You will need: an 8 mm spanner, a 13 mm open-end spanner, a screwdriver, coolant, and a clean cloth.
Warnings: Change the coolant only when the engine is cold.
Coolant is toxic, so be careful when handling it.
When starting the engine, the expansion tank cap must be closed.
1. Place the car on a flat, horizontal surface. If the surface is inclined, position the car so that its front part is higher than the rear.
2. Disconnect the wire from the "-" terminal of the battery.
3. Open the heater valve by moving the valve control lever to the right until it stops.
4. To access drain plug 1 on the engine block, remove ignition module 2 together with the bracket (see "Removal and installation the ignition module").
5. Unscrew the expansion tank cap.
6. Place a container under the engine and unscrew the drain plug on the cylinder block.
After draining the coolant, wipe any traces of it off the cylinder block.
7. Place a container under the radiator, unscrew the drain plug on the radiator and wait until the coolant has completely drained from the system.
8. Tighten the plugs on the cylinder block and radiator.
9. To prevent an air lock from forming when filling the cooling system with liquid, loosen the clamp and disconnect the coolant supply hose from the throttle heating nipple. Pour liquid into the expansion tank until it appears from the hose.
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Place the hose back in place.
10. Completely fill the engine cooling system by pouring coolant into the expansion tank until its level reaches the "MAX" mark. Screw in the expansion tank cap.
Warning! Tighten the expansion tank cap tightly.
The expansion tank is under pressure when the engine is running, so coolant may leak from under a loosely tightened cap or the cap may come off.
11. Install the ignition module in the reverse order of removal.
12. Connect the wire to the "-" terminal of the battery.
13. Start the engine and let it warm up to operating temperature (before turning on the fan).
After this, stop the engine, check the coolant level and, if necessary, top up to the "MAX" mark on the expansion tank.
Warning! When the engine is running, monitor the coolant temperature on the indicator. If the arrow has moved to the red zone and the fan has not turned on, turn on the heater and check what air is coming through it.
If heated air flows through the heater, the fan is most likely faulty; if it is cold, it means that an air lock has formed in the engine cooling system.
After this, stop the engine. To remove the air lock, let the engine cool down and unscrew the expansion tank cap (be careful: if the engine has not cooled down completely, the coolant may splash out of the reservoir).
Disconnect the coolant supply hose from the throttle heating fitting and fill the expansion tank with liquid to the required level.