Fuel Tank

General Information

I tried installing the 87 GT tank my 85 when doing the 3800 swap. No go- It bottomed out on the sides with still 1 1/2" to go. Apparently, GM modified more than just the tank to get the extra fuel capacity.

From: Dave Cole

Removal and Installation

Removal - all models

1. If you can still drive the car, but are replacing your fuel pump because it's starting to flake out or something, drive it until it's almost out of gas. This will make removal of the fuel tank MUCH easier.
2. Remove the Fuel Pump fuse. It's at the top one, second closest to the driver's door.
3. Start the car and let it run until it dies. Do this until it won't start anymore to relieve the fuel pressure.
4. Disconnect Negative battery cable.
5. Jack up BOTH ends of the car and place it on jackstands, so that the car is level. On a GT or aero-nose SE it is easier to jack up the front end first.
6. Remove the catalytic converter heat shield.
7. Disconnect the connector for the fuel pump. I found it about halfway up the firewall, right between the A/C hoses which are wrapped in silver insulation.
8. Loosen the clamps on all of the hoses at the back of the fuel tank.
9. Find an empty soup can or something. DON'T use a plastic/styrofoam cup, because the fuel will most likely cause it to melt.
10. I removed the fuel sending hose first, which had most of the fuel in it. It sprays a bit at first so it's hard to catch some of the fuel. Next, I removed the return line which had a little bit of fuel in it, but not much. The line for the vapor canister, and the two large hoses for filling didn't have any fuel in them.
11. Remove the four 13mm bolts on the main support underneath the fuel tank.
12. Place a floor jack under the rear end of the fuel tank.
13. Remove the 13mm nut from the rear support strap, then the front.
14. My fuel tank stayed in place, but yours may want to fall down, so keep a hand under the front end of the tank (as long as it's pretty empty).
15. Lower the jack, and move the tank out from under the car. You may need to pull on the tank as you lower the jack to get it to come down.

From: Sketch