Quote:
The problem is more likely to be in the thermostatic fan control, in short, a sensor failure. Whilst it's difficult to stop this from happening, there is one thing you can do to guard against it recurring, namely fit a manual override switch in parallel with the thermo switch. Then if the thermo switch fails you can still keep the motor cool and a crisis is averted.
Of course, once you have a redundancy in the system, the thermo switch will work faultlessy for many years! I call it outwitting Murphy's law!
There is another possibility and that is that sufficient coolant was lost that the thermo switch was uncovered and therefore didn't engage the fan which made the engine hotter and more coolant was lost and so on, a vicious spiral! But I don't have enough info to confirm this as even a possibility!
Steve
Steve,
You're correct. All things are pointing towards the fan control switch & sensor as being the culprit.
I replaced the relay with a new one, got the car up past normal operating temp and it made no difference. I also noted that there was no coolant leak at any stage, even when sitting afterwards.
I tested the fan with direct power and its OK.
Luckily, I found locally and bought a new Davies Craig sensor/switch identical to what's in the car now and will install it this afternoon after it cools down.
After this scare, I will most definitely fit a manual override switch, as you suggest.
Thanks for answering.
Cheers,
Rob
EDIT: An update. It was the sensor/switch causing the greif. A new one has been installed, adjusted and now the thing is working just as it should.
Rob