Is sealant really necessary on a thermostat gasket?

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dibbons

dibbons

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Going to replace the thermostat on a 3.9L (318 clone) Dakota and had to remove the A/C compressor to get at it. The thermostat gasket is one pretty thick piece of paper and it seems it would be more than adequate to fill any voids (large or small) in the intake manifold or thermostat housing itself. Will it work out just fine without gooping it all up with additional sealant? Thank you.
 
trust me i'm no mechanic, buy I always clean the surface hopefully totally good, but I always smear thin coat on there for good measure. What possibly does it hurt??????

but then again, I' m not a purist, perfectionist, and sometimes i'm just plain messy!
 
Like Barbee says, I always smear a thin coat of RTV that can't really be seen. If some does squeeze out, I peel off the excess after it dries.
 
I never use it, but as was mentioned what could it hurt. Who cares what it looks like on the outside, just make sure it doesn't end up on the inside.
 
Buy a 2nd gasket and do it without rtv. If it leaks redo it with sealant. If I was to rtv it would NOT be on the gasket side, but on the side that has the "recess" for the t-stat
 
I like using Permatex #3 (aviation sealer). It cleans off easy with solvent (unlike some other gasket sealants).
 
I would use a light coat of rtv on the gasket, do you really want to remove the ac compressor again?
 
If the surfaces are flat, I have good success dry. More so than warped and RTV.But if the housing with the recess has been straightened one too many a time, such that the recess is no longer deep enough, nothing will seal it. The recess would need to be re-machined( die-grinder). And those late style, thin metal housings, can be a PITA. The coolant likes to work its way over to the bolts and come up the threads. So that would be a good place to put the RTV; on the threads and under the bolt-head.Do your best to prove that housing is flat, especially the stamped steel one.
 
no you dont need that stuff there unless your the nervous type .
 
Aaron65 said:
I like using Permatex #3 (aviation sealer). It cleans off easy with solvent (unlike some other gasket sealants).
Click to expand...

Anymore, I'm a fan of the old school Permatex sealers too - #2 or #3. In this case, I'd opt for a little insurance over a dry gasket.
 
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