Warning! Do not allow antifreeze to come into contact with your skin or painted surfaces of your vehicle. If it does come into contact with your skin, rinse immediately with plenty of water. Antifreeze is extremely toxic and can be fatal if ingested. Do not leave antifreeze in an open container or spilled on the floor; its sweet smell can easily attract children or pets. Check your local regulations for disposal of used antifreeze. Many areas have special collection centers.
The cooling system should be drained, flushed and refilled regularly. This procedure is performed to maintain the quality of the cooling mixture and prevent corrosion, which reduces the efficiency of the cooling system and can cause engine failure. During maintenance of the cooling system, the condition of all hoses and the radiator cap should also be checked and defective components replaced if necessary.
Dehumidification
1. Unscrew the radiator cap. This can only be done on a cold engine. If the engine is hot, unscrew the cap until the first click (with a rag) and wait for the steam to escape.
2. If the system needs to maintain frost resistance, some measures must be taken. During some work on the cooling system, the coolant does not need to be drained completely. Thus, when removing the upper hose or thermostat, it is enough to drain the coolant to the level of the corresponding element.
3. Set the heater control to the "heat" position.
4. Disconnect the lower water hose and drain the fluid. There is a plug inserted into the side of the cylinder block (next to the oil dipstick), which must be unscrewed to release the cylinder block from the coolant. A little higher is the air bleed bolt. Open this bolt. On an injection engine, also open the air bleed bolt in the heater hose.
5. If the coolant is drained to clean the system, remove and drain the expansion tank. Clean the tank and reinstall it.
6. After draining, reconnect the water hose and screw the drain plug into the cylinder block.
Flushing
1. After the system has completely drained, flush the radiator with clean water from a garden hose until clean water runs out of the drain hole or bottom hose. If the radiator is badly rusted, damaged or leaking, it should be removed (see Chapter Cooling and heating systems) and send it to a repair shop to a radiator specialist.
2. The flush described above will remove various deposits from the radiator, but will not remove rust and scale from the engine surfaces and coolant pipes. All of this can be removed with a chemical cleaner. Follow the instructions of the cleaner manufacturer to perform this procedure. Before flushing the engine, open the drain plug of the cylinder block.
3. On suitably equipped models, remove the overflow hose from the expansion tank. Drain the tank, rinse it with clean water and reconnect the hose.
Filling
1. Check again that the drain holes are closed.
2. Prepare antifreeze coolant. The content of 30% antifreeze concentrate provides frost resistance up to -15°C; 50% to -35°C.
3. Slowly pour coolant through the radiator opening and fill the expansion tank as well. Tighten the bleed screw when coolant starts to flow out of the openings. Coolant should be visible in the filler hole.
4. Screw on the radiator cap.
5. Run the engine until operating temperature is reached (the fan should turn on) and then cool the engine again. After a few hours, check the coolant level again. Depending on the installed engine, the system volume differs, its value is indicated in Specifications at the beginning of the Chapter. 0.7 liters should be poured into the expansion tank.