I've made two gaskets for the fuel sender. One from gasket material that you would use for a water pump or t-stat housing. The second one from cork sheeting. Both leaked. Should I be using gasket cement or thread sealant on the attaching screws.
Any ideas?

 

Dont know what tank you are working on but most 60's had a rubber type O ring to seal. I would use that.

 

It's a 62 starfire. The rubber gasket disentegrated when I removed the sender to have the tank cleaned. Ames Performance sells a sender gasket that looks like the right one, maybe I will try that and use some thread sealant on the screws.

 

I removed the sender AGAIN. In addition to the gas leaking at the attaching screws, the feed pipe was leaking where it passes thru the base. There is a little indent around the feed pipe. I filled it with fiberglass resin to seal it. It is hardening now. I made a new cork gasket and glued it down with Permatex High tack gasket cement. I'm gonna apply some to the threads and the other side of the gasket when I reinstall it.
Both materials are supposed to be gas resistant. We will see.

 

Rubber is the only thing I can think of to use, as long as it is resistant to gasoline to avoid deterioration.
Other materials like cardboard and cork are porous and would let the small gas molecules through.

 

Gasoline-resistant rubber is "gas resistant" because gasoline won't attack it chemically and dissolve it. It's not "gas resistant" because it doesn't let molecules of gasoline through. Gasoline molecules are actually relatively large as molecules go. They're much larger than, say, water molecules or molecules of oxygen, nitrogen, or ethanol.

In fact, if gasoline molecules were much larger, gasoline wouldn't be a liquid at room temperature.

 

Jaunty, you misunderstood me due to how I phrased my sentences.
Rubber will seal gas the best, but the rubber must be resistant to gas so it will not deteriorate.
I clairified my post above.

 

Thanks,
I think I was loosing more gas where the feed pipe is soldered to the base plate. Fixed that. I agree fuel resistant rubber would be the best choice. I applied a liberal amount of High Tack gasket sealer to both sides of the cork gasket I made and applied some to the screws. It has been curing since yesterday morning. I will let you know if it works.

 

You know, between you, me, and the grand piano, what you're doing here would make me nervous. I don't think that gasket sealer or anything like that was used originally to make the seal between the sending unit/intake and the tank. There was just a rubber o-ring that should compress and seal the joint if everything is working properly.

If this doesn't seal your tank, you should fix the problem instead of going around it by gooping copious amounts of sealer on it. That will never last in the long run given all the vibrations and general bouncing around cars go through in life, and, especially given that you are talking about sealing gasoline here, it's even more dangerous as any kind of a break in this seal could result in a gasoline leak.

Then, on top of all this, you're talking about an area of the car that is difficult to get to. Dropping the tank to get at this when it inevitably starts leaking again is nobody's idea of a picnic, and you don't want to have to be doing this again in six months. As I say, better to fix it properly and then not worry about it for the next 30 years.

 

Thanks. Actually, in reading your original post, I see how I misread it.

 

I agree that the cork and gasket cement was not the best choice. I did some searching for gasoline resistant rubber. Buna N Nitrile seems to be the right material. I ordered a 12" X 12" X 1/8" thick sheet of this material from WWW Grainger. When it comes in, I will remove the cork and gasket cement and make a new gasket.
The sending unit is not that difficult to remove and does not require dropping the gas tank.
Thanks for everyones input.

 

Yep! I think you're on the right track now.


I wish this were true for mine.

 

Tried a bunch of stuff on gas tanks before (long story and different model than above). This is the only thing i found to work:

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