Quote Originally Posted by Coger View Post
I have been told by different cooling guys, to only use factory thermostats. I notice a hole in the flange, I had an apprentice drill a hole (old practise from the 70s) in a factory thermostat caused the motor to run cold as there was coolant continually flowing thru. Replaced thermostat solved all issues. This is on a td42.
Yeah, I agree. Factory thermostat is always better. I went for an aftermarket one 'cos of budget constraints.
Drilling holes on a standard thermostat is bad idea, even though we do it sometime to remedy overheating issues.
It's always better to find out the actual cause of the overheating and fix that.
For example modifying the thermostat to deal with an overheating issue that is caused by the viscous fan or radiator is a
bad move IMO.