Note: Recommended frequency: every 50,000 km or 24 months.
Caution! Avoid contact with coolant on clothing or vehicle paintwork. Otherwise, rinse the surface with plenty of water. Collect and dispose of drained coolant.
Replace the coolant at the recommended intervals and after any work on the cooling system components that involves draining the coolant. If the cylinder head, head gasket, radiator, or oil heat exchanger were replaced during repair, fill the cooling system with fresh coolant. This is due to the fact that the anti-corrosion additive in the coolant settles during engine operation and creates anti-corrosion protection. In used coolant, the anti-corrosion additives are not active enough to form a protective layer on newly installed parts.
Draining the coolant
Drain the coolant on a cold engine.
Remove the radiator cap.
Figure 2.36. Location of the radiator coolant drain pipe
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Place a container to collect the coolant under the radiator drain pipe. Attach a 9.5mm ID hose to the drain outlet to direct the coolant into the container. On some models the hose is installed at the time of vehicle production. Open the drain plug and drain the coolant from the radiator (figure 2.36).
Figure 2.37. Location of the tap and coolant drain pipe from the cylinder block on vehicles produced since 2001
Place a container under the coolant drain pipe from the cylinder block (figure 2.37). Attach a 9.5mm ID hose to the drain outlet to direct the coolant into the container. Using a wrench, open the tap and drain the coolant from the cylinder block.
Check the condition of the radiator and heater hoses, as well as the reliability of their fastening with clamps. Replace damaged hoses and clamps.
Flushing
After draining the coolant, remove the thermostat and reinstall the thermostat housing. This will allow you to flush the cooling system faster.
Close the radiator drain plug. Set the heater control knob to the maximum heat position so that the radiator and heater hoses are also flushed.
Figure 2.38. Flushing the cooling system: 1 – garden hose; 2 – upper radiator hose; 3 – radiator
Disconnect the upper radiator hose from the radiator, then insert a garden hose into the radiator hose and flush the system with clean water until clear water comes out of the upper radiator hose (figure 2.38).
If the radiator is seriously contaminated, remove the radiator and wash it with a special agent, following the instructions for use.
Place a garden hose into the expansion tank and flush the system with clean water until clear water comes out of the top radiator hose.
Connect the upper radiator hose to the radiator.
Filling
Close the coolant drain plug from the radiator and the drain valve from the cylinder block. Reinstall the thermostat.
Set the heater control knob to the maximum heat position.
Slowly pour fresh coolant into the radiator until it appears from the radiator filler neck. Add coolant to the expansion tank up to the minimum mark.
Close the radiator cap. Start the engine and warm it up until the thermostat opens, at which point the coolant begins to flow through the radiator. The radiator and upper radiator hose will begin to heat up.
Turn off the engine and wait until it cools down. Add coolant until it appears from the radiator filler neck.
Squeeze the upper radiator hose several times to remove air from the cooling system and add coolant if necessary. Install the radiator cap.
Start the engine, warm it up to operating temperature and check the cooling system for leaks.