OK, a quick summary of the events leading up to the apparent problem with my
cars cooling system.
Noticed there was a leak on the cooling system the other week, turned out to
be a crack in the thermostat housing. So replaced the housing, seals and
Took it for a test spin after refilling, noticed both cooling fans were
coming on, despite the fact the bottom radiator hose coming from the
thermostat was still cold and the temp gauge was still "normal".
Assumed it was an airlock, so stopped, gently turned the filler cap on the
expansion tank to release the pressure. There was a lot of bubbling, which I
thought meant it was just air pockets escaping. After I restarted all seemed
However, I've noticed that the cooling fans keep coming on when I'm driving
around, even though the temp gauge says the temperature is normal and the
bottom radiator hose is cold. When I stop and release the pressure on the
expansion tank, there's a lot of bubbling water coming from the hose that
feeds back into the tank from the top of the engine block and the fans stop
for a while.
Tried flushing the radiator through to see if there was a problem there,
flushed through fine.
If I didn't know better I'd say it was a combination of faulty thermostat
and temperature gauge not giving the correct reading.
Any other suggestions what the problem might be before having to take the
thermostat back out for testing? Don't really want to do that if I don't
have to as its an absolute swine to get to, being sandwiched between the
alternator and air-con cooling pump, meaning a major strip down. Wouldn't
have thought it would have been the thermostat with it being brand new, but
don;t know what else it could be? Engine is supposed to run at 82 degrees
and bought the correct stat.
The car is a V reg Ford focus, 1.6 petrol, with a zetec engine. UK model.
Any suggestions gratefully appreciated.
Simon (Dark Angel)
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