Gas Tank Leak Repair
Scott Simpson - Scott231@Juno.com
Introduction
If your tank starts leaking, chances are it is leaking from underneath the straps. Moisture becomes trapped between the tank and straps causing small rust spots to begin. As the rust gets through the tank metal, leaks begin.
Tools Needed
  1. Deep Sockets,
  2. Extension,
  3. Ratchet,
  4. Screwdriver (to get pump out),
  5. a sharp pick (such as a dental pick),
  6. gas tank repair putty,
  7. sandpaper,
  8. primer, and
  9. black paint.
Remove Tank
  1. Drain gas from tank (either run it dry or jumper the pump primer wire and drain from rail).
  2. Disconnect 3-wire fuel pump connector which is behind the rear bumper, driver side.
  3. Remove straps from tank by loosening the two nuts holding the straps.
  4. The vertically mounted bolts are between the factory crossflow muffler and the gas tank.
  5. It may be a little tight but should be accessible if you use an extension. Either have someone else hold the tank up, support it with a jack or use your free hand to keep it from falling out once you remove the nuts from the bolts.
  6. Lower the tank about half way and remove the hose clamps on the three lines going to the fuel pump hanger.
  7. Slide tank out towards the differential.
Remove Pump
  1. There is a metal ring holding the pump/hanger assembly in the tank. To remove it, place screwdriver against one of the tangs and tap in the direction that the ring will turn to loosen.
  2. Once the ring is popped open you can carefully angle out the fuel pump/sender hanger assembly. (What does it look like in there? Maybe you should clean the inside!)
  3. Now flip the tank over expose the bottom of the tank.
Prepare Tank
Remove the rubber straps (attached by Velcro). You'll probably see where the tank is leaking badly right away.

However to do the job properly, sand the bottom of the tank to the point of removing any paint or coating that is on the tank. (I have never seen a tank leak from the top or sides, but you can always check.)

You will probably now see additional points from which the tank is leaking. There is usually a skid plate on the center of the tank. This plate is attached with some goo from the factory. Remove it and check tank surface for more leaks underneath.

Repair Tank
  1. Using the pick, ream out any hole that is leaking.
  2. Now ream out any rusty or pitted spot that does not appear to be leaking. You may have to jab the pick through the metal but it's better to do it now than to let rust take its place!
  3. Once satisfied that you have found every possible leaker or weak spot, use the gas tank sealer putty to fill in the holes. Go ahead and apply liberally.
  4. Let the putty dry according to manufacturer's instructions.
  5. If you had a skid plate and removed it earlier, you can reattach it with the sealer putty or discard.
  6. Prime and then paint the tank
Replace Pump/Sender Assembly
(BTW, this is a good time to change your pump, fuel sock and/or upgrade your pump wiring!)

Carefully insert the pump/sender assembly back into the tank, making sure the fuel sock is located where it will not interfere with the fuel level sender. Tighten the ring and reattach the three lines. Replace tank against trunk floorboard and re-tighten retaining straps and nuts.


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