Few of diesel engines boasts such a solid "track record" as YaMZ-238. This engine has become the "heart" of many thousands of MAZ, KrAZ, Ural trucks familiar to everyone and everyone; tractors "Kirovets" and "ChTZ"; combines "Don" and "Polesie". As well as a large number of all kinds of highly specialized equipment, boats, diesel power plants. YaMZ-238 is extremely reliable and unpretentious in operation, which provided him with a “long-liver career”: the engine launched into series in the early 60s continues to roll off the assembly line of Yaroslavsky engine plant and today. Despite the fact that a lot of more modern "successors" appeared in the assortment of the plant.

Yaroslavl Automobile Plant. So until 1958 this enterprise was called, which produced trucks, buses and trolleybuses. In many things, YaAZ became a pioneer. Here, in the 1920s, the production of the first heavy-duty vehicles (from 3 to 7 tons) in the Land of Soviets was launched. In the 1930s, the first dump trucks in the USSR left the assembly line of the plant; one and double-decker buses and trolleybuses.

The first diesel engine in the Union was also produced in Yaroslavl. Here, by the end of the 30s, diesel engines MD-23 domestic development for trucks and tractors have been tested and prepared for launch in a series. But mass production diesel engines was established only two years after the end of the Great patriotic war. During the war years, YaAZ gave the front lungs tracked tractors for artillery.

Since 1947, the plant has been running mass production families of 2-stroke four- and six-cylinder diesel engines YaAZ-204 and YaAZ-206 with power from 110 to 220 hp First of all, the developers of new families of motors - and YaMZ-238 - relied on the experience of their production and operation.

50s of the twentieth century. Workshop of the Yaroslavl Automobile Plant. In the photo - a 10-ton dump truck YaAZ-210

During 1958-1961, a group of scientists led by the outstanding Soviet designer and inventor Georgy Dmitrievich Chernyshev created and prepared for the launch in a series the best diesel engines in the world at that time: powerful, versatile, reliable and trouble-free. And also economical (for that time). For the development of these four-stroke six- (YaMZ-236) and eight-cylinder (YaMZ-238) engines with power from 180 to 500 hp. was awarded the State Prize of the USSR, and the plant was awarded the Order of Lenin.

Since that time, the history of the Yaroslavl Automobile Plant ended (the production of trucks was transferred to Minsk), and the history of the motor plant began. The scale and volume of production of universal diesel engines that were deployed here in Soviet time, strike the imagination. It is estimated that in total more than three hundred models of trucks, buses, tractors, and other vehicles were equipped with YaMZ engines.

In our time, YaMZ has retained the function of the enterprise full cycle: with its own foundry, forging press, thermal, welding, galvanic, painting, hardware, mechanical assembly, assembly and testing, tool, repair production. With energy facilities, transport and storage services, a developed network of sales and service points, with workshops for small machine tool building and non-standard equipment. YaMZ is part of the GAZ Group holding.

So, YaMZ-238 is a four-stroke eight-cylinder diesel engine with a classic V-shaped cylinder arrangement, direct fuel injection, compression ignition and liquid cooled. Available in both conventional "atmospheric" and turbocharged versions.

Year 2015. In the photo - YaMZ-238 / Euro 2 Turbo engines

In total, at the present time, the assortment of the plant, set out in the current official price list on the YaMZ website, includes 25 various modifications YaMZ-238 engine. Whole line turbocharged versions (DE series, for dump trucks and trucks, truck tractors MAZ, KrAZ, Ural; tractors and timber trucks) have been modified to Euro-2 standards. In total, the general list of modifications this motor has 86 items.

Varieties of motors of the YaMZ-238 family and their features

YaMZ-238 is the most demanded diesel engine of the Yaroslavl Motor Plant on the market. In technological terms, it is not much different from the YaMZ-236 series of six-cylinders (first of all, the number of cylinders, of course). The power of the basic versions of the YaMZ-238 varies from 180 hp. in the de-forced version of the YaMZ-238 / G2, up to 240 hp in the YaMZ-238 / M2 modification.

YaMZ-238 / Euro-0 Turbo engines are forced YaMZ-238 / M2 engines. They differ from the usual "atmospheric" not only in the presence of a turbine. During the development of this family, a number of constructive changes in the cylinder block and cylinder-piston group.

The fuel pump has also been reworked. high pressure and crankshaft. The assortment of the plant includes YaMZ-238 models with flywheels for the installation of 2-disk or single-disk clutches; with right-hand controls (by order from South Africa), and other constructive solutions, for the needs of each specific technique.

Motors of the YaMZ-238 / Euro-1 Turbo series are modified Euro-0. The features of their configuration is the installation of a liquid-oil heat exchanger, a fan clutch and air ducts to the cooler charge air mounted directly on the engine.

YaMZ-238 / Euro-2 Turbo engines, DE series, were the result of further modernization of the turbocharged YaMZ-238. The motors of this series received a modernized modern high-pressure fuel pump.

The device and layout of the main elements of YaMZ-238 engines

Eight cylinders YaMZ-238 are arranged in two rows, in a V-shaped pattern, at an angle of 90 degrees. Inlet fuel mixture and exhaust gases are provided by 16 valves.

The basis for the installation of all units and parts is the cylinder block, which is cast from low-alloyed gray cast iron. In the tides-bosses on the walls of the block, a system is provided oil channels, supplying lubricant to the bearings of the distributive and crankshaft; to the oil filter and to the liquid/oil heat exchanger.

A closed power belt is formed around each cylinder seat by the walls of the water jacket. Together with special ribs, the power belt fastens together the upper and lower plates (parts of the cylinder block), giving the entire structure the desired degree of rigidity. In the transverse walls of the block there are five nests with liners for the crankshaft main journals. As well as five bores with bronze bushings in which the camshaft.

cylinder heads YaMZ motor-238 - four-block, cast from gray cast iron with a ground surface and annular grooves. The gas joint of the head, block and cylinder liners is sealed by a single gasket with 19 sealing elements. The cylinder heads house the intake and exhaust valves with springs, rocker arms, rocker arms and injectors.

Saddles intake valves are made from cast iron of a special brand, graduation - are cast from a special heat-resistant alloy. Seats and metal-ceramic cylinder bushings are finally processed during their pressing into the head.

Crank mechanism

Pistons made of aluminum eutectic alloy are placed inside the cylinder liners, which are coated in YaMZ-238 with a special phosphated layer to enhance wear resistance. Oil is supplied to the piston from a special fixed nozzle. The groove for the upper (compression) ring is made in an insert made of heat-resistant cast iron of a special grade, such as "niresist". The number of rings, depending on the modification of the YaMZ-238 engine, is three or four. The piston pin is nitrided, with an increased outer diameter.

The I-section steel connecting rod has an oblique lower head connector. The connecting rods are finished after they are assembled with the cap, so the rod caps are not interchangeable. Replaceable liners are mounted in the lower head of the connecting rod, and a steel-bronze bushing 56 mm in diameter is pressed into the upper head.

Flywheels on YaMZ-238 are used in two types. Brand "K", for the ring gear with a module of 4.25. And brand "H", designed to work with the gear rim of the module 3.75. Flywheels are supplied complete with ring gears and are not interchangeable. The cast-iron flywheel is attached to the crankshaft with bolts, under which a high-strength steel plate is installed (one for all bolts). With respect to the crankshaft journals, the flywheel is fixed exactly with the help of two special pins.

Crank mechanism YaMZ-238

The steel crankshaft of YaMZ-238 engines is manufactured by hot stamping. All surfaces of the crankshaft are additionally processed and covered with a nitrided layer with a thickness of at least 0.35 mm. The crankshaft is equipped with five main bearings and four connecting rod journals. The system for balancing the crankshaft and saving (unloading) the main bearings includes, in addition to counterweights on the cheeks of the crankshaft, also two remote masses at the front and rear ends of the crankshaft.

Crankshaft YaMZ-238 engines of the BE and DE series are equipped with a cone at its front end, on which a hub is fixed, a liquid damper torsional vibrations and a special pulley.

The gas distribution mechanism of the YaMZ-238 engine

What elements does the gas distribution mechanism on YaMZ-238 consist of: this is a camshaft equipped with a drive gear and bearings; pushers with special axles; rods and rocker arms with adjusting screws; rocker axles; valves with springs, fasteners and guide bushings.

The camshaft is made of steel, forged, the bearing journals and cams of which are hardened by HDTV to increase wear resistance. It is installed at the top of the crankcase of the cylinder block. It is driven from the front end of the crankshaft, by means of special helical gears. The other listed elements of the gas distribution mechanism are also stamped, made of steel.

The inlet and outlet valves of the gas distribution mechanism are made from special heat-resistant alloys. The working chamfers of the valves are additionally welded with a particularly heat-resistant alloy of the Stellite type. Tips made of alloyed steel are welded to the rods.

Engine lubrication system YaMZ-238

The lubrication system at YaMZ-238 is of a mixed type, with a "wet" sump. Oil pump, having a working capacity of 140 liters per minute, sucks oil through the intake pipe from the lower part of the crankcase and supplies it under pressure to liquid-oil heat exchanger. From where, through the bypass valve, the oil is driven through special channels to the bearings, pushers and other working surfaces of the engine.

When the oil pressure rises above 520 kPa (5.2 kgf/cm2), excess oil is drained through the oil line back down the crankcase. To clean the oil from waste products, the presence of oil filter and an additional centrifugal oil filter.

The fuel supply system of the YaMZ-238 engines is of a split type. Its components are as follows: high pressure fuel pump (with built-in regulator and corrector); fuel pump; nozzles; coarse filters and fine cleaning diesel fuel; low and high pressure fuel lines.

The functioning of the YaMZ-238 power system is as follows. Diesel fuel is sucked from the fuel tank by the fuel priming pump, while passing through the original filter coarse cleaning fuel. Further, the fuel reaches the fine filter through the fuel line, passes through it and enters the high pressure fuel pump.

The injection pump, like a real fuel distribution station, in accordance with the order of operation of the cylinders, drives the fuel through the high pressure fuel lines to the injectors. Through which it is sprayed into the cavity of the cylinders. Through bypass valve in the fuel pump and the jet in the fine filter, excess diesel fuel, together with the air that has entered the system, is discharged through a special fuel line back to fuel tank. The same function is performed by the fuel line, which removes excess fuel that has leaked into the cavity of the injector spring.

Some parameters of YaMZ-238 in numbers

Displacement: 14.85 liters
Power range: 180-420 hp
Resource from the manufacturer: 800 thousand - 1 million km.
Overall dimensions, with gearbox and clutch (in brackets - without them), in millimeters: 1796-2069 (1020-1222) x 1006 x 1195.
Dry weight with auxiliary equipment (in brackets - without it), in kg - 880-1070 (820-1010).
Mass assembled and with transmission units, in kg 1170-1385.
The working volume of the lubrication system (without a radiator), in liters - 24-32.
The displacement of the cooling system (excluding the radiator-cooler and heater) is 17-20.

Specific application of YaMZ-238 engines: yesterday and today

Despite the abundance of modifications, design and technological diversity, YaMZ-238 engines, in most cases, are interchangeable with their predecessors, already removed from the assembly line. For example, variations of the YaMZ-238 / M2 model (of which there are 19 pieces - especially for Urals, river boats, MAZs, KrAZs, etc.) are interchangeable without problems not only with YaMZ-238 / M, produced until 1988, but also with YaMZ-238, the supply of which ceased in 1985.

Army "Ural-4320" with the YaMZ-238 engine

Of course, today there is no question of those huge volumes of production of eight-cylinder engines that the Yaroslavl Motor Plant successfully mastered in the years Soviet Union. However, in new Russia, in the face of fierce competition with foreign manufacturers, YaMZ-238 engines are in steady demand, continuing to be the main power units for new models of trucks and bulldozers, tractors and combines, road rollers and scrapers, diesel generators and drilling rigs, loaders and loggers, tracked all-terrain vehicles and armored personnel carriers, ship and mine vehicles, railway trolleys and track machines, road trains for underground works.

The YaMZ 238 engine is a power unit of a family of engines manufactured by the Yaroslavl Motor Plant. The YaMZ 238 motor is considered the older brother of the equally well-known YaMZ-236 power unit. They have similar technical characteristics, device of work and design features.

Historical aspect

The 238th model, like the younger brother of the 236th, replaced the outdated YaAZ-204 and YaAZ-206 engines. The development and implementation of the power unit began in the 50s of the 20th century, when it was necessary to make a powerful 4-stroke diesel engine with economical performance.

The legendary Soviet engineer, designer and inventor, Georgy Dmitrievich Chernyshev, is considered the father of the YaMZ family of engines. At that time, it was a unique motor of its kind, which was produced for half a century, and established itself as one of the best power units in the world.

To date, the YaMZ 238 engine has officially been discontinued, since Yaroslavl plant releases the receiver - YaMZ-530 and YaMZ-540. But, the production of spare parts continues, and the line will not stop, at least in the next 10 years.

Specifications

The technical characteristics of the YaMZ-238 engine have not changed over the entire period of production and upgrades. Of course, the motor was improved according to latest developments and innovation, but there were very few design changes. Consider the main characteristics of the power unit:

Name	Characteristic
Type of	Diesel, turbocharged diesel
Volume	15 liters (14,866 cc)
Configuration, parameter	V-shaped
Number of cylinders	8
Number of valves	16
Economy	from Euro-0 to Euro-4
Cylinder diameter	130 mm
Compression ratio	17,5
Cooling	liquid
valve mechanism	OHV
Block and head material	Cast iron
Resource	800,000 - 1,000,000 km
Fuel	Diesel fuel
The order of operation of the cylinders	1-5-4-2-6-3-7-8
Applicability	MAZ, KRAZ, URAL, T series tanks, K tractors, LAZ buses, CHETRA all-terrain vehicle and more

It is worth noting that all 238 series engines have a mechanical high pressure fuel pump. Each cylinder has its own pump section for even combustion. The injection pump is located between the rows of cylinders, on the collapse of the engine.

Motor modifications

ICE YaMZ 238 received a lot of modifications and applicability to car row. Yes, according to technical documentation manufacturer, consider which the lineup and the G8 engine has modifications:

235 HP (173 kW) at 1700 rpm, 1108 N m (113 kgf m) at 1300 rpm - YaMZ-238ND3.
235 HP (173 kW) at 1700 rpm, 1108 N m (113 kgf m) at 1300 rpm - YaMZ-238ND6.
240 HP (177 kW) at 2100 rpm, 882 N * m (90 kgf * m) at 1500 rpm - YaMZ-238 (base).
250 HP (184 kW) at 1900 rpm, 1108 N m (113 kgf m) at 1300 rpm - YaMZ-238ND4.
250 HP (184 kW) at 1900 rpm, 1108 N m (113 kgf m) at 1300 rpm - YaMZ-238ND7.
280 HP (206 kW) at 2100 rpm, 1029 N m (105 kgf m) at 1500 rpm - YaMZ-238PM.
290 HP (184 kW) at 2000 rpm, 1128 N m (115 kgf m) at 1400 rpm - YaMZ-238DK.
300 HP (220 kW) at 1900 rpm, 1280 N m (131 kgf m) at 1300 rpm - YaMZ-238ND5.
300 HP (220 kW) at 1900 rpm, 1280 N m (131 kgf m) at 1300 rpm - YaMZ-238ND8.
320 HP (235 kW) at 2100 rpm, 1117 N m (114 kgf m) at 1500 rpm - YaMZ-238FM.
330 HP (243 kW) at 2000 rpm, 1225 N m (125 kgf m) at 1400 rpm - YaMZ-238DK.
330 HP (243 kW) at 2100 rpm, 1225 N m (125 kgf m) at 1300 rpm - YaMZ-238D.
330 HP (243 kW) at 2100 rpm, 1225 N m (125 kgf m) at 1300 rpm - YaMZ-238DE.
330 HP (243 kW) at 2100 rpm, 1274 N m (130 kgf m) at 1200 rpm - YaMZ-238DE2.
330 HP (243 kW) at 1900 rpm, 1274 N m (130 kgf m) at 1200 rpm - YaMZ-6582.
360 HP (265 kW) at 1900 rpm, 1570 N m (160 kgf m) at 1200 rpm - YaMZ-7512.
400 HP (294 kW) at 1900 rpm, 1715 N m (175 kgf m) at 1200 rpm - YaMZ-7511.
400 HP (294 kW) at 1900 rpm, 1764 N m (180 kgf m) at 1200 rpm - YaMZ-6581.
420 HP (309 kW) at 1900 rpm, 1764 N m (180 kgf m) at 1200 rpm - YaMZ-7513.

Power unit maintenance

The YaMZ-238 engine does not have significant differences from the 236 model. Service maintenance of the engine is carried out every 20-25 thousand kilometers. Planned technical maintenance of internal combustion engines- a set of operations aimed at maintaining the primary state of units and parts of the unit. According to the manual for the repair and operation of the YaMZ motor compiled by the manufacturer, we will consider what operations are included in the maintenance of the G8:

Change of oil.
Replacement of filters. So, depending on the modification of the engine, there may or may not be the following filter elements: fine and coarse oil filter, filter element for coarse and fine fuel purification, air filter, exhaust ecofilter.
Nozzle cleaning.
High pressure fuel pump adjustments.
Other operations aimed at Maintenance power unit.

Servicing a high-pressure fuel pump is a separate set of operations that only masters in the repair of fuel equipment for diesel engines can do with high quality.

Engine repair: basic description

Repair of the YaMZ 238 engine is a whole range of operations to restore the engine's performance, which is not recommended to be done by hand. So, it is worth contacting professionals who can correctly diagnose malfunctions and wear, as well as what inner element needs to be replaced. Consider the main set of operations that is carried out for the YaMZ 238 motor in order to carry out overhaul motor:

Superficial fault diagnosis is carried out by ear. The motorist determines the presence extraneous noise, as well as the preliminary location.
Dismantling the motor from the car, as well as carrying out a complete disassembly of the power unit.
Measurements of cylinders and crankshaft. Determining the repair number, as well as ordering spare parts. As practice shows, in most cases, in order not to bore the engine cylinders, the block is sleeved. This parameter allows, and in the case of subsequent repairs, to bore not the block, but the sleeves, which, when worn, can be removed and new ones inserted.
Cylinder head repair.
Assembly of the power unit.

A separate parameter is the restoration of the injection pump. As practice shows, the master repairs only the plunger pair, which wears out most often.

As for in-line repair operations, each owner of a car with a YaMZ engine has sufficient skills and knowledge to restore his engine on his own, the main thing is that the hand grows from the right place. To the most common problems applies to:

Starter and alternator failure.
Failure of the water pump.
Replacing drive belts.
Valve mechanism adjustment.
Change of oil.
Replacing engine filters.

Repair instructions for each node are available on the Internet or you can use factory books that are publicly available.

Output

The YaMZ 238 engine is considered a legend domestic automotive industry. For more than half a century of production, the power unit has shown itself to be reliable and easily repairable. For these qualities, he fell in love with motorists.

It is worth noting that YaMZs, both 238 and 236, were often exported in large quantities. For example, China orders engines of this series for its heavy trucks, since only BELAZ and Caterpillar can compete with YaMZ, but they are much more expensive than their domestic counterparts.

YaMZ 238 engine

Characteristics of YaMZ-238

Production	"Autodiesel" Yaroslavl Motor Plant
Engine brand	238
Release years	1962-present
Block material	cast iron
engine's type	diesel
Configuration	V-shaped
Number of cylinders	8
Valves per cylinder	2
Piston stroke, mm	140
Cylinder diameter, mm	130
Compression ratio	16.5
Engine volume, cc	14866
Engine power, hp / rpm	235/1700 240/2100 250/1900 280/2100 290/2000 300/1900 320/2100 330/2000 330/2100 330/2100
Torque, Nm/rpm	1108/1300 882/1500 1108/1300 1029/1500 1128/1400 1280/1300 1117/1500 1225/1400 1225/1300 1274/1200
Environmental regulations	Euro 0 Euro 1 Euro 2
Turbocharger	K27-49 K36-87 TKR 11 TKR 122
Engine weight, kg	1075 (YaMZ-238M2)
Fuel consumption at a speed of 60 km/h, l/100 km (for URAL 4320)	38
Oil consumption, % of fuel consumption, up to	0.5 0.2 (Euro 2)
Engine oil: -summer -in winter (less than +5°C)	M-10-G2k M-8-G2k
How much oil is in the engine, l	29 (atmospheric) 32 (turbocharged)
Oil change is carried out, hours	500 1000 (Euro 2)
Dimensions, mm: - length - width - height	1315 1045 1070
Engine resource - according to the factory, hours - in practice, thousand km	8 000 800+
Tuning, HP - potential - no loss of resource	300+ ~280
The engine was installed	Combines Don, Kuban, Khersonets, Slavutich, Palesse MAZ-5336, 5432, , , , 5552 MAZ-6303, 6317, 6422, 6425, MoAZ-740, 1405, 6014, 6442, 7505 MoAZ-40484, 40489, 49011 KrAZ-260M, 5133, 5444, 6130, 6133, 6305, 6322 KrAZ-6351, 6443, 6446, 6503, 6505, 7133, 7140 EO-412, 511, 512, 522 Ural-4320, 5323, 5423, CHETRA-60, T15, T20, TG-221 Kranex EK400 Roll REM25 GT-TM, GT-TMS and MGSH521M1 MT-LBu, MT-LB EXCO BM-2501 ML-107 TG-301 MZKT-692378 HTZ 181 ChSDM DZ-240S Kirovets K-700, 702, 703, 740, 744 DZ-98V Boats KS-101, 104, 110 AD-100, DGU-100 ADM-1.5, MPG-6 VPR-02, VPRS-02, 03

Reliability, problems and repair of YaMZ-238

The YaMZ-238 series was put into production in 1962 and replaced the YaAZ-206. This motor has a V-shaped 8-cylinder cast iron block, with a camber angle of 90°, with wet cast-iron liners and with an offset of the cylinder rows relative to each other by 35 mm. Inside the block, on 5 supports, a forged crankshaft with a piston stroke of 140 mm and a diameter of the main journals of 110 mm and a diameter of the connecting rod journals of 88 mm is installed, the connecting rods themselves are steel, and their length is 265 mm. For these motors, cast aluminum pistons with a diameter of 130 mm and a height of 100 mm were used, the diameter of the piston pin was 50 mm.

The cylinder block is covered with two cast-iron heads with 8 valves each. Inlet valves diameter 61 mm, exhaust valves 48 mm, stem diameter 12 mm.
Here, a camshaft gear drive is used, and the camshaft itself is located in the cylinder block and, through pushers, steel rods and steel rocker arms, actuates the valves. Camshaft characteristics: phase 246/266, rise 13.5 mm.
Valve adjustment on YaMZ-238 (turbo and atmospheric) is carried out after every 500 hours of operation (if necessary). Valve clearances for both intake and exhaust are 0.25-0.3 mm. The order of adjustment is 1-5-4-2-6-3-7-8, the same as the order of operation of the cylinders (both turbocharged and aspirated).
These engines use direct fuel injection with a high-pressure fuel pump 80-30 (on the YaMZ-238M2) or with other pumps (details on modifications are described below).
Nozzle pressure 261 - 230 kgf / cm 2; nozzles 267 - 270 kgf / cm 2.
The oil pressure on a warm engine should be in the range of 4-7 kgf / cm 2 (this applies to both turbo and atmosphere).

In addition to atmospheric options, turbocharged ones were also produced, the list of which knows no bounds. The main differences between them are listed below.

This motor had a related YaMZ-236 series.

The release of the 238th continues now, but they are being replaced with more environmentally friendly YaMZ-7511 and YaMZ-658.

Modifications of YaMZ 238 and their differences

1. YaMZ-238AK - an analogue of YaMZ-238M2 under Euro-0 standards, which was intended for combines Don, Kuban, Khersonets, Slavutich and Palesse FS60. Power 235 hp at 2000 rpm, torque 932 Nm at 1300-1500 rpm. The service life of the motor before overhaul is 8000 hours.
2. YaMZ-238AM2 - version of YaMZ-238M2 with a power of 225 hp. at 2100 rpm, torque 825 Nm at 1250-1450 rpm. Ecological class - Euro-0, and its resource is 8000 hours.
Stands on MoAZ-6014 and 6442.
3. YaMZ-238B - turbocharged engine based on YaMZ 238M2, where a TKR 100 turbocharger is used. A modified camshaft with the following characteristics is installed here: phase 240/266, nozzles 261-13, another crankshaft, its own pistons, pump 807-40. The motor complies with the Euro-0 standard.
You can meet him at VPR-02, VPRS-02 and 03; MAZ-5336 and 5432; MoAZ-40484, 40489, 49011 and 7505; KrAZ 5444, 6130, 6503 and 6505; ADM-1.5, MPG-6, EO-5225, Ural 5323 and 5423; CHETRA T20, EK400 and REM25. Motor resource - 450 thousand km.
4. YaMZ-238BV - analogue of 238BL, but with injection pump 807-40. Installed on GT-TM, GT-TMS and MGSH521M1. Resource - 8000 hours.
5. YaMZ-238BE - the same YaMZ-238B, but with a built-in liquid-oil heat exchanger and modified cooling and lubrication systems. Here, an injection pump YAZDA 807-50, nozzles 261-13 and a turbine TKR 122 are used. The boost pressure is 0.93 bar. Power 300 hp at 2000 rpm, torque 1180 Nm at 1200-1400 rpm. The engine meets Euro-1 requirements.
6. YaMZ-238BE2 - an engine with a different crankshaft and connecting rods, with liners protruding 1.6 mm above the surface of the block, with other pistons (height 85 mm), the diameter of the piston pin is increased to 52 mm. Also here, a cylinder head with annular grooves, a high-pressure fuel pump YAZDA 173-20, injectors 267-01, a camshaft with a phase of 233/272, and another coarse fuel filter were used. The power remained the same, and the torque increased to 1274 Nm at 1100-1300 rpm. This option meets Euro-2 standards.
7. YaMZ-238BK - a motor for Polesie combines, which meets Euro-0 standards. It is equipped with a TKR-100 turbine and high-pressure fuel pump 805-40. The 238BK-3 versions use two K27-49 turbines. The resource of such an engine is 8000 hours.
8. YaMZ-238BL - the same 238B, but with high pressure fuel pump 801-50, with a deep crankcase and a different fan drive. Power increased to 310 hp at 2100 rpm, torque 1177 Nm at 1200-1400 rpm. Found on MT-LBu.
9. YaMZ-238BN - a turbo engine for MoAZ 7529 with a TKR 100-16 turbine. Power 260 hp at 2000 rpm, torque 1080 Nm at 1200-1400 rpm. Resource - 8000 h.
10. YaMZ-238VM - analogue of YaMZ-238M2 with a different oil pan. Intended for MT-LB. Serves up to overhaul 5000 hours.
11. YaMZ-238GM2 - the same YaMZ238M2, but with a differently adjusted fuel (TNVD 809-20). Power reduced to 180 hp at 1700 rpm. It is found on excavators EO-412, 511, 512, 522 and drilling equipment BM-2501. Service life 5000 hours.
12. YaMZ-238D - the same 238B, but under the YaMZ 202 checkpoint and with high-pressure fuel pump 806-40. ICE resource- 450 thousand km.
Stands on ML-107, TG-301, MZKT-692378, MAZ-53363, 54323, 5552, 6303 and 64229; KrAZ-5133, 5444, 6130, 6322, 6351, 6443, 6505 and 7133.
13. YaMZ-238DE - the same YaMZ-238BE, but with a high pressure fuel pump YAZDA 806-50 and a boost pressure of 1.08 bar. Power increased to 330 hp at 2100 rpm, torque 1225 Nm at 1200-1400 rpm. The engine complies with the Euro 1 environmental class and is found on MAZ 5336, 5432, 5516, 5551, 6303, 6317, 6422, 6425 vehicles and Polesie combines. The declared resource is 800 thousand km.
14. YaMZ-238DE2 - the same 238BE2, but with high pressure fuel pump YAZDA 173-30. Compared to the 238DE, the power remained unchanged, the torque reached 1274 Nm at 1100-1300 rpm. Upgraded here environmental class up to Euro 2, and the resource is 800 thousand km.
Such an internal combustion engine is installed on KrAZ 5133, 5444, 6130, 6133, 6305, 6322, 6443, 6446, 6503, 6505, 7133, 7140, as well as on MAZ-5336, 5432, 5516, 5551, 6303, 6317, 6425.
15. YaMZ-238DI - the same 238B, but with a K36-30 turbine and an 803-30 injection pump.
16. YaMZ-238DK - a combine motor for the Don 680M, an analogue of the YaMZ-238BK, but the power has been increased to 330 hp. at 2000 rpm, torque 1225 Nm at 1300-1500 rpm.
17. YaMZ-238IM2 - a motor for diesel power plants AD-100 and DGU-100, its resource is 25,000 hours.
18. YaMZ-238KM2 - analogue of YaMZ-238M2, but adapted to work on MoAZ-1405, 740 and KhTZ 181 vehicles. Power 190 hp at 2100 rpm, torque 687 Nm at 1250-1450 rpm. ICE resource - 8000 hours.
19. YaMZ-238L - multi-fuel engine for KrAZ-260M. It is equipped with a TKR-11 turbine and an 801-11 pump.
20. YaMZ-238M2 - the engine that replaced the YaMZ-238M in 1988, its environmental class is Euro 0. The engine is on the ChSDM DZ-240S, MoAZ-6442 and 6014.
21. YaMZ-238MS - option for northern latitudes.
22. YaMZ-238N - turbo engine with injection pump 804-21 and TKR 11, power 300 hp at 2100 rpm, torque 1078 Nm at 1500 rpm.
23. YaMZ-238ND3 - a turbocharged engine based on 238B, which does not have oil cooling pistons and a liquid-oil heat exchanger. The turbine TKR 11 and high pressure fuel pump 805-30 are installed here, and the motor meets the requirements of Euro 0. The motor resource of the engine is 8000 hours. Power 235 hp at 1700 rpm, torque 1108 Nm at 1100-1400 rpm. There is an engine for K-700, 702, 703 and DZ-98V.
24. YaMZ-238ND4 - a turbocharged engine with a liquid-oil heat exchanger based on 238ND3. There is a high-pressure fuel pump 805-40, and the environmental class is Euro 0. It is found on K-744, K-703, KS-101, KS-104, KS-110, T15.01, T-221 and Chetra-60. The resource of the motor is 8000 hours, and its output is 250 hp. at 1900 rpm, torque 1108 Nm at 1100-1400 rpm.
25. YaMZ-238ND5 - turbo engine based on 238B-1. It was equipped with high pressure fuel pump 805-50, its generator, crankcase, crankshaft pulley and had a resource of 8000 hours. Motor power 300 hp at 1900 rpm, torque 1280 Nm at 1100-1400 rpm. They put it on the K-744R1.
26. YaMZ-238ND6 - turbo engine for Euro-1, developed on the basis of YaMZ-238DE. It differs from the parent engine in a generator, crankcase, flywheel, pump 805-60 and a resource of 10,000 hours. Power is 235 hp. at 1700 rpm, torque 1108 Nm at 1100-1400 rpm. There was an engine on the K-740.
27. YaMZ-238ND7 - 250 hp version at 1900 rpm, the moment is the same. The pump 805-70 is used here, and this internal combustion engine is installed on the Kirovets and T15.01 tractors, as well as on the TG-221.
28. YaMZ-238ND8 - a model with a pump 805-80 for 300 hp at 1900 rpm, torque 1280 Nm at 1100-1400 rpm. This option is on Kirovets and goes to overhaul 10,000 hours.
29. YaMZ-238NP - a motor created on the basis of 238ND2 and is distinguished by a turbine nozzle and a generator.
30. YaMZ-238PM - a turbo engine with a TKR9 turbine with a power of 280 hp. at 2100 rpm, torque 1029 Nm at 1500 rpm. Replaced by 238B.
31. YaMZ-238FM - the same 238PM, but with oil nozzles, power increased to 320 hp. at 2100 rpm, torque 1118 Nm at 1500 rpm. The motor was replaced with a 238D.

Malfunctions YaMZ-238

1. The engine is warming up. The causes of overheating are often in a dirty radiator, pump or thermostats. Check and most likely the problem will be here. If not, then you need to look at the cylinder head gasket and the condition of the heads for cracks.
2. Swim speed. The reason is the injection pump, you need to check how it is adjusted and adjust the idle speed with a screw on its back. Another reason is air in the fuel system.
3. Does not develop momentum. You need to check how the pump is configured, replace filters, and look at the fuel system.
4. Twitching at low speeds. In this case, you need to start with the fuel (pump, injectors, etc.) and with the ignition.
5. Troit. Perhaps the reason is a lack of fuel and you need to pay attention to the high pressure fuel pump, to fuel filters, on nozzles or on tubes.
6. Stalls or starts and stalls. Check for air leaks, see fuel filters, pump, sometimes something extraneous could get into the tank.
7. Knocking in the engine. The reasons may be in the nozzles, pump, ignition, valves, rings, liners; You have to open up the engine and have a look.
8. Smokes:
- white smoke- perhaps you have water in the tank or coolant entering the cylinders through a gasket or cracked cylinder head.
- black smoke- you need to reduce the fuel on the injection pump using the lower power screw, most likely it is turned to the maximum.
- blue smoke You probably have an oil burn.
9. Vibration. The reasons are usually in the flywheel, in the ignition, in the engine mounts, in cardan shaft maybe the crankshaft is out of balance.
10. Won't start. The cause must be sought in the injectors and the pump.
11. Cracks in the cylinder head. Typical fault for these internal combustion engines, it is formed on the intervalve jumper, but, fortunately, this issue can be tried to be solved, there are many companies that are ready to restore the head.

Despite the long list various faults, it is very reliable and durable motor. YaMZ-238, with adequate care and maintenance, has a resource in practice of 800-900 and even 1 million km.

Engine number YaMZ-238

The number is located in the flywheel area, on the left.

Tuning YaMZ-238 engines

How to install a turbine

To convert an ordinary atmospheric 238 into a turbo, you can leave the standard pistons, you can do without oil nozzles, just put the TKR 36-87 turbine with manifolds from YaMZ-7511, make oil drain and oil supply to the turbine, put 261 sprayers, set up the injection pump and drive as is. So you can get 280-300 hp. It will even ride for years without problems, but for more high reliability it is better to replace the pistons with 238B.

YaMZ engines are produced by the Yaroslavl Motor Plant. They are used on the overall trucks KRAZ, MAZ, MZKT, and on construction equipment and taps.

A variety of models and modifications provides high performance technology in all operating conditions. According to its design and principle of operation, the engine meets environmental international standards Euro-0.

1 Description of the design and features of the YaMZ engine

A series of four-stroke diesel engines YaMZ is represented by two YaMZ models 236 and YaMZ 238. The first unit is equipped with six cylinders. The second model has eight cylinders. Both versions have fluid system cooling.

1.2 Performance characteristics of the YaMZ 238 engine

According to their technical characteristics of YaMZ 238 is ahead of many manufacturers. The working qualities of the motor are as follows:

the working volume of the motor cavity is 14,866 cm 3;
torque reaches 31 rpm (maximum speed - 2100 rpm);
the power range of the unit is 235-420 horsepower / 220 kW;
the diameter of the used cylinders is 130 mm;
the piston stroke in the cylinder is 140 mm;
the standard assembly is designed for a mileage of 800 thousand kilometers without repair and replacement of components;
optimal fuel consumption is 175 g / hp per hour;
the mass of the device is 1050 - 1120 kg (depending on the modification);
the volume of the water cooling system is 44.5 l;
volume lubrication system- 32 l.

The motor is equipped with a YaMZ double-disk clutch, equipped with a special torsional vibration damper. Clutch type - dry, diaphragm with a pull-out principle of operation. The diameter of the discs is 400 mm.

2 The main modifications of the YaMZ 238 motor

Model 238 is the founder of a number of modifications and configurations that are designed to work in various climatic conditions, with varying degrees of complexity of work. Also, the distribution takes place depending on the characteristics of the equipment for which the modification is designed.

The main engine options are:

YaMZ 238. Is standard equipment motor.
YaMZ 238 Turbo. The engine is distinguished by a gas blower system, which allows you to more efficiently cool the working units. It also differs from the standard model in the parameters of the valves and the fuel pump.
YaMZ 238m2. Differs in reduction of fuel consumption. This indicator for the 238m2 model is 157 g/hp per hour. Applicable to railway vehicles construction machines and cranes, for forage harvesters.
YaMZ 238nd5. The engine is also equipped with a turbocharging system and can be equipped with a power take-off. The installation of the motor is done mainly on the tractor. Can be used with ZIL 4331.
YaMZ 238 de. Applies exclusively to car engines. The filtering mechanism has been improved, which allows you to work in polluted conditions.
YaMZ 238 Euro-2. Features an improved fuel pump.

2.1 Main engine problems and their solution

In terms of its wear resistance and build quality, YaMZ 238 takes quite high level. But, with excessive loads on the equipment and violation of the operating rules, problems may arise in the operation of the motor.

For example, the incorrect position of the valves of the engine cylinders. The optimal valve clearance is in the range of 0.25-0.30 mm. If such a gap is increased or, on the contrary, smaller, the valves need to be adjusted.

The adjustment procedure is as follows:

first of all, the power device is cooled to 20 degrees;
the valve cover is removed;
timing tightening is checked;
then the clamp of the nut at the far end of the rocker is loosened;
a rod with a thickness of 0.25 - 0.3 mm is inserted between the lever and the surface of the piston;
the screw of the lever is tightened with a screwdriver until it comes into contact with the rod;
then you need to carefully tighten the nut on the rocker arm (so as not to turn the screw);
the set clearance is measured again.

The valves are adjusted in the order 1-5-4-2-6-3-7-8. One full turn screw is 360 degrees. When adjusting, it is necessary to accurately fix the angle of rotation for each adjustable valve according to this indicator.

To less serious problems relate:

Clogged fuel line and fuel intake. The system is removed from the motor and thoroughly blown/washed.
Fuel filters are clogged. Replaced with a new one (in last resort- cleanup of the old).
Fuel pump failure. Replace the spare part with a new one.
Clogged injectors with a violation of the fuel supply. Clean nozzles and adjust correctly. At YaMZ 238, adjustment is carried out in the workshop.
Piston rings wear out. Purchase and replacement of compression rings with new ones.
Manometer failure. Either repair in the workshop, or buy a new one.

The most widespread of the engines of the Yaroslavl Motor Plant is the family of YaMZ-238 diesel engines. If you look at YaMZ-238 without touching technical parameters, then it differs slightly from the YaMZ-236 family - they simply added one cylinder to each row to the V-shaped six-cylinder unit, thus obtaining an eight-cylinder one.
All eight-cylinder engines of the YaMZ-236 series, regardless of the presence of turbocharging, have the same volume - 14.86 liters and a dimension of DxS 130 by 140 mm, a camber angle of 90 ° and 135 ° relative to the vertical axis.
The technical characteristics of the engines of the YaMZ-238 family differ quite a lot. Atmospheric diesel YaMZ-236 base engine family is atmospheric YaMZ-238 Euro-0. Its power range is from 180 hp. in the derated version of the YaMZ-238G2, up to 240 hp for YaMZ-238M2 models.
The scope of application of YaMZ-238 atmospheric engines is extensive, they are used: - YaMZ-238M2 modifications as a power unit for motor vehicles moving like on roads common use, and in off-road version (with fordability up to 1.4 meters deep), as industrial motors for driving drilling, pumping units and compressor stations, in diesel power plants, as marine diesel; - YaMZ-238GM as an engine for road and excavator equipment; - YaMZ-238KM as a diesel engine for underground dump trucks; - YaMZ-238AK and YaMZ-238AM as a combine motor.
Unlike the YaMZ-236 family, the YaMZ-238 family also includes turbocharged engines with Euro-0 performance. These are well-known "super" engines for MAZ of the YaMZ-238D and YaMZ-238B series with a significant range of modifications. In addition to them, this group should also include the engines of the YaMZ-238ND series (3, 4 and 5), which are widely used as part of wheel loaders, agricultural tractors, forest harvesting and road-building equipment. The YaMZ-238ND4-4 model was created as a marine engine and is used on boats of the KS type. YaMZ-238DK modifications are designed for power vehicles and combines, and YaMZ-238DI are installed on diesel power plants (diesel generators).
With the seeming simplicity of using a turbocharger to increase power, this entailed a whole range of measures to change the design of a diesel engine and improve the quality of parts. Improved quality criteria primarily affected the following spare parts: crankshaft, cylinder block and cylinder-piston group.
To match environmental requirements Euro-1 turbocharged YaMZ-238 engines have undergone additional refinement. The design of the engines was supplemented by a liquid-oil heat exchanger and a high-performance water pump, a cylinder-piston group with efficient system cooling. The inclusion of the fan impeller drive is provided by a special clutch. In addition to turbocharging, the YaMZ-236 diesel engine received a charge air cooler, which is installed directly on the product that uses the power unit. It was also required to increase the injection energy into the combustion chamber, for which it was designed fuel equipment new type.
Engines of the YaMZ-238ND Euro-0 series have undergone additional modernization and the YaMZ-238ND models (6, 7 and 8) comply with more stringent environmental requirements, which made it possible to use them in a larger segment of equipment: on agricultural tractors, loaders, as part of wheeled vehicles at their base. By a similar modernization, YaMZ-238DE motors were obtained from the YaMZ-238D engine. All motors of the YaMZ-238DE series, with the exception of the YaMZ-238DE-21 modification (used for a forage harvester), are used as part of motor vehicles. All these power units belong to Euro-1.
The use of a more efficient high-pressure fuel pump (HFP) allowed the YaMZ-238 family of diesel engines to achieve Euro-2 performance. The series received the designation YaMZ-238DE2, all engines of the series were used exclusively in road transport.
At present, YaMZ-238 engines on automobile factories are not supplied due to stricter requirements for environmental parameters, are used as replacement part, as well as in places where not such hard limits- for example in production road equipment or diesel power plants.

The device of diesel engines YaMZ-238

The YaMZ-238 engine has eight cylinders, with a combustion chamber displacement of 1858 cm³ each. The principle of operation is four-stroke, characteristic of Otto engines, the order of operation of the cylinders is 1-3-6-2-4-5-7-8, direct injection, compression ratio 16.5.
Cylinder-piston group (CPG) with a piston made of silumin (aluminum-silicon alloy) and cast iron sleeve the so-called "wet type". The CPG is attached to a two-tee connecting rod, cast from cast iron with a special bronze insert, using a “floating type” pin with two retaining rings. The other side of the connecting rod is attached with two bolted connections to the crankshaft journal through liners (bronze plain bearings). The cylinders are arranged in two rows of four each.
There is one common cylinder head (cylinder head) for each row. The camshaft has a gear drive and is the same for both cylinder heads. The crankshaft is forged with nitrogen-reinforced journals, has five support points and counterweights. The cylinder block is cast in gray cast iron at the same time as the upper part of the crankcase. The block of cylinders of release till 2008. differs from modern (unified, has a shortened "skirt"). The flywheel housing is cast separately from the block. A steel flywheel with a separate ring gear (used for starting the engine) is made in two versions: for a double-disk clutch (wide) and for a single-disk (narrow). Fuel system motor YaMZ-238 mechanical plunger type. The YaMZ-236 engine has water system cooling and oil system mixed type lubricants (under pressure and spray method), water and oil radiator installed separately from the engine.

Detailed from technical specifications and the scope of YaMZ-238 engines, see the page of the required model.