Fuel leak source?
Thread Starter
Burning Brakes
Joined: Dec 2004
Posts: 918
Likes: 5
From: Gainesville FL
Fuel leak source?
I filled my newly-purchased 76 TT with gas last weekend and took it around the neighborhood this morning to run it a bit. When I got back to the house after 10 minutes of driving, I noticed gas dripping from the bumper connection point at the right rear. I couldn't find the source of the leak, but it was definitely coming from somewhere on the fuel tank. The leak wasn't fast, about one drip every two seconds, and it lasted for 20 minutes or so, then quit. This is the first time that this has happened, as far as I know.
What puzzles me is that I didn't see any leaking during the week while the car was parked, although I did notice a gas smell when I had it in the garage. Is there a vent tube on the fuel tank that has been disconnected or something like that? Or is this a symptom of a tank leak in a specific area? Bubba gouged up the fuel filler neck so that he could add leaded gas when that was still sold, so I wouldn't put anything past him!
What puzzles me is that I didn't see any leaking during the week while the car was parked, although I did notice a gas smell when I had it in the garage. Is there a vent tube on the fuel tank that has been disconnected or something like that? Or is this a symptom of a tank leak in a specific area? Bubba gouged up the fuel filler neck so that he could add leaded gas when that was still sold, so I wouldn't put anything past him!
Drifting
Joined: May 2001
Posts: 1,651
Likes: 13
From: Holly MI
One thing to look for is the sending unit leaking. The unit uses a cam lock feature to lock into the tank. There is an o-ring between the two pieces. Mine has been leaking there off and on for a while. I have replaced the o-ring without much improvement. What I had to do was massage the tabs and cams to increase the amount of compression on the o-ring. All this is much easier done with the spare tire carrier removed. Taking that off will let you see all the connections and possible leak points.
Ken
Ken
Racer
Joined: May 2004
Posts: 301
Likes: 2
From: Boca Raton Fl
Originally Posted by Vette Gator
Is there a vent tube on the fuel tank that has been disconnected or something like that?
I can see a vent tube running off to the side.
When I fill er up it will also drip drip drip onto the RR muffler
I can see the tube up there.
I need to extend the tube down past the muffler, I Guess
Can't find illustrations on fuel tank diagrams to know any better
Advanced
Joined: Aug 2004
Posts: 98
Likes: 0
From: San Gabriel CA
I had the same problem with my 76. There are two rubber lines at the top of the fuel tank that crack over time. Drop the fuel tank and inspect those lines. They connect to two metal lines that run along the inside of the right frame rail. Its pretty easy to change the rubber lines with the tank down. I had a slow leak coming from near the fuel tank. Couldn't tell where. I soon as I dropped the tank, it was pretty obvious.
Team Owner
Joined: Aug 2000
Posts: 21,449
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From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
Cruise-In VI Veteran
St. Jude Donor '08-'09-'10-'11-'12
No, not really. Up to '74 they were easy as the sending units were at the bottom of the tank, so were these rubber fuel line connections. 1975-'82s had top fuel tank connections & also '75-'77s had a "safety shield" over the tank which made it harder yet to get to the lines exiting the top of the tank. You may get away with "lowering" it a few inches to get to everything, which includes lowering your passenger side muffler also to allow access to this area.
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