Just finished up full 80 series fuel tank replacement. My truck since new, driven on East Coast, finally had a fuel smell I could not eliminate with the obvious Fuel Canister blockage etc issues. It was a tank leak from seam. Very rusted.
Process:
Remove Passenger Seats to access port and see if leak may be from failed gasket or fuel lines. Not the issue.
2. Moved on to inspecting outside of tank with bore scope. confirmed leaking gas. (sorry no photos of this scope shots)
3. Time to remove tank. First Drain the Tank from the Drain Bolt. Auto Fuel is about 6.5 lbs per gallon so even 10 gallons will add 65 lbs to the Drop. Start with removing the 2 bolts that hold the fuel straps together. If lucky, with enough Kroil and heat, bolts will come out without snapping. Breaker bar with swivel head did the trick on all but one. The one that is on driver side closest to the front had to be drilled out. If I had known the future problem that specific bolt would cause (partial body lift), I would have gone slower and more carefully. So those doing this job, be particularly careful with this bolt. If it snaps and you ruin the thread on the Strap Nut drilling out the bolt, and you want to replace that small strap, you will need to lift the body off frame to back the bolt out holding it to the body!
4. Ok once strap bolts are removed, you can loosen the Hose Clamp from filler tube and the pinch clamp from vapor tube towards the back of the tank.
5. Remove the gas lines from the top of the tank through the access port to "free" the tank from the rest of the truck. (see image above)
6. Now, I was able to jack the front of the car up, and sneak the tank out the front without dropping the drive shaft from the back. BUT, knowing now that in order to get it back in easily, you really should remove the drive shaft in the rear and suspend it out of the way (leaving the front attached is fine) with bungee cords, I would have made my life easier just to remove the drive shaft in the first place. Make sure to remember to mark the shaft and flanges with white out or paint so re-align for proper harmonic balancing retention.
7. OK, now the tank is finally out! My neighbors wonder about the new Garden Ornament...
8. Remove all the fuel sensor components from the center of the top of the tank. Be careful when removing you don't bend up the Float, etc. I replaced the Fuel Cutoff Check Valve while I was in there because you cannot get at it without dropping the tank again, and for $12, why not get another 25 years? Part #7738026010
9. Remove the Filler neck components. I restored all these with a wire wheel brush, rust encapsulator and Chassis Paint and new fuel overflow check valve. New hoses as well.
10. Getting ready to put tank back in, BUT, need to figure out a way to replace that strap I messed up drilling out.
It looks like I can only attach 5 images, so will continue in a Part 2 thread.
Process:
Remove Passenger Seats to access port and see if leak may be from failed gasket or fuel lines. Not the issue.
2. Moved on to inspecting outside of tank with bore scope. confirmed leaking gas. (sorry no photos of this scope shots)
3. Time to remove tank. First Drain the Tank from the Drain Bolt. Auto Fuel is about 6.5 lbs per gallon so even 10 gallons will add 65 lbs to the Drop. Start with removing the 2 bolts that hold the fuel straps together. If lucky, with enough Kroil and heat, bolts will come out without snapping. Breaker bar with swivel head did the trick on all but one. The one that is on driver side closest to the front had to be drilled out. If I had known the future problem that specific bolt would cause (partial body lift), I would have gone slower and more carefully. So those doing this job, be particularly careful with this bolt. If it snaps and you ruin the thread on the Strap Nut drilling out the bolt, and you want to replace that small strap, you will need to lift the body off frame to back the bolt out holding it to the body!
4. Ok once strap bolts are removed, you can loosen the Hose Clamp from filler tube and the pinch clamp from vapor tube towards the back of the tank.
5. Remove the gas lines from the top of the tank through the access port to "free" the tank from the rest of the truck. (see image above)
6. Now, I was able to jack the front of the car up, and sneak the tank out the front without dropping the drive shaft from the back. BUT, knowing now that in order to get it back in easily, you really should remove the drive shaft in the rear and suspend it out of the way (leaving the front attached is fine) with bungee cords, I would have made my life easier just to remove the drive shaft in the first place. Make sure to remember to mark the shaft and flanges with white out or paint so re-align for proper harmonic balancing retention.
7. OK, now the tank is finally out! My neighbors wonder about the new Garden Ornament...
8. Remove all the fuel sensor components from the center of the top of the tank. Be careful when removing you don't bend up the Float, etc. I replaced the Fuel Cutoff Check Valve while I was in there because you cannot get at it without dropping the tank again, and for $12, why not get another 25 years? Part #7738026010
9. Remove the Filler neck components. I restored all these with a wire wheel brush, rust encapsulator and Chassis Paint and new fuel overflow check valve. New hoses as well.
10. Getting ready to put tank back in, BUT, need to figure out a way to replace that strap I messed up drilling out.
It looks like I can only attach 5 images, so will continue in a Part 2 thread.