leaking fuel sending unit

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wwwfora

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Guys I need some quick help! I just had my fuel sending unit replaced by a shop, I filled 10 gallons of gas in it and it's dripping like niagra falls. How could they screw up so bad. The shop is to far to drive or tow to, so I'd like to do it myself. Could the seal be put in wrong and if I replace it, could I use some kind of compound to help seal the unit when I connect it back up?

Thank you...always something :)
 
make sure the lock ring is tit and make sure they even put the seal in
 
Uggh, most senders come with a new seal and locking ring. Some of those locking rings are too thin and fail to seal. I reused the original ring on mine.
I dont know of a sealant that will work there. I wouldn't start on it without a new seal in hand. OEM lock ring too if I could find one. Good luck
 
FABO! Rocks! Thanks all for the quick response. I'll give it a shot and let you know the results. Gas pouring out onto concrete these days is not the best investment!!!

CHEERS!
 
I dropped my tank and pulled the sending unit out. It was really loose, and there is no way it was tight enough to seal. I'm guessing this aftermarket seal is crap. It's actually really thin and cheap. I don't think I have the patience to wait around for another seal. I'm going to see if I can find some type of caulking that might do the trick and report back.
 
I dropped my tank and pulled the sending unit out. It was really loose, and there is no way it was tight enough to seal. I'm guessing this aftermarket seal is crap. It's actually really thin and cheap. I don't think I have the patience to wait around for another seal. I'm going to see if I can find some type of caulking that might do the trick and report back.

If the rubber seal is not torn or dry rotted then reuse it. DO NOT USE CAULK OF ANY KIND! Don't ask how I know!

All needs to be done is make sure the lock ring is tight against the seal and tank. When I installed mine I just didn't think it was tight enough but I installed it anyway and it does not leak. It doesn't seem to take that much to seal it.. good luck!
 
If you dont have the special tool you should have to tap the ring to gget it turned all the way to the stops. If it turns that far by hand the ring is too thin. Dont go messing with the tank either. If you warp that sealing surface it might never seal again.
 
Thanks again all for your input. I noticed that no only was the replacement seal thinner, but the lock ring is total junk on the new unit. I know they say not to use the old lock ring, but I was stoked to find out that the mechanic left the old ring in a box, so I reused it. Much stronger, thicker and could feel the seal as it locked into place. I did use a small bead of Permatex RTV, figured it couldn't hurt. I'm going to fill her back up tonight and see what happens in the morning and get back! CHEERS!
 
Some sealants are incompatable with gasoline. they can swell up many times their original volume.
A friend of mine rebuilt a fuelpump on an aircraft engine.
He put a little skim coat of RTV on the new gasket thinking that "it couldn't hurt".
The airplane only got 100 ft in the air when the engine quit and had to land in a bean field. Lucky landing with no damage to the plane.
The fuel line and filter was plugged with gelatanized RTV that seemed to be nearly 50 times more than he had used. maybe even into the carb.
I know they had to do a teardown on that just to be sure.

So no RTV on anything near gasoline for me.
 
Scary story, I'll scrape it off before I put it back in. Besides using the old locking ring, really feels snug. Thanks again all!
 
Scary story, I'll scrape it off before I put it back in. Besides using the old locking ring, really feels snug. Thanks again all!

I used a "small bead" of RTV .... once the gas got to it the RTV fell into the tank... it swelled up enough to clog up the fuel sock. It didn't totally stop the flow of fuel but it slowed it down enough to cause problems. Now you happy... you made me tell what happened to me! LOL!

Just kidding... I'm glad you're going to scrape it off.
 
i find it hard to believe 10 gallons put the fuel level to the seal. are uou sure it wasnt the small piece of rubber hose between the tank and fuel line. did it leak all the time or only when running? fuel pump pulling.
 
BTW Redfish you nailed this one!...so the RTV stories are still rolling, come on people be honest :) Daredevil, I probably lost about 5 gallons, and of course as the gas level decreased so did the pressure and the loss of gas...attention to detail I see :) I could have pulled the sending unit out with the tank installed, but I dropped the tank for exactly the reason to check the entire unit, clamps, hose, pump fitting etc. It was leaking out of the bottom of the lock ring, it was obvious. Like I said the fault was in the actual cheap lock ring that came with the unit I bought online, the lock ring is crap, and not as thick as the original. No leaks so far....stay away from Item Number 1A-FSU-00007 69-74 Chrysler "A" Body Gas Tank Sending Unit from 1.a.a.u.t.o DOT com. Unless you like nice premium fuel all over your little town :) Actually, the owner of The Round up pizza place called the cops, because my car was pouring fuel, when I got out of the store, it was my cop friend calling me on my cell...pretty funny. The only thing I got out of this deal was a cool police escort home!

Thanks all.
 
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