Going to try installing a new thermostat in a friends car thats overheating. The "ECT" switch on the side of the thermostat... what does it do? Does it need to be replaced as well with the thermostat? Does the ECT activate the fan to turn on and off? Or is that switch located on the side of the head? Anyone have pics?

 

the plug on the thermostat housing is the fan switch

 

Thanks Steve. Do they usually get :killed: when a thermostat dies? This cars coolant is BOILING out of the radiator... and steaming into the resv. coolant tank.. headgaskets good though. No fan operation either.

 

the fan wont come on because the thermostat isnt opening and no hot water is getting to the switch telling it to turn on

 

So I should probably not order a new switch right away... until I try replacing the thermo first, eh?

 

never seen one go bad, short of someone crushing the plug.

if the lower radiator hose isnt getting hot, the thermo isnt opening which is why the
fan isnt coming on.

 

Ut oh.. both hoses are hot though. The top hose from head to radiator feels DRY inside at all times... this is a pain in the ***. Coolant levels are fine before the cars driven.. then by the time I bring it back into the garage, it has sucked the resivoir dry, and is steaming like crazy from the radiator boiling and blowing steam into it... Any thoughts?

 

head gasket

 

I thought head gasket too... but I took the radiator cap off when the car was cold... started it up, and revved it up 5-6 times and the coolant level did not budge or bubble up one bit... could it *still* be the gasket?

 

do that when the motor is warmed up.
replace the thermostat anyway, its easy and could still be the problem

 

Awe ****... I warmed it up and blipped the throttle, and I get some splashing in sync with the revving. headgaskets toast eh? This GS-R motor is DRAG 3 equipped at only 5-6psi of boost... but he ran the allmighty JRSC at 8-9psi for a while first.

 

there you go