The figure shows the installation locations of the parts and their designations according to the spare parts catalog

We look at the figure and the table shows the decoding of the part.

The main thermostat valve begins to open at a coolant temperature of 84-87 ° C.

At a temperature of 94 ° C, it is already fully open.

When the main valve is closed, the liquid in the engine cooling system circulates, bypassing the radiator, through the open additional thermostat valve inside the engine cooling jacket.

When the main valve is fully open, the additional valve is closed and all the liquid passes through the cooling radiator.

fig. 1. D-245 engine thermostat parts according to the catalog

D-245 engine thermostat parts according to the catalog

  • - 245-1306021 Housing   
  • - 245-1306023 Gasket
  • - 245-1306027 Fitting  
  • - 245-1306028-G Cover 
  • - 245-1306030-04 Thermostat assembly
  • - 50-1306026 Gasket
  • - 50-1306028-B2 Hose
  • - 50-1401067 Washer
  • - KG3/8"A12.019 Plug
  • - M8-6gx25.88.35.019 Bolt
  • - M8-7gx95.88.35.019 Bolt
  • - TS107-1306100-04 Thermostat
  • - HCP10.019(HS-26.019) Clamp

The body heater is connected in parallel with the radiator, and the thermostat does not disconnect it from the engine.

Therefore, when warming up the engine, do not open the air intake flap and turn on the heater electric motor.

The thermostat automatically maintains the required temperature of the coolant in the engine, turning off and on the circulation of liquid through radiator.

In cold weather, especially at low engine loads, almost all heat is removed as a result of cold air blowing over the engine, and the coolant does not circulate through the radiator.

To maintain the optimal engine temperature at negative ambient temperatures, it is necessary to cover the radiator lining with a cover.

To check or replace the thermostat, you need to:

Drain about 5 liters of liquid from the radiator of the cooling system into a pre-prepared container.

Loosen the hose clamp.

Disconnect the liquid supply hose.

Replacing the thermostat

Unscrew the four bolts securing the top cover of the thermostat housing.

Remove the thermostat from the housing.

Assembly is carried out in the reverse order.

The thermostat must be cleaned of scale in boiling 8-10% alkaline solution for 15-20 minutes, and then rinsed with clean water.

The temperature at the moment of the beginning of the opening of the thermostat valve, placed in gradually heated water, should be 84-87 ° C, and at the moment of the full opening of the valve 91-95 ° C, the lifting height of the fully open valve is not less than 8.5 mm.

The thermostat valve in the closed position should fit tightly to the seat; the permissible gap between the valve and the seat is 0.1 mm.

The valve displacement relative to the neck is allowed no more than 0.5 mm.