thermostat gasket needed?

[98gpking]

i got my new thermostat in and the new O-ring seal.. but no one ever told me anything about the gasket connecting the thermostat housing to the block. when i removed it to get to the thermostat it broke in half so i scrapped it all off and obviously cleaned it well and put the new tstat in and bolted her back shut. it dosent leak now but but thats not to say that it never will. do you think its 100% necesary for that gasket to be there or do you think the 0-ring will do the job.

[BNaylor]

Both '97 and '98 GPs normally require the gasket. See link below:

http://www.pfyc.com/supportfiles/tstat/tstat.htm


BTW - You might want to delete the other post on this subject which appears to be the same. For some reason you have a double post.

[jimmyv-21]

i would say that if there was a gasket there, then it is probebly there for a reason. all the tstats i have done have required the gasket, and just to be safe i also use the atf sealant. mechanics will use the gasket at a minimum, but i have also seen some use only the sealant. you have to remember that the coolant is a liquid, and liquid has a funny way of finding/ making leaks or holes. it may not be leaking now, but that is not to say after a few miles/ races at the lights that it wont. better safe than sorry. just my 2 cents...

[gtp2k2]

ahh my post didnt get on here.. yes you'll need 2 gaskets.. the o ring around the tstat and the t stat housing gasket.. dont mess with RTV, spend the extra 2 bucks for the right part

[jimmyv-21]

as stated before, mechanics will OFTEN use only the sealant. it can be used on many applications such as the valve cover and tstat housing. while i personally would use it only in addition to the gasket, i know from using it myself and from a certified gm mechanic that it can be used by itself and give you an equal or better seal as the gasket. all paper gaskets are prone to leak over time and mileage, so why not give yourself the extra protection?

[wlkjr]

I just changed mine out yesterday and used a Felpro 35595 gasket. It has a red silicone ring around the hole. It was 2.99 at OReilly's.

[richtazz]

Most people don't know how much RTV to use, and if you use too much, the excess can get stuck in an engine passage and cause all sorts of fun issues. The only places I use any RTV/gasket adhesive is on intake end seals (RTV) and to hold hard to reach/ungainly large gaskets in place (adhesive). If you don't let the RTV "skin" before assembly, it all gets squeezed out anyway, so its a waste of time and money. Us equality gaskets and follow assembly proceedures, and you won't need to use RTV, except as noted above or when a gasket no longer is available. Just my 2 cents.