Re: Fuel tank cleaning/removal

[deloreanernst@xxxx]

(Moderator's note: It's essential that the battery is disconnected prior 
to the following)



Before you try jumping up and down on your gas tank, try this:

First, not to be too pessimistic, but sit your fire extinguisher at the ready 
nearby. Any collectible car should be equipped with one. There was a thread 
about it on the DML a few weeks ago. Also:
* Do it outside, preferably with a breeze blowing. The smell is overwhelming.
* Lay a fender blanket or similar over your fender since you'll have to use a 
step stool or shorty step ladder to climb into the trunk. Don't ding that 
fender! Or lean anything against it that you're climbing on.
* Be sure you get fuel resistant gloves. "Household" type playtex or 
whatever will disintegrate.
* Suction it thru the fuel pump hole not the filler neck. It's easier.
* Use a "kerosene pump" with a large stiff suction leg. It'll still take a 
long time, but the cheap siphons with the flimsy suction hose like an IV line 
are worthless. The tank holds about 12 or 13 gal full, as I recall. Even a 
nearly empty tank can pretty well fill a 5 gallon gas can.
* You can shine a light down the sending unit hole to see what you're doing 
in the pump hole with the baffle. I used a strong flashlight. I've seen the 
bulbs burst on too many drop lights... don't want to see it happen in a 
potentially explosive atmosphere!
* Rinse some acetone thru your fuel sending unit while it's still wet. It's 
probably sludgy.
* After you pump out all you can, use a clean, lintfree but expendable towel 
to mop out the inside of the tank. Careful... there's a wire-like structure 
in there. Don't beat up on it. Wring gas out carefully into a large metal 
pan, sludge and all. My long arm was TOO long and wouldn't make the bend 
going in. I used a stick and towel, wrist deep. 
* After you get the gas pumped out and wiped, let it sit overnight to air 
out, if possible. Then rewipe with the acetone.
* Replace any rusted components on the pump boot support.
* Check the wires leading from the pump. They may be kinked and brittle from 
heat and age. Replace if needed. The studs on the pump and connector loops 
on the wires are different sizes, so it's hard to get them reversed. 
* Wires seat in the 2 grooves on the front side of the boot, to seal better. 
* Check condition of boot bottom.. It may look great on top but be checked 
and deteriorated inside the tank. Check pickup hose too. Rinse pickup 
filter with acetone. Wipe carefully if needed to clean it.
* The return hose is held to the baffle by a clip, so it feeds gas to the 
inside of the fuel baffle.
* The picture of the baffle in the widely copied Service Bulletins has an 
error: it shows the smaller, outer baffle spring upside down. :( The short 
legs should face down, hooked into the lip of the lower baffle pan.
* Put the baffle nut back on finger tight, then carefully give an eighth turn 
with a metric socket or nut driver.
* Be sure the "tooth" in the sending unit engages the notch in the hole when 
you replace it.
* The copper seals should be replaced on any disconnected fuel lines. 
(You'll usually have them disconnected at the pump end, for boot replacement, 
or manueverability)
* The nut on top of the pump should be about level with the top of the fuel 
pump boot/collar/support, with the pump sitting level.
* The hoses feed toward the rear of the car, back, up and then over to the 
side.
* The pump cover seal is snug, but must fit in place or water will get in 
your pump and wreck it. If it's misshapped with age, replace it.
* Check the filler neck hose fort deterioration while you have the pump cover 
off. You can see the lower end of it.
* After it's reinstalled, (with the access cover still off, so you can 
inspect it,) fill the tank to the halfway point (not with your sludgy gas,) 
and start the car, carefully checking for leaks. Be sure the gas cap is 
closed snugly or the tank won't pressurize, and you might not see a possible 
leakage spot. Then try with a nearly full tank. 
* If you're satisfied with your handiwork, replace the fuel pump access 
cover, spare tire, etc. After you run through a full tankful, replace the 
inline fuel filter under the car, with its copper seals.
BTW, if you partially reassemble the pump after disassembling and examining 
it, to make it driveable while you wait for parts and a few free hours, be 
sure to replace the access cover, or your tools and screws in the trunk could 
wind up bouncing out all over the road. 
Hope that helps!

Wayne A Ernst
The New DeLorean Manuals Project