I decided to upgrade my fan override to the one mentioned in blatchat archives and old Low Flying. it uses a relay so is better than the simple non relay circuit had already..
My query is this, the circuit is designed to run direct off the battery so that the fan continues to run when stopped, evidently to save the head gasket a bit.
Now. I see that the fan would continue to run if the temp switch is active BUT:
a) As only the fan would continue, water pump would not continue, how long would the fan run on for on average, as I'm worried the battery will drain.
b) Is it really worth worrying about?