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Thermostat housing gasket

KBMWRS

KBMWRS

sad
Donator
Me thinks I be leaking around where the housing attaches to the top of the block. So I'll be doing a coolant flush and replace the gasket.

Simple question. Does the gasket go in dry, or should I use a gasket sealent? Its just the usual paper/cardboard type gasket.
 
No gasket, Permatex the Right Stuff gasket maker. I use this stuff for about everything and haven't had a single leak yet. I buy the stuff in the metal propellant can, as it makes for easier cleanup and you get more.
 
I've just put a little dab of sealant on the thermostat edge in a couple of places to hold it in place, and put the gasket in dry. So far, never had a problem with one leaking.
 
I've installed the housing with just a gasket, dry. Gasket with a little sealer and no gasket and Right Stuff. None have leaked.

Important part is to stay away from the chrome housing, so I've heard / read.
 
If you put the flat part of the chrome housing up against the 6" or 12" sanding disc, they seal pretty good but it is true, they do leak more than the cast or pot metal ones. I put high tack on the side of the gasket that goes to the housing and a thin layer of sealer on the block side. The reason for that is so the gasket will come off with the housing and not stick to the block. I do the same thing for water pumps, timing covers, fuel pumps, valve covers etc.
 
"silverblueBP" said:
Important part is to stay away from the chrome housing, so I've heard / read.
Click to expand...

They get a bad wrap for a reason. The chrome ones don't use gaskets but rather an O-ring. The problem with the O-ring is that it isn't thick enough to give a good seal. Its not a simple round O-ring, otherwise I'd just get a thicker o-ring. I'm running the chrome one, but with the seal removed and the Great Stuff in there. Looks good and no leaks :thu
 
"66gt350" said:
I've just put a little dab of sealant on the thermostat edge in a couple of places to hold it in place, and put the gasket in dry. So far, never had a problem with one leaking.
Click to expand...

+1

plus make sure the housing is flat (not warped)
 
Installed with no problem.
Used some sealer on both sides.

My original problem was a drip notice occassionally on the agrage floor. Clear/yellowish liquid. Coolant. But toward the back of the engine. Odd?
IMG_2068.jpg


Checked under the car and the top. Noticed that a trail of dried coolant was coming down from the thermostat housing (also noted the dried gummy stuff on manifold)....
IMG_2062.jpg


IMG_2065.jpg

IMG_2063.jpg


down to the block along the top of the oil pan and then dripping off. By the time it reached the floor only the raw coolant was left, water being all boiled off.

And since it would only happen occassionally it was probably due to the length of time of the drive.

Tried to install a new thermostat while I was at it but both O'Rielly and Autozone both offered up a 289 version. Had nothing for a 390. Since it was Christmas Eve by the time I got to NAPA it was closed. I'll try again this week. For now though its all drained, cleaned, backflushed and new coolant/water wetter/ distilled water added. :thu
 
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