Checking and topping up the coolant
Caution! Do not open the radiator cap if the temperature in the system is above 90°C. After cooling down for a while, open the cap slowly, releasing the pressure in small doses.
1. Unscrew and remove the radiator cap 1 (see figure 1.12).
2. Check the coolant level and top up if necessary if the coolant temperature does not exceed 50°C. The coolant level is determined by the marks on the radiator filler neck (arrow) (see figure 1.12). Before adding fluid, check its anti-corrosion properties. To do this, drain some liquid through the radiator drain cock.
3. If the anti-corrosion ability is low, it is necessary to replace the coolant.
4. Adjust the liquid level.
5. Install the radiator cap.
Figure 1.12. Unscrew and remove the radiator cap (1).
Replacing the coolant
6. Check the system for leaks.
7. Unscrew and remove the radiator cap 1 (see figure 1.12).
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8. Open the heating system control valve.
9. Drain the coolant from the system through the radiator drain cock 2 (if necessary, you can use a hose) (see figure 1.13 a, b).
Table 1.1. Volume of engine cooling systems.
10. Drain the coolant from the system through the drain plug or engine screw plug.
11. Check the cooling system for contamination. If the cooling system is very dirty, flush it.
12. Close all drain plugs and taps.
13. Fill in the amount of coolant specified in Table 1.1 (according to engine number).
14. Start the engine, let it run for about 1 minute and check for leaks in the cooling system.
15. Turn off the engine and check the fluid level, top up if necessary.
16. Install the radiator filler cap.
Figure 1.13a. Drain plug on engines 111 and 611.
Figure 1.13b. Drain plug on engine 601.