thermostat housing leak

[Spoolin98]

I have a small leak coming from my thermostat housing. Its not leaking from the upper or lower radiator hoses. Its leaking from the bottom of the housing where a pipe connects and runs behind the exhaust manifold. I know where the leak is, just dont know how to fix it? Where the pipe connects to the housing its metal on metal and there is no visible seals or clamps. I checked the Haynes manual and it's worthless like always. Any help or suggestions are welcome.

 

[negativezero27]

wow i have been searching on this subject and i can't find anything. I'm having the same problems aswell. Could someone tell me if there is an o-ring that goes there or just some rtv.

 

[squeak104]

Where the water pipe goes into the thermostat housing, there is an o-ring around the pipe that may be leaking. My problem was the thermostat housing itself. There isn't a gasket, you just lay a bead of RTV in a groove thats in the thermostat housing and bolt it together. Thats probably where its leaking from.

 

[negativezero27]

yeah its leaking all around it. I just didn't know if they had an o-ring that goes around it to seal it or, you just put some rtv around it. If they required an o-ring i didn't know what to ask for at the auto part store.

Thankz for the help though.

 

[squeak104]

If the o-ring is leaking its probably going to be a dealer item only or at least it was for me. Napa, Advance, and Autozone didn't have it for me. If the ring isn't torn I'd just put a little rtv around the o-ring to make sure it doesn't leak. If I remember correctly the pipe has to come out to move the thermostat back far enough to put rtv on it. Good luck.

 

[negativezero27]

i was just going to pull the t-stat housing off the pipe. Do you what part name the o-ring is called?

 

[squeak104]

Um I'm not sure but if I'd have to guess I'd just say its an o-ring for the water pipe. It takes two o-rings (one on the thermostat housing and the other on the water pump). If you need to replace it carefully take it off and take it with you to the parts store. If they don't have the exact one for your Eclipse then they may have one for another vehicle like it. Or check in Home Depot's faucet section. It's worth a shot. Good luck.

 

[Styl]

Couldn't find much info on this, and I'm not sure if the answer is in this topic or not, so I'll go ahead and ask. My thermostat was starting to go bad, so I got another one and went to put it on. Got a thermostat gasket too, but I'm thinking that Advanced gave me the wrong one, because it doesn't quite cover the entire mating surface. My problem is that I put the RTV on both sides of the gasket mating surface, put the gasket on and put it all back together... Now I have a coolant leak from where the gasket is (almost all the way around the whole gasket), and the cars starting to overheat from coolant loss. Do I even need a gasket there? Will RTV just be enough? I'd appreciate some help soon as possible, gotta drive to work tomorrow.

 

[bane3d]

Well, I was moving my car into the driveway and after starting it up, moving it 15 ft, and parking it, I looked underneath. I saw this drip coming down fairly quickly. I traced it up and found the leak was underneath the thermostat housing like everyone else in the thread here. I can see a small pool of coolant sitting on top of the transmission and it appears that it's got kind of a major leak. From the previous comments, the recommendation was to run a bead of rtv seal around the pipe on the bottom. This seems like a temporary fix to me. How much of a PITA is it to remove the thermostat housing and actually fix this problem? Should I purchase another housing and just replace it? Also, since I've never done this before, will it drain an @$$ load of coolant all over my drive way and put air in the coolant system? How do I properly remove the air out of my coolant system after I put it back together? And finally, since this is a brand new engine swap and I'm assuming they had to replace my 2G thermostat housing with a 1G, this part is actually faulty, should I contact the place that sold the engine to me and have them ship me a new one or should I just try to repair it? I appreciate any insight since this will be my first major garage mechanic job on the car since I didn't feel comfortable doing an engine swap myself.

d

 

[marshall13]

It's called a thermostat housing seal set. And you can get it at O'reilly's on special order if you can get the counter hand to actually spend a little time on it. As for there being no gasket there, you can also get t-stat gasket blanks at O'Reilly's (they are on the shelf in the aisles) and cut it to size on the housing. THEN throw some RTV on it so the seal will last longer.

 

[bane3d]

Thank you. That's what I wanted to hear. I read through some searches and according to Defiant, our systems will purge themselves of air through the coolant reservoir after 2 or 3 heat cycles. I'm guessing that as long as I'm careful, I should be able to get this done in a few hours easy and let sit overnight to cure (RTV sealant). Does this sound right?

d

 

[rb25det510]

yes to be safe just let the car sit over night so the rtv can set. but usually what i do to purge the system of all the air bubbles is i fill the system up until it is filled to the neck then i start the car. after this the level will go down and it will start to purge the air out on its own keep filling until no more bubbles come out and the level at the neck starts to rise then put the cap on and your done. keep an eye on your temp gauge cause it may not have purged completely and it may overheat. but ive done it countless times this way and its never happened to me but it can happen.

 

[thewraith]

As a late update here. I tried both blue and copper rtv and it did not work- both leaked. I finally gave the gray a try and "viola" all is well. It apparently dries harder and forms a better seal. I should have known better since the oem seal was also ultra gray. As mentioned earlier- there is no OEM gasket for this.

 

[Daaan]

I have a 1992 talon and im doing an engine rebuild. i bought a prestone t.stat to repalace the old one for good measure. there was a gasket between the housing and also between the block. I just made my own with a gasket set, with the oring i used high temp gasket maker. works great.

 

[loba]

Sorry to necro-bump this thread, but it's relevant and was a good find for me. I wanted an opinion on whether or not I should change my thermostat at the same time I'm dealing with this leak?

And is there a good OEM mitsu store to buy the gasket set?

Thanks tons.

 

[thewraith]

just to help out a little... most thermostat housings have some sort of seals... if it is leaking even with a seal, then it is probably warped(if it is then napa or checkers sells them and there not that expensive) or could just not have been put on right

As I mentioned to you guys before. There is NO GASKET set available for this from mitsu or any other manufacturer for the 2g's. Simply make your own seal w/the type rtv I mentioned above. And of course you should change the thermostat- it's common sense for a $10 part.