Gasket material

Ive got a thermostat housing leak that i just cant seem to cure. Multiple different gaskets, different housing, rtv, etc. Only constants are the parts store gaskets and the intake manifold.

Im thinking about making a gasket from cork, rtving it to the housing, letting it all but cure, add another round of rtv from cork to manifold, and torque it down.

I haven't found anybody using cork in this application.

Is cork a suitable material for this?

What's warped?

I suppose cork wouldn't hurt. You've tried everything else, what's one more failure? Go for it.

Meanwhile, put a straight edge on both faces, the manifold and the housing.

Yup, something's not flat or isn't staying flat.

Cork may not fix it, but keep trying, maybe it will.

Surface the housing on a sheet of emery or wet sand paper taped to a flat, flat surface, figure 8 style. Any warpage oughta show up right away, surface till all flat. Lapping plate be better but who has those. If that don't fix it run a broad flat file wrapped w/ same paper across the manifold flange.

Crack in the manifold? I would think that warpage shouldn't matter if you're slathering it in RTV correctly. How bad of a leak?

I'd look for a pinhole in the housing as well. It may not be the gasket.

I have also doubled up the gaskets with form-a-gasket between all the layers with success.

It was over 2 different housings, 2 different radiator hoses, and 7 gaskets. The housing itself is dead flat. Intake is too near as i can tell.

So, will cork be the solution as it compresses more? Or is there a reason that all the water gaskets are paper?

Like I said, what do you have to lose?

So, we know it's not the gasket, not the hose and not the housing. Humm... Did you try the muffler? Right wheel bearing? Camshaft? Lessee... Manifold? This isn't one of those American made vehicles that crack the manifold where the bolt/studs are, is it?

Pretty fat chance but could the housing bolts go into the coolant passage of the manifold? Seal threads w/ RTV sealer adhesive.

fasted58 wrote: Pretty fat chance but could the housing bolts go into the coolant passage of the manifold? Seal threads w/ RTV sealer adhesive.

This, or are you using a bolt thats a wee bit too long, and is bottoming in a blind hole?

What engine?

Small block mopar with an edelbrock victor intake.

Unknown how muchits leaking.

Cannot find a crack or pinhole.

Bolts are correct length and not bottoming out.

I've had very bad luck with cork gaskets. They tend to squeeze out as you tighten down the part. When I get cork gaskets in a set I use them as a template to make a gasket out of some thick gasket material I bought at the LAPS. I don't have a brand name or part number for you, but it came in a roll, is a medium blue color and is specific to sealing cooling system parts.

Is it an aftermarket neck? Throw it away. They bend at about 5 lb-ft of torque on the bolts.

I had a similar problem with every single one I tried, even the really thick ones with the long bolts. Junk. Billet, cast, whatever, no bueno. Factory aluminum or cast iron is about the only thing you can do.

curtis73 wrote: Is it an aftermarket neck? Throw it away. They bend at about 5 lb-ft of torque on the bolts. I had a similar problem with every single one I tried, even the really thick ones with the long bolts. Junk. Billet, cast, whatever, no bueno. Factory aluminum or cast iron is about the only thing you can do.

+1. Aftermarket water outlets are a guaranteed leak. They just plain suck.

Cork gaskets are also suspect for holding coolant. Some paper ones, too.

If you must keep with the aftermarket water outlet, sand it flat as detailed above and use no gasket, just some Right Stuff. Accept no substitutes. If the surfaces were remotely clean and dry, it WILL not leak.

Dusterbd13 wrote: Small block mopar with an edelbrock victor intake. Unknown how muchits leaking. Cannot find a crack or pinhole. Bolts are correct length and not bottoming out.

Some mopars had the the grove for the thermostat in the housing and some had it in the manifold. When you start mixing and matching and add in aftermarket parts you can end up with the grove in both or neither. Make sure you have the grove, install the gasket on the opposite side of the thermostat from the grove, make sure the mating surfaces are flat, liberally apply brush tack to both mating surfaces and use thread sealant or RTV on the bolts (they go thru to the water passage in the intake)