Fixed persistent thermostat housing leak.

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cpearce

cpearce

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Like many others I have fought the persistent leak from my thermostatat housing, although a minor leak it is very aggravating.

I tired a factory aluminum housing, an offshore chrome one, the offshore chrome one machined flat (only to warp again) in short order, "The Real Gasket" (sealed great until it blew out twice on backside bathing entire under hood with coolant). As well as the "Real Gasket", I tried stock paper gasket dry, with rtv, using Gasgacinch, shellac, etc.

I now have a Billet Specialties aluminum housing with o-ring, so far so good!

Intake is Edelbrock Victor W2, has some very minor pitting (as per usual) around the sealing surface.

I use Evans Coolant, low pressure cap, and factory water pump.

Will post photos later.
 
Hmmm just must be lucky I guess as I have never had an issue on 4 different engines now. Most seem to struggle with common sense and the basics....a good quality housing or a sanded flat OE one, a good gasket like from Superformance and a very small bead of RTV and zero issues. Oh well maybe it's lottery ticket buying day.
 
'68cuda416 said:
Hmmm just must be lucky I guess as I have never had an issue on 4 different engines now. Most seem to struggle with common sense and the basics....a good quality housing or a sanded flat OE one, a good gasket like from Superformance and a very small bead of RTV and zero issues. Oh well maybe it's lottery ticket buying day.
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I might say fortunate rather than lucky......

"Most struggle with common sense" hmmm, pretty bold statement. What are you suggesting about yourself with this line, just curious?

Although I agree, a pretty simple setup, which should be easy enough to deal with, many have struggled with this. I have not had this issue on any of my other vehicles. I also agree that many times the factory parts are best, I could not make that seal after verifying it was true on a thick piece of glass. Very surprising was an aftermarket one machined flat on a Friday, was warped by Sunday with coolant never exceeding 185. I suspect porosity problems in the metallurgy.
 
Another issue many people neglect is the fact that many manifolds (especially aftermarket ones) have one or both of the thermostat bolt holes that are open to the coolant passage. If no sealer or tape is used on the thermostat housing bolts, this can result in a persistent, although minor, weeping type leak at the housing that many mistake for a failing gasket.
 
'68cuda416 said:
Hmmm just must be lucky I guess as I have never had an issue on 4 different engines now. Most seem to struggle with common sense and the basics....a good quality housing or a sanded flat OE one, a good gasket like from Superformance and a very small bead of RTV and zero issues. Oh well maybe it's lottery ticket buying day.
Click to expand...
Same here.
 
Previous owner of mine had similar issues... this is what the intake looked like after repeated blow outs.

20200516_191724.jpg


I went with a Billet specialties o-ring housing as well. The countersunk holes on mine were off a tad so I just used a longer bolt. After shot of the same intake, shame you can barely see it as it's a nice piece of kit.

20220801_111425.jpg
 
I went through a few oe housings, and at least 4 aftermarket chrome ones, sanded flat, top quality gaskets, sealers, the whole gong show, all leaked. Finally I put in studs, with thread sealer, more top quality gaskets, lockwashers and nuts. Leak over.
 
Professor Fate said:
Another issue many people neglect is the fact that many manifolds (especially aftermarket ones) have one or both of the thermostat bolt holes that are open to the coolant passage. If no sealer or tape is used on the thermostat housing bolts, this can result in a persistent, although minor, weeping type leak at the housing that many mistake for a failing gasket.
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True....but seriously shouldn't that be common sense? I mean if someone was to overlook that then maybe said person might be seen trying to screw 2 nuts together, LOL
 
Make sure the recess in the housing is deep enough to seat the thermostat correctly.
 
74Scooter said:
Previous owner of mine had similar issues... this is what the intake looked like after repeated blow outs.

View attachment 1715994908

I went with a Billet specialties o-ring housing as well. The countersunk holes on mine were off a tad so I just used a longer bolt. After shot of the same intake, shame you can barely see it as it's a nice piece of kit.
Click to expand...
Those pot metal chrome housings like to warp and leak..
 
Old cast iron ones blasted and painted. Or Stainless O Ringed ones I polished. Yes I know the intake is not shiny enough, it was just a 1st cut to get rid of sand scraches. Still had to gray emery, white and blue rouge and hand polish clean up for "Color/ Depth"

AIR1.jpg
 
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