Bah! Replaced the thermostat a few weeks ago and noticed the other day that there is a small pool forming on the intake from the thermostat housing. What did I most likley do wrong? Didn't use enough gasket sealer? Or didn't wait long enough before filling the system with coolant?

Thanks for the help


Robert

 

Did you tighten the 2 bolts up enough. Just because I say that, doesnt mean you didnt so dont go and wrench on them again if there tight, its only aluminum there threading into and you can strip the threads out. Also, did you clean off the old gasket from the neck and intake? I would start over and make sure both surfaces are cleaned and run a 1/8" bead of sealer around the gasket. Tighten the bolts and top off coolant. Do not go and fire the car up. wait a little while for the sealer to set( this will depend on what gasket sealer you use). Also, make sure the hose clamp is tight too if you removed it

 

yea, make sure your surfaces are clean from any old gasket material. i just changed mine last week and the way i did it was to put a thin film on both sides of the gasket and then put the waterneck on, tighten it down good, don't wrench it on as already mentioned. i was able to let my car sit overnight since i didn't need it, so i got a good seal. i topped it off with 50/50 next day. got a great seal on it...

KAM

 

Yup, cleaned everything up nice and tightened the bolts up but was careful because as you say it is aluminum. However, I'm now thinking that it is because I filled the system and started the car up too soon. I'll leave it sitting over night this time. I'll report back when it's done.

Thanks again


Robert

 

do all the stuff listed above. But also make sure the the themrostat seated right. That could leave a gap between the intake and housing. Also maybe look for a crack in the house.

 

make sure you put the thermostat in BEFORE you put the gasket and water neck on, if you reverse the two you are sure to have a leak.

 

There sure are a lot of gasket maker followers. I've never used any type of sealant on the thermo housing and have yet to have a leak.
I just clean things off really well and torque down the bolts with the new gasket.

 

I was the same way with gasket sealer on the thermostart housing but *** knows what the gaskets are made out of these days. Things like that I just get at the parts store and then lay a little sealer on 1 side of the gasket to hold it in place while I put in back on.

 

not sure why you used gasket sealer. if you buy a gasket, that's the point of it. it's job is to seal it. don't use any sealer on the theromstat gasket, clean the surface and just put it together. there is a reason it didn't come from the factory with it there, it doesn't need it.

 

did you replace the thermostat housing? because some of the cheap one size fits all housings you get at parts stores are real trash. I had one on my 89 rs, and no matter how much sealant or how much i tightened it; it just would not seal well.

So the moral is to only get gm thermostat housings and gaskets.

 

You probably used the aftermarket gasket. The AC-Delco replacement is a "printoseal" type, it has a rubber gasket impregnated into the material. It's a once and done.