Gahhhh!!!!!! 318 Leaking Thermostat Cover

[Aberdumbie]

I keep my engine sparkling & perfectly immaculate. Suits my OCD. Started getting a leak at the thermostat cover a year ago. Perfect opportunity to replace with a sexy cast chrome cover.... Install and drive for a month.. This one starts leaking. I take it off. Apply two gaskets and wrench that puppy down... Drive a month... Starts leaking AGAIN.... Been time for a tear down anyway so we rebuild the top end. While everything is apart I take the intake to a machine shop. They check and the flange is flat as can be. Put it all back together three weeks ago and bought a factory stock thermostat housing... Today it is wet!!!! What the heck am I doing here?? Over tightening?? I put this together with two gaskets and that expensive aircraft gasket sealer. It's making me nutz!!!!

 

[A383Wing]

the chrome ones always leak...toss it and get a stock one

 

[rumblefish360]

Are the bolts loosening?
Blue locktite. Just a dab!

 

[Cranky]

Use one gasket....a thin paper type. Make sure the T-housing is flat too.

 

[Dennis H]

Got a Mancini (overpriced) Billet housing. No more leaks. The chrome one leaked no matter what I tried. Chinese junk. Change the thermostat while in there. Stant Superstat 180 or whatever it calls for.

 

[69roadr]

i had a chrome one too and it failed quickly. get some rtv silicone and follow the directions to the tee, which means letting it set up before assembly.

 

[Cranky]

Got a Mancini (overpriced) Billet housing. No more leaks. The chrome one leaked no matter what I tried. Chinese junk. Change the thermostat while in there. Stant Superstat 180 or whatever it calls for.

Chrome housings are hard to seal. Usually have to remove the chrome on the gasket surface no matter what country made them.....

 

[Badvert65]

I have used the chrome ones in the past. They end up being a one shot deal. Never been able to reuse one. Once they start leaking, nothing can fix it except replacement. Doesn't make sense, but there it is.

 

[MT_Mopar]

I had the same problem, Permatex® the Right Stuff® GREY Gasket Maker will fix it.

Put a thin coat on each side of the gasket. Done - No leaks.

 

[ArtH]

I had the same problem, Permatex® the Right Stuff® GREY Gasket Maker will fix it.

Put a thin coat on each side of the gasket. Done - No leaks.

I've only owned one of these and it leaked no matter what I did. I finally pitched and put an OEM type that was cleaned and painted properly. Problem solved.

 

[440+6]

My original housing leaked so I put my belt sander in a vice and milled it flat, been years now and it's fine with thin gasket and no sealer.

 

[Aberdumbie]

Much much good enlightened info here and I appreciate it all. I believe I am going to put my blade honing wheel to use as a grinding/flattening device, and use the one paper gasket with the thin layer of Right Stuff as suggested. Sounds like my plan to stay out of the way while important work is being performed in my kitchen Thanksgiving morning. Thank you for the good advice.

 

[Aberdumbie]

Such a wealth of info I got one follow up question if I may. I bought stainless steel machine bolts for my intake and thermostat cover when I rebuilt. Could there be an issue with the stainless bolts possibly taking heat differently than the OEM bolts making them maybe prone to coming loose? Sure wish I would have used Lock-Tite... Hindsight being 20-20 and such.

 

[Car Nut]

I heard that if you use stainless steel bolts in metal, you should use loctite anti seize. :dontknow: