The 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 / m3, as well as for vehicle movement 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.

Diesel YaMZ-238

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

Maintenance work is preventive, so it must be done within the stipulated 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

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

Oil-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

YaMZ-238 dimensions

Main parameters and characteristics

Powertrain Models

YaMZ-238BE

YaMZ-238BE2

YaMZ-238DE

YaMZ-238DE2

engine's type

Four-stroke, compression-ignition, turbocharged

Number of cylinders

8

Cylinder arrangement

V-shaped, camber angle 90º

The order of operation of the cylinders

1-5-4-2-6-3-7-8

Direction of rotation of the crankshaft

Right

Cylinder diameter, mm

130

Piston stroke, mm

140

Working volume, l

14,86

Compression ratio

16,5

Rated power, kW (hp)

220 (300)

243 (330)

Speed

at rated power, min-1

2000 +50/-20

2100+50/-20

Maximum torque, N m (kgf m)

1180 (120)

1274 (130)

1225 (125)

1274 (130)

Rotational speed at maximum torque, min-1

1200 - 1400

1100 - 1300

1200 - 1400

1100 - 1300

Idling speed, min-1:

- maximum, no more

- minimum

 

2175

600±50

 

2340

650…700

 

2275

600±50

 

2340

650…700

Specific fuel consumption

according to the speed characteristic, g / kW h (g / hp h):

- minimum

- at rated power

 

206,7 (152)

227 (167)

 

195 (143)

223 (164)

 

206,7 (152)

227 (167)

 

195 (143)

230 (169)

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

0,5

0,2

0,5

0,2

Mixing method

direct injection

The combustion chamber

Undivided type in the piston

Camshaft

One for both rows of gear driven cylinders

Valve timing:

intake valves

- opening, hail. up to TDC

- closing, hail. after BMT

exhaust valves

- opening, hail. to BDC

- closing, hail. after TDC

 

 

20

40

 

66

20

 

 

21,5

31,5

 

63

29,5

 

 

20

40

 

66

20

 

 

21,5

31,5

 

63

29,5

Number of valves per cylinder

One intake and one exhaust

Thermal valve clearances on a cold engine, mm

0,25 - 0,30

Lubrication system

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

- bearings of the crankshaft, camshaft are lubricated under pressure,

pushers, rocker axles, spherical surfaces of pusher rods,

high pressure fuel pump, turbocharger.

The rest of the rubbing surfaces are lubricated by spraying.

Oil pump gear type, single section

Oil pressure on a warm engine in the block line, kPa (kgf/cm2):

- at rated speed

- at minimum speed, not less than

 

 400 - 700 (4 - 7)

80 (0,8)

Oil filters

Two: 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 on the left

Oil pressure for opening lubrication system valves, kPa (kgf/cm2):

- oil pump pressure reducing valve

- differential valve

- oil filter bypass valve

 

 700 - 800 (7,0 – 8,0)

490 - 520 (4,9 - 5,2)

200 - 250 (2,0 - 2,5)

Fuel supply system

split type

High pressure fuel pump (TNVD) with a regulator

and fuel 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

Main parameters and characteristics

YaMZ-238BE

YaMZ-238BE2

YaMZ-238DE

YaMZ-238DE2

High pressure fuel pump model

807.1111005-50

(YaMZ-238BE2)

807.1111006-50

(YaMZ-238BE-1)

173.1111006-20

806.1111005-50

(YaMZ-238DE2)

806.1111006-50

(YaMZ-238DE-1,-5,-10,-11)

173.1111005-30

(YaMZ-238DE2,-1,-3,-5,-8,-11)

173.1111006-30

(YaMZ-238DE2-2,-6)

The order of the sections

fuel pump

1-3-6-2-4-5-7-8

Speed controller

Centrifugal, all-mode

Fuel 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 engines,

YaMZ-238DE2 with common cylinder heads;

- 51.1112010-01 on YaMZ-238DE2 engines with individual heads

Injector injection start pressure,

MPa (kgf/cm2)


 

20,6+0,8 (210+8) - 261.1112010-11

26,5+0,8 (270+8) - 267.1112010-02 и 26,5+1,2 (270+12) - 204.1112010-50.01

26,5+1,2 (270+12) - 51.1112010-01

Adjustable advance angle

fuel injection


 

It is installed according to the marks on the flywheel and the 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

fine cleaning

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

With replaceable filter element.

On the cover is a bypass valve-jet.

Valve-jet opening pressure 20…40 (0.2…0.4) kPa (kgf/cm2)

Pressurization system

Gas turbine, one turbocharger,

with radial centripetal turbine

and centrifugal compressor

Turbocharger (TKR)

Model 122 or TKR 100*

Boost pressure (overpressure)

at nominal operation, kPa (kgf/cm2)

95 (0,95)

110 (1,10)

* - turbocharger similar in design to TKR model 122