Help Diagnosing Dead Thermostat

[wilch]

Hey guys,

Here's the jist:

R32 GTST RB20det

Appears to be overheating. Thermofan turns on and can hear it above 3000rpm sometimes....And it's happening more frequently as the weather is getting hotter.

Only use to do it sometimes.

Now does it all the time.

Anyway, I just took it for a drive to warm everything up and to test the new fuel pump. Came back home and opened the bonnet.

Touched the top radiator hose, was hot to the touch.

Touched the bottom radiator hose near the block, and it was cold to the touch.

Now this bottom hose is where the thermostat is.

Am I right in thinking that because the top one is hot, and the bottom one (where the thermostat is) is cold, that the thermostat is broken in the closed position?

Cheers,

wil..

[Risking]

Thermostate is jammed closed.

Remove it throw it into boiling water to see if it opens then replace it cause it won't open.

[wilch]

Cheers, thanks dude.

[GoldZilla]

Thermostate is jammed closed.

Remove it throw it into boiling water to see if it opens then replace it cause it won't open.

Oh yeah, forgot about that testing trick - my old man used to do that!

[gtrchick]

yeah but it has to open at a certain temp range...

[mad082]

the bottom hose (cold one) is where the water goes into the motor. the top (hot) hose is where the water comes out of the head. so the top hose should be hotter than the bottom one. that is why that is where to temp sensor is. so that it reads the hottest temp the water gets to.

do you have a fmic? if you do then that won't be helping as it slows a lot of air going through the radiator.

[wilch]

The 32 is stock.

Hmmm...I was lead to believe that the bottom hose is where the thermostat is. It's cold, and it shouldn't be when the top one is hot.

(photo of upside down engine courtesy of mr32)

[Doctor 30]

I have the same problem but my thermostat opens in boiling water. I heard that if if doesn't open on boiling water it is definitely stuffed. But if it does open it doesn't necessarily mean it is good because it is a totally different enviroment under pressure.

Can anyone confirm if I am right or wrong in thinking this?

[Duncan]

isn't a thermostate $20 at your local repco? just grab one and a gasket and change it

if you really want to check the boiling water trick you need a temp gauge in it as well make sure it opens at the right temp 76o for GTR not sure if gtst is the same

[mad082]

the other problem is that it may open in boiling water, but it may not open all the way when in the car.