Thread: Thermostat question

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I have an "o ring" style on the 302 in my T and knock on wood it has not leaked in the 3 years it has been on there. I too though have heard the horror stories with them. I like the old fashioned gasketed type too. Seems like the old paper gasket is reliable and cheap.
Don Jr.

Do an experiment.....take a thermostat housing and sand it on a
flat surface.....like a piece of glass with sandpaper laid on it.....some
of the cheap chrome crap takes more than a 0.050" cut to make flat....
like Tech said, they leak.

Use a good file and "draw file" the mating surfaces of the manifold and water neck so they are dead flat, use a regular good quality off the shelf gasket, and some heat and water resistant non-hardening gasket sealer (I won't debate the differences between sealer and RTV here), new bolts of the proper length and use the same sealer on the bolt threads; don't over tighten the bolts, and use a torque wrench to make sure they are tightened equally. I've heard it said the God (or, the devil) is in the details; this is one place details definitely pay off, or will bite you in the backside. And, as said otherwise, those fancy chrome "pot metal" water necks are pure junk. Best to use a neck of the same material as your manifold, and if a shiny pretty is called for, get an expensive "manufactured" one, made up from plate and tube that has been fit and welded and surface milled; stainless is a good thing for this.

Each to their own, but I've never had one leak using good old Permatex 2 and a stock style gasket.