DeLorean Fuel Pump Replacement

8/27/2005

Swear Meter Rating of 7: Overall nastiness, time consuming

When my car first arrived it had a hard time starting up. Long story short it was the Control Pressure Regulator. While trying to diagnose that problem, my fuel pump siezed up, thus confusing me further.  I had only put 14 miles on it since purchase. This was the first major fix I did on the car, and it turned out well.

First and foremost, disconnect the battery. Electricity + Gasoline = Danger.

To access the fuel pump area, open the trunk and remove the screws holding down the access panel closest to the windshield in the middle.  If your car is anything like mine, this area is a mess. My moisture cover wasn't even on the boot at all, and the clamp was clamping.. nothing. Start by disconnecting the power plug. The whole assembly can be removed at once but remember the hoses are connected to the bottom of the tank. Be prepared to get filthy at least up to your elbows. I peeked inside my tank at some rather NASTY gasoline and the deteriorated bits of my gas hoses.

Drain the gas tank.  You'll need a pump/siphon of some sort and a container. I got a neighbor to help with this. Again, NASTY. The gas was sort of a dark orange color.  It's not supposed to be that color. Once the tank was pretty empty I dabbed up the rest with paper towels.  It took a while to get it all and I'd recommend some chemical resistant gloves. The original baffle setup is bizarre. Metal spines keep down the baffle that fills with gas which is sucked through the little screen on the end of a hose that goes at several angles to the pump. A return hose drops gas directly back into the baffle so when you're low it doesn't die. I opted to replace this with a more direct approach developed by John Hervey  (www.specialtauto.com). The whole baffle system is held down with a nut attached to threads built into the tank.  Be careful removing the nut! The baffle can be pulled through the fuel pump hole - you have to sort of warp it but it'll come out. Inspect for breakage and clean it while it's out.

I also noticed some electrical hijinx while in there, my fuel sender unit had some creative wiring done to it, which I fixed. Soldering near a gas tank is a little scary. Anyway my original fuel screen was nasty and my whole tank was full of crud. Unsure of what else to use, I dabbed my rags with a little gas and swabbed out the inside of the tank. I took pictures as not to leave anything behind, and I'm glad I did as part of one of my shop towels broke off in there. When dry I vacuumed out most of the debris and felt it was clean enough. Removing the fuel sender unit helped quite a bit so I had room.

I assembled my new fuel pump setup as per instructions and installed it. If you're going to re-use your original baffle system (with new hoses I hope) just reverse your disassembly procedure.

The first picture is a peek at the straight-down fuel pump/baffle setup from John Hervey. The baffle bolts directly to the screw on the bottom of the tank and the pump boot holds it exactly in the right place. I also replaced the fuel lines going in and out of the fuel pump.  Make sure you get it right, as one goes to the engine and one returns unused fuel to the tank. I had to cut my old ones off, and the new ones had clamps for easy assembly. The 4th picture shows pretty much how it's supposed to look.  The boot cover is clamped around the boot so no water can get in there and everything's pretty cleaned up. I borrowed a gas can from the same neighbor as before and put in a few gallons of clean gas.

I reconnected the battery, and after a few tries... VROOOM! ... clunka-clunka-clunka-sputter-sputter.

Back to diagnosing my cold start issue!