Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 16 of 16 Posts

·
Registered
Joined
·
36 Posts
Discussion Starter · #1 ·
I had a crack in my old thermostat housing that was causing a pretty good leak so i had to replace it. I read on a previous thread to get a good seal on the new thermostat housing to use red high temp RTV on both sides of the new gasket before installing so i did the directions on the tube say let dry for 1hour and to fully cure 24hours do i need to let my jeep sit for a day before adding any fluids and letting the engine get warm?
 

·
Registered
Joined
·
1,044 Posts
1 hour add fluid, check for leak, 24 hours start it up, check for leak. ive never had rtv not leak after the first time. the cardboard gasket is good enough on its own.
 

·
Knows a couple things...
Joined
·
49,625 Posts
Personally, I would have not used any RTV on the thermostat housing at all. It doesn't take much to get a good seal there, today's gaskets do a good job at sealing the water pump, thermostat housing, etc. Heck I had a trail overheating emergency where I had to remove the thermostat housing & then put it back together using only a piece of cardboard from a MRE container box as the gasket. Even that makeshift cardboard gasket was completely leak free until I could get around to installing a new thermostat & a "real" gasket.
 

·
Knows a couple things...
Joined
·
49,625 Posts
you could use the cardboard box the thermostat came in to make a decent gasket.
Exactly. Which is not to say cardboard is the best material to use, it's just saying that it doesn't take much to seal the thermostat housing. RTV is not needed or recommended by the factory.
 

·
Registered
Joined
·
1,044 Posts
thats not to say I don't keep a tube with me all the time just in case, but its never my first, second, or even 3rd choice. I keep it for emergency only.
 

·
Registered
Joined
·
2,362 Posts
A skim of Indian Head shellac to hold the gasket in place while I get it bolted up is the closest I come to silicone. Hate the stuff, on the Jeep that is :)
 

·
Registered
Joined
·
3,136 Posts
I guess I'll answer the OP's question, since he already used RTV.
No need to wait. Just fill it and go. I've been using RTV on T-stat gaskets for 25 years, and have never had an issue.

And I don't mean a huge bead that squishes out everywhere. Just a nice, thin coat.
 

·
Registered
Joined
·
2,362 Posts
I guess I'll answer the OP's question, since he already used RTV.
No need to wait. Just fill it and go. I've been using RTV on T-stat gaskets for 25 years, and have never had an issue.

And I don't mean a huge bead that squishes out everywhere. Just a nice, thin coat.
1 hour add fluid, check for leak, 24 hours start it up, check for leak. ive never had rtv not leak after the first time. the cardboard gasket is good enough on its own.
Hmm
 

·
Registered
Joined
·
2 Posts
I'd agree with PatrickH as I've used the red high temp rtv on heavy duty diesel trucks/tractors and trailers for years from oil cooler covers, water pumps to wheel hub assemblies. In fact the cheaper gaskets they throw on m2 box trucks and freightliner Cascadia these days are going to fail within 5k miles and we'd replace them on new trucks with red high temp RTV pit an nice thin layer on the axle shift that goes into the hub assemblies bolt it up fill it and send it on the road never waited for it to "cure" and never once had an hub assembly come back leaking shit to will be good till the next timr you have to take that drive axle out after probably couple hundred thousand miles and inner seal or what not fails and when you open it back up its practically peal off easy asf slap another thin layer rtv 9n when sealing it back up lmfao always use high temp rtv imo some ppl say to use the black oil resistant but high temp has never failed me yet
 

·
Registered
Joined
·
2 Posts
Oh ya it also cures on exposure to moisture in air so any fluid will cure the rtv it also dries tack free in an hour anyways
 

·
Retired Moderator
Joined
·
102,504 Posts
Oh ya it also cures on exposure to moisture in air so any fluid will cure the rtv it also dries tack free in an hour anyways
Welcome to the Forum, from Cave Creek AZ.
 
  • Like
Reactions: JonStevens

·
Los Angeles
1993 Wrangler YJ 4.0
Joined
·
2,126 Posts
I generally only use Felpro gaskets, even when a gasket has been supplied with a part. Fel-pro will provide sealant and instructions of where to put the sealant IF sealant is required. If there is no sealant in the box, don't use sealant! That simple. For you guys that use a small amount to hold it in place and been doing it 30 years? You are doing it wrong for 30 years.
To the OP: Go scrape it off and do it correctly and don't listen or do things that people say they have just been doing wrong forever so it makes it right, lol.

Here is a fun little educational video for all of us.
 

·
Registered
Joined
·
2,035 Posts
I trusted Fel-Pro gasket and went RTV-free on my water pump, thermostat, valve cover and timing cover gaskets. Dry as a bone on all of them!
Good clean surfaces and a Fel-Pro. If, in the future you have to swap out one of those parts... No cleaning to be done, a faster job and dry seal. If I had to add RTV, because it was leaking after initial install (due to badly warped housing or something), I would do that. But, anytime I can get away with no RTV... I will.
 
1 - 16 of 16 Posts
Top