Gas tank removal- 84S Auto

rj7630 · 03-10-2009, 02:35 PM

How big of job to drop gas tank? I think mine has either a bad seal for the sender or maybe cracked. It leaks fuel from the tank if I fill it up and let it sit. Actually forms a small wet spot under the tank. It goes away after I burn off a few gallons. I want to drop the tank and see what I can find.

MPDano · MPDano's Garage

If it's like my 81, then it's not that big a deal. i think the hardest part for me was putting the straps back on. It was kinda awkward since you had to push the tank up from the bottom and angle the strap in place a 10mm nut (nut or bolt, I can't remember off hand) in place and thread it. Other than that, it's 1 person job.

Danglerb · 07:02 PM

Two common locations for a leak when full; vent line that runs through the bumper (12), and seal around the sender in the top (11). Lift up the rear carpet and remove the cover over the sender and check for leaks before dropping the whole tank.

My own experience dropping a tank is that disconnecting the fuel lines can be a serious bear.

Here is a nice pict care of DC Auto.

rj7630 · 03-11-2009, 11:23 AM

Thanks for the help guys. I didn't know about the vent line as a potential leak issue. That's good to know. I'll check things out his weekend and see what I come up with.

mrtiffin · 03-11-2009, 04:23 PM

It took me about 15 minutes to pull my tank on my 84 euro, and about an hour to put it back in. I replaced my vent line because it was old rubber and the clamp was rusted. Have fun.

Danglerb · 03-12-2009, 01:46 AM

Took me maybe 6 hours, but doing other stuff in the middle.

First I pulled up the rear carpet, took the cover off over the tank access, disconnected the sender, clamped off the return line and disconnected it from the sender, then removed the sender.

I took off the rear cover on the support frame, put clamps on the rubber line to the bottom of the tank, disconnected the fuel lines up in the right side tire well, and dropped the support frame after disconnecting the fuel pump and filter and fastening them to some suspension part to hang out of the way (messing with the electrical can be insanity).

Drained the last of the fuel out of the tank into a pan, put a support under the tank and removed all the stuff around the filler neck including the cap, then removed the main bolt at the neck that actually holds the tank in place.

Back under the car I cut the vent line through the rear fender, and the vent line to the expansion tank, and then dropped the tank. With the tank out I drained out the last of the gas, the this can be tricky, removed the in tank filter screen. Don't force it.

Not sure if its smart or not, but I then washed out the tank with Simple Green and lots of water, then blew the water out with air and sprayed it down heavily with Marvel Mystery oil and let the excess drain into pan while the tank sat in the sun drying out the rest of the way.

Once doing this the filter screen cleaned up fine, the other time it didn't look good and I replaced it. Anything worn or rubber I like to replace, but don't go nuts, I was all set to replace the rubber isolators for the fuel pump bracket. Mine turned out to be fairly new, and they are NOT cheap parts.

While it was out I swapped in a powder coated support frame with new padding, and attempted, but failed to take apart the sender and clean it.

rhjames · rhjames's Garage

Quote:

Originally Posted by Danglerb

Back under the car I cut the vent line through the rear fender, and the vent line to the expansion tank

be very careful when doing this---those lines have braided steel in them, and one spark will make a big bang---remember that tank will have gas vapors in it.

take extra caution when working around as tanks.

--Russ