carburetor gasket sealant?

[freak]

Should I use any type of gasket sealant (very lightly) on the carburetor main gasket? They also seem to seep gas at the seam and I wouldn't be surprised if air leaks there too. On this type of application I would use my finger to smear a very thin coat of sealant on the gasket. I know that gobs of silicone can cause a problem. But should I use any at all?

[Brentwood Bob]

vasoline

[Mitch//pa]

carburetor main gasket i assume your talking about the base gasket. i use the good quality copper gskts dry.

[caserider]

IMO this stuff works better than RTV silicone. One can will last a very long time.

http://www.permatex.com/products-2/p...sealant-detail

[redmodelt]

If you have a Zenith then you should not need any sealer between the top and bottom. If it's a Tilly, that could be a different story as they are very prone to warping.

[Purdy Swoft]

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I would never use any gasket dressing on the gasket between the upper and lower housing of any carburetor. If the float is set anywhere near correct, the fuel in the bowl of the carburetor will never rise to that level. Carburetor vacume leaks happen where the flange of the carb meets the manifold. I use the copper gasket at the flange like Mitch says.

[Tom Endy]

On a Zenith carburetor I don't use any kind of sealer on the gaskets. On the flange to manifold gasket I coat it with Vaseline. On the jet threads I don't use any sealer as the threads do not seal off the fuel, the sealing is done by the small fiber washer. I use the black composite washers available from Bratton's. These seal off better than the original red ones. I use the other size Bratton's black washers in each place that calls for a fiber washer. The GAV assembly and the idle jet are pipe threads and neither use a washer. The GAV threads I lightly coat with the Teflon paste used by plumbers.

The ferral on each end of the fuel line I wrap with Teflon tape each time I remove and install a carburetor. This compensates for any distortion between the ferral and the fuel inlet. The seat of the inlet and the ferral is what seals off the fuel, not the threads.

Tom Endy

[jmeckel]

I rebuild Zenith carbs, the one that came in and was the biggest mess and took the longest to rebuild was one that someone had "rebuilt". It had silicone all over the place including in the jets and on the gaskets. Took a long time to get all the little tiny pieces out of all the little corners and passage ways. If the carb is properly cleaned there is no need for any gasket sealer ANY place. If the surfaces are not flat, look for little bits of old gaskets (especially if gasket sealer has been used in the past), small bits of rust, dirt, etc. Once the metal is truly clean and the float level set right, it will not leak. You do need to tighten up the bolt that holds the 2 half's together, not with a huge wrench, but it should be tight.

[tdlmomowers]

I've rebuilt carburetors of all types and makes for years. I never use any kind of gasket sealant or dressing on any of them. No problems as yet. If the sealing surfaces are flat and true,then nothing is needed. If the float level on a Zenith updraft carburetor is correct, there should be no leaks.

[jkeesey]

I use just a light coating of hylomar sealant. It is gas proof and will not come loose and clog your jets like the other stuff. Just make sure you only use enough to cover the gasket and no extra globs.

[Rocketsled]

I use silicone Valve Lubricant & Sealant, or High Vacuum Grease.

[Bob-A]

I use a light coat of axle grease on the fiber gasket.

Bob-A

[Steve Wastler]

I also use no sealers, and have been running homemade gaskets using the cardboard back of legal pads. They seam to be just fine. If the mating surface needs dressed, lay flat on a piece of glass with some fine sandpaper works great. Obviously the bottom is much easier to do, the top is doable after removing float bracket.

[larrys40]

I concur with post #9, Jon, (Jmeckel) as if everything is as it should be with the carburetor you should not need ANY sealer, I know Tom you said you use Teflon but I have dug out Teflon countless times out of carbs and it should not be needed, if the seat is pitted, regrind it with a stone, if the ferrule is bad replace it. If the top isn't flat dress it with a file and check. If the float is the correct height and the needle/seat are doing their job properly there should be no leaks.

If you're having trouble find someone schooled in your area who is.. or get a tested replacement from Berts, Brattons, or someone on the board that is good at carb rebuilding.
Best of luck.
Larry Shepard

[cedar]

I agree with # 10-----if the mating surface is flat the gasket will do it's job.

[Gold Digger]

I've had my share of cleaning silicon out of carburetors and also oil sump screens. I say no to sealer on carb's.

[Purdy Swoft]

I've never had anything but problems with teflon tape. I've been told that I just don't know how to use it. I do know better than to use it. Teflon usually ends up causing problems with the needle and seat.

[Tom Endy]

I didn't suggest that Teflon tape be used inside a Zenith. What I suggested was to wrap the ferrel ends of the fuel line to compensate for any distortion of the ferrel. There is very little chance the Teflon will migrate to the inside of the carburetor. the practice is very affective in curing a dripping fuel line connection.

Tom Endy

[BILL WILLIAMSON]

Originally Posted by Steve Wastler

I also use no sealers, and have been running homemade gaskets using the cardboard back of legal pads. They seam to be just fine. If the mating surface needs dressed, lay flat on a piece of glass with some fine sandpaper works great. Obviously the bottom is much easier to do, the top is doable after removing float bracket.

Steve,
I use an old window glass with valve grinding compound to flatten & check surfaces. I put coarse on half of it & fine on the other half for finishing. I store it, covered with a rag & it can be re-used many times by just squirting a little oil on it.
For those little HARD jet gaskets, I remember that Les Andrews recommended soaking them for 24 hours before use, but he didn't say WHAT he soaked them in??
I rub Vaseline on Ferrules & on the threads of the gas line nuts, it seems to lessen the friction & it seems to help the Ferrule squeeze down properly on the line. Bill W.