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Fuel tank sending unit gasket leaks.....quick fix?

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Rewiring the rear of the car with harness and noticed that that are old gasoline stains streaking down the back side of the tank from around the cork gasket that seals the sending unit plate. Bummer. Nothing fresh or wet or even no gas odor. What gives? To take the sending unit out, so goes the tank. Now, this is a Moss aluminum tank that has been in for a few years, with no problems. Till I started looking. I did change the sending unit out at the outset a few years ago. Moss sent me a defective one and I replaced it. Short of pulling the tank, is there any sealer-in-a-tube that I could just press into the seam where the cork gasket sits?
 
Check that the fasteners are properly cinched.

To seal the joint, first clean the area real good then apply a two part epoxy (the stuff that comes in a dual tube) building a bridge from the dop of the sender to the top of the tank.
 
See what others say, but I had to remove my tank to fix that little gasket. When I removed the tank, I noticed that the filler neck was also leaking. Made me wonder if that was the only leak.

While putting the tank back in, I then noticed that it had pin holes.

As you might guess, it was awhile before I was back on the road.

Wishing you far better luck, . . .
 
Re: Fuel tank sending unit gasket leaks.....quick

The idea of epoxy is good, but I would want to get it off there some day, down the road. Instead, I went with a brushed-in layer of Permatex Aviation, saturating the cork gasket and both the tank and the metal sending disk. I let that tack an hour then came back over with a thick, pressed in layer of Permatex Sealant #2, which will tack quite firmly, but never brick hard. Both are gasoline resistant. Hopefully this will seal the minor seepage around that darn cork gasket.
Thanks for the input, just needed to talk it out.

Oh, and my new harness/turn signal switch/blinker works great. Now to put the darn car back together! I had just put it all together a month ago. This is getting old. I feel like Tinster sometimes.
 
Re: Fuel tank sending unit gasket leaks.....quick

Bill,

We used to use this for fuel leaks and to seal the secondary well plugs on the early GM Q-Jets.

Gasoila High Temperature Sealant - 350° Hard set is not affected by alcohol, gasoline, or solvents. Use on porous areas on all aluminum or cast-iron heads; especially on the roof of the ports, and in the spring seat areas. Great on Harley-Davidson heads!

https://www.gsasupplyco.com/
 
Re: Fuel tank sending unit gasket leaks.....quick

Well, I did a really dumb then when I pulled my tank to make sure it wasn't rusting. Yep, I put it back in with the old cork seals.

I'm expecting to have to pull the tank to fix it, and it did leak like crazy much more so than I would have expect a seal to allow.
 
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