Thermostat Replacement

[GTPer]

I want to put a 180 thermostat on my GTP. But Im not sure how to drain the radiator on this engine. If someone can tell me where the drain plug is located or just how I can drain the radiator that would help a lot. thanks. I saw a little yellow plug but im not sure if that's it, it's kinda sideways.

[Imp558]

I had a 97 GP Radiator in mine for about a year.

 

Driver's side of radiator, on the back side of it. Of course you realize the PCM should be calibrated to correlate the fan temp to the new stat?

[GTPer]

Is it really necessary? I thought the fans really only mattered at idle when the car isn't moving. It should still cool right though right?

[The Guz]

Since you are stock just stick with the stock 195 t-stat. Also to change out the t-stat you really don't need to drain the radiator. I never have.

[GTPer]

Since you are stock just stick with the stock 195 t-stat. Also to change out the t-stat you really don't need to drain the radiator. I never have.

Really? How would you replace the thermostat on this engine without draining? Ill probably wait and do both the thermostat and a ZZP PCM at the same time.

[The Guz]

Yes. It's just two bolts that hold the housing. Remove those and the housing and you will have access to the t-stat. You will lose a very tiny amount of coolant when pulling the t-stat out.

[GTPer]

Yes. It's just two bolts that hold the housing. Remove those and the housing and you will have access to the t-stat. You will lose a very tiny amount of coolant when pulling the t-stat out.

You mean I'll lose coolant from that upper radiator hose right? So just hold something next to the hose to catch while I pull the housing off? So if the engine is completely cold I assume there would be little to no coolant in that upper house right?

[George]

If the coolant in the radiator is higher than the housing the coolant will run out until the coolant gets down to the level of the housing. My radiator drain is stuck so I stick a 1/4" hose down the radiator neck and syphon off the coolant in to a bottle. Mine is a '94 LQ1 and I can only drain out a gallon or so, but is plenty.

[The Guz]

You mean I'll lose coolant from that upper radiator hose right? So just hold something next to the hose to catch while I pull the housing off? So if the engine is completely cold I assume there would be little to no coolant in that upper house right?

 

This should help. Two good videos. I have never had to drain any coolant. Although the car sits overnight before I replace it.

 

 

[GTPer]

This is kinda unrelated but Ill post here anyway. So I went to 2 different mechanics and they say my intake manifold gaaskets need replaced. It gradually leaks oil but I don't think it leaks coolant. And you can see a lot of oil around under the supercharger and lower manifold. My question is 350 to fix it reasonable? And I thought since it had 186k miles on it that it would have had them replaced already but I guess not. I thought it was only a common problem on lower mileage engines.