Aluminum intake manifold sealer

[Michael G.]

What's the best gasket sealer to use around the water jacket ports on the L84 intake manifold (base plate) to cylinder heads?

[Bruce B.]

Re: Aluminum intake manifold sealer

I like Permatex #2.
Use just a thin film on both sides of gasket and torque to specs.

[John D.]

Re: Aluminum intake manifold sealer

Michael, Put a straight edge on your FI baseplate. Then do the heads.
Be careful torquing the aluminum though. Those front corners break off easily if your baseplate isn't true/straight.

Meanwhile old JD hates messy Permatex. But as Bruce says #2 is OK as it doesn't set up like #1 and #3.

You didn't ask but on the top water outlet gasket use GM 10105135. Just the special gasket and nothing else.
Use your surface plate to sand the bottom of the water outlet as they are typically warped.

Certain studs holding the base plate on could use a little Permatex too.
But the biggest issue is the crappy rubber end seals. Good luck, JD

[Timothy B.]

Re: Aluminum intake manifold sealer

I wanted to share my experence with intake manifold gaskets.

On my 67 cast intake I used a old NOS GM intake gasket and put #2 sealant around all four corners (water holes) top and bottom of gasket. I have observed VERY small seepage after the car cools from a drive. May be one-two drops but I have noticed this on all four depressions in the intake gasket like it's seeping through the old gasket materal.

System goes under pressure fine without excess pressure. Be careful with repro radiator caps, I checked mine and relief is 17lbs.

Manifold bolts are snug, it's something you can put a paper towel in to just pick up and there is no further seepage. Installed the manifold without any problems using a plastic guide at the distributor hole. I know it's been mentioned about the stop leak tablets in previous posts and here is a good place where they were used.

The seepage seems to be less and I am not worried about it causing any problems. I refilled the syster with the Zerox Z-05 with de-mineralized water, this product may be more prone to finding seepage in our old systems. I also used super weatherstrip adhesive on the end gaskets to block and a dab of ultra black in the four corners with no other problems.

[Ridge K.]

Re: Aluminum intake manifold sealer

I wanted to share my experence with intake manifold gaskets.

On my 67 cast intake I used a old NOS GM intake gasket and put #2 sealant around all four corners (water holes) top and bottom of gasket. I have observed VERY small seepage after the car cools from a drive. May be one-two drops but I have noticed this on all four depressions in the intake gasket like it's seeping through the old gasket materal.

System goes under pressure fine without excess pressure. Be careful with repro radiator caps, I checked mine and relief is 17lbs.

Manifold bolts are snug, it's something you can put a paper towel in to just pick up and there is no further seepage. Installed the manifold without any problems using a plastic guide at the distributor hole. I know it's been mentioned about the stop leak tablets in previous posts and here is a good place where they were used.

The seepage seems to be less and I am not worried about it causing any problems. I refilled the syster with the Zerox Z-05 with de-mineralized water, this product may be more prone to finding seepage in our old systems. I also used super weatherstrip adhesive on the end gaskets to block and a dab of ultra black in the four corners with no other problems.

As a 17 year old kid, I went to work at a dealership in 1971. On warranty issues, the Chevroley mechanics were required to use GM engine gasket sealants.
On used "dealership stock" units, the mechanics only used 3M super weatherstrip adhesive.
Was this the best.......? I don't know, but I've used it ever since 1971 without a failure.

This tip worth exactly what you paid for it.........
Ridge.

[Michael G.]

Re: Aluminum intake manifold sealer

Thanks guys,

I used the Permatex #2. You're right John, it sure is messy, and it doesn't wipe off your hands when wet like the silicone stuff does. I managed to assemble it to the recommended torque spec without snapping of any of the manifold bosses, so I think we're good. I didn't take off the thermostat cover, so I'll remember your advice for another time, John.

You guys may note that I made the manifold bolts into my MAThread anti-cross thread points and they aligned the manifold very well without any worry about thread damage or jamming. (Current Corvettes use them all over the place, but, '63's were a assembled quite a bit before I invented the parts). I don't usually produce or sell 'em myself, so I may get one of my licensees to produce those particular parts, they really made the manifold job easy.