Driving across Europe, i noticed the car was using water. I drove slowly and got to the destination. Since then, the symptoms have been getting stranger.
- The water loss is caused by excess pressure in the system, no visible leaks.
- Sometimes the radiator works (gets hot) and the engine does not heat, sometimes the opposite happens. In this case I stop and wait for the engine to cool off so no damage has been done.
- Today on a stone cold engine we opened the water cap and the cooling circuit was still under a lot of pressure.
- The water pump is almost brand new.
- The condition of the thermostat is unknown.
I am not sure what I am looking at here. Any help much appreciated.
After much checking and testing, here is the new status:
I pulled the top hose off and found a small piece of instant gasket from the new water pump last year (I didn't know about this replacement until I took the thermostat out). I think this was blocking the pressure equalizing tube. The thermostat was fine, as was the thermoswitch on the radiator. I drained the circuit : no sludge, and I even ran water both ways through the radiator: it came out clean.
Now when i run it, the top hose seems rather hard, as if there was a lot of pressure in there. Is this normal? Obviously there should be pressure, but before there was less, although this could be that the circuit was filled without being burped. I have refilled it with good coolant, and burped it properly.