Well, as a few other people have had to do, I had to 'whip' the tank off my ZS a couple of days ago.
I use the word whip very carefully, as it's not as easy as you'd think!
If you're going to do this, make sure you have the following handy:
- 2x 13mm spanners for lock nuts
- Trolley jack
- Axle stands
- 4L parrafin to clean the tank out
- Dremel for cutting the fuel tank hangers if needed
- M8 threaded bar, for making new hangers if needed
- 4x M8 nuts for replacement hangers
- Big vice and 'manly' hammer for making the new hangers
- Pliers for removing pipes from the tank connections
Here we go...
1. Make sure you have only a little or no diesel left in your tank.
Jack the rear of the car up, and support with axle stands. I mounted mine underneath the rear trailing arm.
2. At the back end of the tank, you'll see the two hangers, with a pair of locknuts on each. Spray each with some penetrating oil, and attempt to undo the lower nut. If the nuts are free enough to move, start loosening them and lowering the tank down onto a trolley jack.
If not, then cut through the hangers with a dremel or equivalent, above the locknuts.
3. With the tank supported on the jack and lowered about 3-4 inches, remove all connecting pipework. Unclip the wiring to the fuel level sensor, the cable connection is on the rear subframe.
4. Lower the tank to the ground, and remove the fuel take-off system, being careful not to damage the fuel level sensor. Make sure this doesn't get any dirt on it, leave the assembly on a plastic sheet or equivalent.
5. Pull the tank out from under the vehicle, and rinse with parrafin vigorously. Once you're satified the tank is cleaned out thoroughly, replace the fuel level / fuel take-off assembly. Then place the tank on the trolley jack, and raise the tank until it is about 3-4 inches from it's resting level. Connect all fuel lines and the fuel level sensor wiring. Finally raise the tank the last few inches.
6. If you managed to get the locknuts off, simply re-tighten them up. If not, then cut approximately 200mm of M8 threaded bar, bend the end into a 'candy-cane' shape, and hook this where the original hangers were. Thread one nut up the new hanger, then continue to fit the tank as you would if you were using the original hangers. Make sure the tank is properly supported and tight.
New hangers, with nuts fitted:
7. Lower the car, add some diesel then loosen the bleed screw on the fuel filter. Pump the priming bulb until fuel bubbles out of the bleed screw, then re-tighten it. Start her up and away you go!
Of course, this job is a whole lot easier if you have a slave to help you with it...