outer casing of the boiler and the occurrence of shocks of boiling liquid in the boiler indicate the absence of liquid circulation. In this case, it is necessary to turn off the heater and find out the cause of the malfunction.

The operation of the heater is accompanied by a uniform hum of the flame in the boiler and the exit of exhaust gases of a bluish glow from the heater. Periodic take-off of flames up to 100 mm long is allowed.

After heating the coolant in the engine to a temperature of + 40 ° C, periodically, but not more than 20 seconds, turn on the engine oil pump to mix and evenly heat the oil.

Rice. 41. Electrical diagram of the heater:
1 - fuse PR2B; 2 - protection unit B320 with a fusible link 2a; 3 - switch; 4 - switch; 5 - control spiral; 6 - connecting panel; 7 - glow plug; S - solenoid valve; 9 - supercharger; 10 - electric motor; 11 - resistance panel; 12 - switch PPN -45 electric motor

The fuel supply in the heater is regulated by the screw of the fuel pump reducing valve (as the gears wear out) on the operating heater.

Turn off the heater to stop operation in the following sequence:
- set the solenoid valve switch to the Purge position to cut off the fuel supply to the combustion chamber;
- let the electric motor run for 1-2 minutes to purge the combustion chamber, then turn it off by moving switch 3 to the neutral position.

The combustion chamber and gas pipeline are purged to exclude a possible explosion of gases during the subsequent start-up of the heater.

Periodically, after 100-150 heater starts, glow plugs, nozzles and heater burners are cleaned of carbon deposits.

Compressed air engine start system

As a backup means of starting (in case of impossibility of starting with an electric starter), equipment for starting the engine with compressed air is mounted on the engine.

The air start system can be powered from a mobile compressor station or compressed air cylinders transported on a specially equipped vehicle.

The air pressure for supplying the starting system must not exceed 150 kg/cm2. The minimum air pressure at which the engine can be started is 30 kg/cm2. An air cylinder with a capacity of 20 liters filled with compressed air at a pressure of 150 kg/cm2 is sufficient for 6-10 engine starts.

The starting equipment installed on the engine consists of an air distributor, starting valves and air lines.

Compressed air from the cylinder through the valve enters the air distributor, which directs it to the starting valves of the cylinders in accordance with the order of operation of the cylinders. Under the influence of air, the valves open, and the air, moving the pistons, rotates the crankshaft of the engine.

The air distributor is attached to the high pressure fuel pump drive housing towards the front of the engine and receives rotation from the fuel pump drive gear.

Along the perimeter of the outer end of the air distributor body, there are 12 fittings with tubes through which compressed air enters the starting valves of the cylinders (Fig. 47). Compressed air from the cylinder enters the air distributor cavity through the central fitting (see Fig. 46) and then through the oval hole in the distribution disk and oblique holes in the housing to the air ducts of the cylinders.

Since, regardless of the position of the crankshaft, the disc hole always coincides with one or two holes in the housing, when the valve is opened, compressed air enters one or two cylinders, respectively, in the order of their operation. The air supply to the cylinders occurs 6 ± 3 ° before the east. m. t. at the end of the compression stroke and continues when the crankshaft rotates 114 °.

Rice. 41. Air distributor:
1 - fuel pump drive gear; 2 - distribution disk; 3 - clutch; 4 - air distributor roller; 5 - central air supply fitting; 6 - cover of the distribution disk; 7 - air distributor cap; 8 - fitting for supplying air to one of the cylinders; 9 - air distributor housing; 10 - fuel pump drive housing; 11 - hole; 12 and 13 - oblique holes; 14 - oval hole in the distribution disk

The moment of supplying compressed air to the engine cylinders by the air distributor is regulated in the following sequence.

Rice. 42. Start valve:
1 - nut; 2 - cap; 3 - spring; 4 - valve body; 5 - valve; 6 - compressed air supply fitting

Rotating the engine crankshaft along the course, set the piston of the 1 liter cylinder along the graduated flywheel flange to position 27 ° after c. m.t. on the expansion cycle.

Remove the cap, cover from the air distributor, pull out the pin and remove the washer, spring and coupling.

Install the distributor disk in such a position that the front (in the direction of rotation) edge of its hole coincides with the edge of the air supply hole in the 1l cylinder and the hole is completely open. In this case, the disc must select the gaps in the direction opposite to the direction of rotation (the distribution disc rotates counterclockwise).

Install the clutch, choosing a position in which it will engage with the splines of the roller and disk without turning them.

Check the correct installation of the distribution disk by first turning the crankshaft against the stroke by 30-40 °, and then setting it to its previous position.

If the distribution disc is installed correctly, put the remaining parts of the air distributor in their places.

TO Category: - BelAZ vehicles