Well I got my hole tapped out and the new bolt is going to fit fine, looking around and realize that I didn't get a new gasket with the tstat and the old one is wasted. Can I use just RTV, or do I need a gasket too?

 

get a gasket and do it right the first time. That way you wont have to worry about it again. Tried the no gasket once and it wasnt pretty

 

Well, the gasket is a good thing to have. Not only does it seal, but it kinda keeps the thermostat in place....from rattling around. You'll see what I mean ...because of the mating surfaces. I would say, though, if you can layer the RTV on thick enough and it cure fully before you install it, it would in all likelihood work just fine.

 

On second thought, I believe I've even done it before. I was in a bind like you. Only I believe I used the old, busted gasket in conjuction with the RTV. As I recall, it worked fine for a while. I did eventually put a new one in, though.

 

it will work for awhile if you do it right. on my old 1982 Honda ATC250 3 wheeler, i had to make a RTV gasket along with the old one that connects the engine to the exhaust, or something. i just know it was cracked and it had bad performance. fixed it, was good. had to fix it after every desert trip. then i found a place that had some factory gaskets in stock(hard, since they were discontinued) and installed that. had no problems, and its still runnin strong with my cousin, who bought it from me and took it down to FL.

 

I'd only do it on a temp basis. Sounds like a job for the Right Stuff.

 

Look real good it the box, my last t-stat gasket was hinding under a flap inside the box, trying to make a get a way hehe.

 

o yeah, those gaskets love trying to make getaways.

 

there cheap just do it right

 

Binds will do that, I've made o-rings out of duct tape before.

I would recommend getting a new one if you can. It does keep it from moving around and if you do it right the first time, you wont have to do it again....

 

I'm sure you could get away with it but as mentioned the gasket is so cheap it's better to do it right the first time. I usually use a new gasket and I still dab a light layer of permatex around it just for luck.