Power units are designed for operation at ambient temperatures from minus 60ºС to plus 50ºС, relative humidity up to 98% at a temperature of 25ºС, air dust content up to 0.4 g / m 3, as well as for movement car in mountainous conditions at an altitude of up to 4500 m above sea level and overcoming passes up to 4650 m above sea level with a corresponding decrease in power and economic indicators.

Main parameters and characteristics of YaMZ-238 engines

Long service life and reliable operation of the engine depend on timely maintenance.

Maintenance work is preventive, so it must be done on time.

Daily maintenance is carried out once a day.

Maintenance after engine break-in.

First maintenance (TO-1) is performed every 500 hours of engine operation.

The second maintenance (TO-2) is carried out after 1000 hours of engine operation.

Seasonal maintenance is carried out before winterization and during the transition to summer.

Cylinder numbering scheme

Cylinder numbering scheme: A - right row of cylinders; C - left row of cylinders; B - flywheel

Cooling system

Liquid, closed type, with forced circulation of coolant

Equipped with a thermostatic device to automatically maintain the thermal regime of the engine

Water pump:

Centrifugal type, belt driven

Fan:

Six-bladed, with gear drive and friction clutch for turning on the fan

Liquid-oil heat exchanger:

Plate or tubular type. Equipped with a faucet or plug for draining the coolant

Thermostats:

With solid filler. Opening temperature 80ºС.

Electrical equipment

Single-wire circuit. Rated voltage 24V

Generator:

Alternating current, with a two-strand belt drive, with a rated voltage of 28V.

The model of the generator is determined by the configuration.

Launcher:

Electric starter model 25.3708-21 or AZF 4581 manufactured by Iskra (Slovenia), rated voltage 24 V.

It is allowed to use the ST-142D starter.

To facilitate starting a cold engine, an electric torch device is provided

Weight of the unfilled power unit in the scope of delivery, kg:

With individual cylinder heads:

  • - without clutch and gearbox - 1250
  • - with clutch - 1295
  • - with clutch and gearbox - 1685

With common cylinder heads:

- without clutch and gearbox

  • YAMZ-238BE - 1180
  • YaMZ-238BE2 - 1215
  • YAMZ-238DE - 1180
  • YAMZ-238DE2 - 1215

- with clutch

  • YAMZ-238BE - 1225
  • YAMZ-238BE2 - 1260
  • YAMZ-238DE - 1225
  • YAMZ-238DE2 - 1260

- with clutch and gearbox

  • YAMZ-238BE - 1580
  • YaMZ-238BE2 - 1615
  • YAMZ-238DE - 1580
  • YAMZ-238DE2 - 1615

Filling capacities, l:

  • lubrication system - 32
  • cooling system without water cooler volume - 22
  • advanced clutch injection - 0.14
Overall dimensions (mm) of YaMZ-238BE2, YaMZ-238BE, YaMZ-238DE2, YaMZ-238DE power units

YAMZ-238BE engine

Engine type - four-stroke, compression-ignition, turbocharged

Number of cylinders - 8

Cylinder arrangement - V - figurative, camber angle 90º

Cylinder firing order - 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right-hand

Cylinder diameter - 130 mm

Piston stroke - 140 mm

Displacement - 14.86 l

Compression ratio - 16.5

Rated power 220 (300) kW (hp)

Crankshaft speed at rated power 2000+50/-20 min -1

Maximum torque - 1180 (120) Nm (kgcm)

Speed at maximum torque - 1200-1400 min -1

Idle speed:

  • - maximum, no more than 2175 min -1
  • - minimum 600±50 min -1

Specific fuel consumption by speed characteristic, g/kWh (g/hp.h):

  • -minimum 206.7 (152);
  • - at rated power 227 (167)

Specific oil consumption for waste in % of fuel consumption, no more than 0.5

Method of mixture formation - direct injection

Combustion chamber - undivided type in piston

Camshaft - one for both gear-driven cylinder banks

Valve timing:

Inlet valves

  • - opening, deg to TDC 20
  • - closing, hail after BDC 40

Exhaust valves

  • - opening, deg to HMT 66
  • - closing, degrees after TDC 20

Number of valves per cylinder - one intake and one exhaust

Thermal valve clearances on a cold engine 0.25 - 0.30 mm

Lubrication system:

Mixed, with oil cooling in a liquid-oil heat exchanger:

- bearings of the crankshaft, camshaft, pushers, rocker axles, spherical surfaces of pusher rods, high pressure fuel pump, turbocharger are lubricated under pressure.

The rest of the rubbing surfaces are lubricated by splashing.

Oil pump gear type, single section

Oil pressure on a warm engine in the block line, kPa (kgf/cm 2):

  • - at rated speed - 400-700 (4-7);
  • - at minimum speed, not less than - 80 (0.8)

Oil filters - full-flow cleaning filter with filter element and centrifugal cleaning filter

Oil cooling system with liquid-oil heat exchanger, which is mounted on the engine block on the left

Oil pressure for opening lubrication system valves, kPa (kgf/cm 2):

  • - oil pump pressure reducing valve - 700-800 (7.0-9.0);
  • - differential valve - 490-520 (4.9-5.2);
  • - oil filter bypass valve - 200-250 (2.0-2.5)

Fuel supply system - split type

High pressure fuel pump (high pressure fuel pump) with regulator and fuel priming pump

Eight-section, plunger, spool-type plungers:

  • - plunger diameter 10 mm, plunger stroke 11 mm - YaMZ-238BE, YaMZ-238DE;
  • - plunger diameter 12 mm, plunger stroke 14 mm - YaMZ-238BE2, YaMZ-238DE2

YAMZ-238BE2 engine

Engine type - four-stroke, compression-ignition, turbocharged

Number of cylinders - 8

Cylinder arrangement - V - figurative, camber angle 90º

Cylinder firing order - 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right-hand

Cylinder diameter - 130 mm

Piston stroke - 140 mm

Displacement - 14.86 l

Compression ratio - 16.5

Rated power 220 (300) kW (hp)

Crankshaft speed at rated power 2000+50/-20 min -1

Maximum torque - 1274 (130) Nm (kgcm)

Rate at maximum torque - 1100-1300 min -1

Idle speed:

  • - maximum, no more than 2340 min -1
  • - minimum 650-700 min -1

Specific fuel consumption by speed characteristic, g/kWh (g/hp.h):

  • -minimum 195 (143);
  • - at rated power 223 (164)

Specific oil consumption for waste in % of fuel consumption, no more than 0.2

Method of mixture formation - direct injection

Combustion chamber - undivided type in piston

Camshaft - one for both gear-driven cylinder banks

Valve timing:

Inlet valves

  • - opening, deg before TDC 21.5
  • - closing, deg after BDC 31.5

Exhaust valves

  • - opening, deg to HMT 63
  • - closing, deg after TDC 29.5

Number of valves per cylinder - one intake and one exhaust

Thermal valve clearances on a cold engine 0.25 - 0.30 mm

Lubrication system

Mixed, with oil cooling in a liquid-oil heat exchanger:

- bearings of the crankshaft, camshaft, pushers, rocker axles, spherical surfaces of pusher rods, high pressure fuel pump, turbocharger are lubricated under pressure.

The rest of the rubbing surfaces are lubricated by splashing.

Oil pump gear type, single section

Oil pressure on a warm engine in the block line, kPa (kgf/cm 2):

  • - at rated speed - 400-700 (4-7);
  • - at minimum speed, not less than - 80 (0.8)

Oil filters - full-flow cleaning filter with filter element and centrifugal cleaning filter

Oil cooling system with liquid-oil heat exchanger, which is installed on the engine block left

Oil pressure for opening lubrication system valves, kPa (kgf/cm 2):

  • - oil pump pressure reducing valve - 700-800 (7.0-9.0);
  • - differential valve - 490-520 (4.9-5.2);
  • - oil filter bypass valve - 200-250 (2.0-2.5)

Fuel supply system - split type

High pressure fuel pump (high pressure fuel pump) with regulator and fuel priming pump

Eight-section, plunger, spool-type plungers:

  • - plunger diameter 10 mm, plunger stroke 11 mm - YaMZ-238BE, YaMZ-238DE;
  • - plunger diameter 12 mm, plunger stroke 14 mm - YaMZ-238BE2, YaMZ-238DE2

YAMZ-238DE engine

Engine type - four-stroke, compression-ignition, turbocharged

Number of cylinders - 8

Cylinder arrangement - V - figurative, camber angle 90º

Cylinder firing order - 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right-hand

Cylinder diameter - 130 mm

Piston stroke - 140 mm

Displacement - 14.86 l

Compression ratio - 16.5

Rated power 243 (330) kW (hp)

Crankshaft speed at rated power 2100+50/-20 min -1

Maximum torque - 1225 (125) Nm (kgcm)

Speed at maximum torque - 1200-1400 min -1

Idle speed:

  • - maximum, no more than 2275 min -1
  • - minimum 600±50 min -1

Specific fuel consumption by speed characteristic, g/kWh (g/hp.h):

  • -minimum 206.7 (152);
  • - at rated power 227 (167)

Specific oil consumption for waste in % of fuel consumption, no more than 0.5

Method of mixture formation - direct injection

Combustion chamber - undivided type in piston

Camshaft - one for both gear-driven cylinder banks

Valve timing:

Inlet valves

  • - opening, deg to TDC 20
  • - closing, hail after BDC 40

Exhaust valves

  • - opening, deg to HMT 66
  • - closing, degrees after TDC 20

Number of valves per cylinder - one intake and one exhaust

Thermal valve clearances on a cold engine 0.25 - 0.30 mm

Lubrication system

Mixed, with oil cooling in a liquid-oil heat exchanger:

- bearings of the crankshaft, camshaft, pushers, rocker axles, spherical surfaces of pusher rods, high pressure fuel pump, turbocharger are lubricated under pressure.

The rest of the rubbing surfaces are lubricated by splashing.

Oil pump gear type, single section

Oil pressure on a warm engine in the block line, kPa (kgf/cm 2):

  • - at rated speed - 400-700 (4-7);
  • - at minimum speed, not less than - 80 (0.8)

Oil filters - full-flow cleaning filter with filter element and centrifugal cleaning filter

Oil cooling system with liquid-oil heat exchanger, which is mounted on the engine block on the left

Oil pressure for opening lubrication system valves, kPa (kgf/cm 2):

  • - oil pump pressure reducing valve - 700-800 (7.0-9.0);
  • - differential valve - 490-520 (4.9-5.2);
  • - oil filter bypass valve - 200-250 (2.0-2.5)

Fuel supply system - split type

High pressure fuel pump (high pressure fuel pump) with regulator and fuel priming pump

Eight-section, plunger, spool-type plungers:

  • - plunger diameter 10 mm, plunger stroke 11 mm - YaMZ-238BE, YaMZ-238DE;
  • - plunger diameter 12 mm, plunger stroke 14 mm - YaMZ-238BE2, YaMZ-238DE2

YAMZ-238DE2 engine

Engine type - four-stroke, compression-ignition, turbocharged

Number of cylinders - 8

Cylinder arrangement - V - figurative, camber angle 90º

Cylinder firing order - 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right-hand

Cylinder diameter - 130 mm

Piston stroke - 140 mm

Displacement - 14.86 l

Compression ratio - 16.5

Rated power 243 (330) kW (hp)

Crankshaft speed at rated power 2100+50/-20 min -1

Maximum torque - 1274 (130) Nm (kgcm)

Rate at maximum torque - 1100-1300 min -1

Idle speed:

  • - maximum, no more than 2340 min -1
  • - minimum 650-700 min -1

Specific fuel consumption by speed characteristic, g/kWh (g/hp.h):

  • -minimum 195 (143);
  • - at rated power 230 (169)

Specific Oil consumption for waste in % of fuel consumption, no more than 0.2

Method of mixture formation - direct injection

Combustion chamber - undivided type in piston

Camshaft - one for both gear-driven cylinder banks

Valve timing:

Inlet valves

  • - opening, deg before TDC 21.5
  • - closing, deg after BDC 31.5

Exhaust valves

  • - opening, deg to HMT 63
  • - closing, deg after TDC 29.5

Number of valves per cylinder - one intake and one exhaust

Thermal valve clearances on a cold engine 0.25 - 0.30 mm

Lubrication system

Mixed, with oil cooling in a liquid-oil heat exchanger:

- bearings of the crankshaft, camshaft, pushers, rocker axles, spherical surfaces of pusher rods, high pressure fuel pump, turbocharger are lubricated under pressure.

The rest of the rubbing surfaces are lubricated by splashing.

Oil pump gear type, single section

Oil pressure on a warm engine in the block line, kPa (kgf/cm 2):

  • - at rated speed - 400-700 (4-7);
  • - at minimum speed, not less than - 80 (0.8)

Oil filters - full-flow cleaning filter with filter element and centrifugal cleaning filter

Oil cooling system with liquid-oil heat exchanger, which is mounted on the engine block on the left

Oil pressure for opening lubrication system valves, kPa (kgf/cm 2):

  • - oil pump pressure reducing valve - 700-800 (7.0-9.0);
  • - differential valve - 490-520 (4.9-5.2);
  • - oil filter bypass valve - 200-250 (2.0-2.5)

Fuel supply system - split type

High pressure fuel pump (high pressure fuel pump) with regulator and fuel priming pump

Eight-section, plunger, spool-type plungers:

  • - plunger diameter 10 mm, plunger stroke 11 mm - YaMZ-238BE, YaMZ-238DE;
  • - plunger diameter 12 mm, plunger stroke 14 mm - YaMZ-238BE2, YaMZ-238DE2

Injection pump model

  • 807.1111005-50(238BE-2);
  • 807.1111006-50(238BU-1);
  • 806.1111005-50(238DE-2);
  • 806.1111006-50(238DE-1,-5,-10,-11;
  • 173.1111005-30(238DE2,-1,-3,-5,-8,-11);
  • 173.1111006-30(238DE2-2,-6)

The order of operation of the fuel pump sections is 1-3-6-2-4-5-7-8

Regulator of speed - Centrifugal, all-mode

Fuel priming pump - Piston with manual fuel pump

Nozzles - Closed type with multi-hole nozzles:

  • - 261.1112010-11 on YaMZ-238BE, YaMZ-238DE engines;
  • - 267.1112010-02 or 204.1112010-50.01 on YaMZ-238BE2, YaMZ-238DE2 engines with common cylinder heads;
  • - 51.1112010-01 on YaMZ-238DE2 engines with individual heads

Injector injection start pressure, MPa (kgf/cm 2)

  • 20.6+0.8 (210+8) - 261.1112010-11
  • 26.5+0.8 (270+8) - 267.1112010-02 and 26.5+1.2 (270+12) - 204.1112010-50.01
  • 26.5+1.2 (270+12) - 51.1112010-01

Setting fuel injection advance angle - Set according to the marks on the flywheel and injection pump housing and is:

  • 13º±1 - on YaMZ-238BE, YaMZ-238DE engines;
  • 6º±1 - on YaMZ-238BE2, YaMZ-238DE2 engines with common heads;
  • 8º±1 - on YaMZ-238DE2 engines with individual heads

Fuel filters:

- coarse cleaning - With a replaceable element (YaMZ-238BE, DE), a sump (YaMZ-238BE2, DE2).

With replaceable filter element.

- fine cleaning

The bypass valve-jet is located on the cover.

Jet valve opening pressure 20-40 (0.2-0.4) kPa (kgf/cm 2)

Supercharge system - Gas turbine, one turbocharger, radial centripetal turbine and centrifugal compressor

Turbocharger (TKR) - Model 122 or TKR 100*

Boost pressure (excessive) at nominal operation, kPa (kgf/cm 2):

  • - YaMZ-238BE, YaMZ-238BE2 - 95 (0.95);
  • - YaMZ-238DE, YaMZ-238DE2 - 110 (1.10)

* - turbocharger similar in design to TKR model 122

new

After disassembling, thoroughly rinse all gearbox parts in kerosene, blow with compressed air and inspect

Possible pump malfunctions may include: leakage of the diaphragm and valves, decreased elasticity or breakage of the diaphragm spring, wear of pump drive parts