Flushing Cooling and Heating System
Component Notes And Information- Drain coolant.
- Remove coolant thermostat and install pressure-opened thermostat.
- Install flushing connection pipe (01) and connect tap water hose.
- Flush cooling system.
- Check cooling system for leaks.
NOTE: High coolant temperatures and low heating capacity may be caused, for example, by deposits of corrosion products in the radiator or in the heat exchanger. The deposits are recognizable as a jelly-like mass or, when the radiator is emptied and dry, from a gray layer on the radiator connection pipes. In this case, flush the cooling and heating system with water. If the cooling pipes of the radiator are already completely or partially clogged by deposits, the radiator must be replaced.
Procedure
1. Drain coolant.
2. Remove coolant thermostat and install pressure opened thermostat with seal.
3. Fit flushing connection pipe (01) together with connection hose (02) between radiator and coolant hose.
4. On a tap water hose (03) onto the flushing connection pipe (01).
5. Open cap of expansion reservoir.
6. Set heater to "warm".
7. On models fitted with circulation pump, switch on circulation pump.
To do this, switch on ignition and:
a) On models with automatic heater, set temperature selectors to "Max" position.
b) On models with air conditioning (automatic), press "Defrost" push-button.
8. On all models, open bleeder valve of auxiliary heater.
9. Run engine at about 2500 RPM and flush cooling and heating system for about 15 minutes with flowing water.
NOTE: The cooling system must always be completely filled during the flushing operation. Regulate the quantity fed in accordingly.
10. Drain the flushing water completely in the radiator and crankcase: tighten drain plugs (17 and 82). Replace seal (18).
11. Remove flushing connection pipe and connect coolant hose to the radiator.
12. Install normal coolant thermostat with new seal.
13. On models fitted with stationary heater, connect plastic hose to bleeder valve and open valve.
14. On all models, pour in fresh coolant.
15. Check cooling system for leaks.