Removing old fuel sender

[aipri]

Hey guys, I am installing the DMCH replacement fuel sender, and was just wondering if anyone had tips on removing the old one. I am definitely the first person to set on eyes on this thing in 30 years and it is in there good. From what I've seen you need to twist off the rubber top first? Mine does not seem to be budging but before I go crazy on it I wanted to make sure I was doing it right. This car scares me and I am afraid to try anything without researching first! I did some searches but couldn't find any step by step instructions. I know on paper it's easy but I just don't want to break anything.

[Jack]

I know its "plastic to plastic".
So it shouldn't be seized.
I put on a pair of good leather gloves and turned it.
Mine was tight, but I was able to get it once I put leather gloves on.
If it had been any tighter I probably wouldn't have been able to get it by hand.
By hand I mean I used both arms, 'locked" my figures to it, and turned with my forearms.
This was done from the passenger side leaning inside the "trunk"
Does the old unit work at all?

[TTait]

The less gas in the tank the easier this will all be. If its almost empty already you could start by disconnecting the fuel feed line (not the return) where it connects to the hard line, extend it, and then run the extension into a gas can. Turn the key to run, (but not start) - wait 2 seconds - and back to off repeatedly until it pumps out all the gas, or jump the rpm relay to make the pump run continuously.

If the whole thing is coming out, remove the large hose clamp and then you should be able to wiggle the whole assembly loose. It will come up far enough that you can disconnect the fuel line from the base of the pump, and then you can set that aside. At this point you will have a view into the tank to remove your baffle assembly and pickup filter. Pretty straightforward.

Then disconnect the fuel lines, and the electrical harness, and you are good to go.

For the fuel sender unit, unplug the wires from the harness (about 12" from the sender) and unscrew the cap holding the sender down. If its tight you can use a screwdriver and hammer against the ridges, or try a large channel locks.

If your fuel sender was still working well, and you don't need it anymore, send me a pm - mine is a little flakey.

[aipri]

Thanks for the replies guys, now that I know for sure it needs to be twisted off I will try some elbow grease or clamps, etc.


If your fuel sender was still working well, and you don't need it anymore, send me a pm - mine is a little flakey.

The sender is shot, and just by moving the wire to disconnect it the connections on top snapped off, so I doubt you would want it lol

[DeLorean03]

Pliers like these have saved my butt a bunch:

21968

Instead of opening them up and trying to get them all the way around the sender (circumference), I'd open them up and lock them down on top of the plastic cap (diameter). Might not be as strong a grip as going all the way around, but it would definitely give you some decent torque to break free the 32 year old original.

[aipri]

I just got it, I used the screwdriver + hammer method to get it moving then it came off easily. I have a follow up question though, how long should it take after the install for the fuel gauge to show a correct reading? Do you have to take it out and drive a bit?

[TTait]

It should show the proper setting within about a minute I'd think.

If you got the houston unit, they are pretty bad for this. There is a screw in the bottom you can remove, or loosen, to allow fuel to go in and out faster. In general the houston units I've tried won't show more than 3/4 tank. Ive sent two back and am waiting now for Josh to make his new one.

[aipri]

It's actually a DMC UK model. I didn't order it myself, the PO gave it to me with the car. I ran the car for a few minutes and its staying at 1/4 of a tank, which I know isn't right because I only have about 40 miles on the car since last filled it. I am going to drive it around a bit and see if it catches up I guess.

[Rich]

I am going to drive it around a bit and see if it catches up I guess.

That's a good start. If it comes up to Full sometime during the drive it means the float wasn't free for some reason. The DMCUK sender does use a float?

If the problem persists then jumper a solid, reliable ground wire to the ground wire out of the fuel sender. When that makes it work then renew the ground connection, a common problem at various locations on "dusty" D's like yours.

Beyond that you have to look upstream toward the gauge cluster.

[aipri]

So I took the car out and the gauge stayed at 1/4 tank, but I did notice it moving slightly up and down when doing things like going up or down a hill, or coming to a stop/accelerating. So I guess that means it is working, but just not accurate for some reason?

[TTait]

If it looks like this:

http://store.delorean.com/p-6566-fuel-tank-sending-unit.aspx

Then its a houston unit imported to the UK, then back. If that is the case then you will find a phillips head screw in the bottom, loosen it and put it back in the tank, see if the level comes up on the gauge. If not, remove the screw entirely and see if that does it.

[Rich]

So I took the car out and the gauge stayed at 1/4 tank, but I did notice it moving slightly up and down when doing things like going up or down a hill, or coming to a stop/accelerating. So I guess that means it is working, but just not accurate for some reason?

Do you want to find out?

Take the sender out. Plug it in and turn the key to ON. If it has a float push it to various positions and check the gauge.

If the gauge then shows good readings then you know the float isn't following the fuel level.

If the gauge is still at 1/4 when the float is all the way up/full then you either have a bad sender, a bad ground or a bad gauge/wiring. Don't go putting a new sender in til you check the ground and do other simple troubleshooting. A new sender should work fine.

Did the old sender work the same way?

[krs09]

If its the one tait shows I just installed mine last week and it worked beautifully (thanks dave p). My gauge was stuck a 12oclock since I got the car. Once I checked the sender I noticed the ground wasn't connected to the sender at all. So I checked the wiring, popped it in and ran to the driver seat to turn the key and behold the gauge started to move for the first time! It slowly dropped to just below 1/4 and stayed, I put 2 1/2 gallons of gas in and it read perfect. The unit is great for me so far

[aipri]

The old sender was completely random, when I first got the car it seemed to be working and dropping as I drove. When I refilled for the first time it didn't move. Then it randomly moved up at one point, then back down later. I knew it needed to be replaced so I didn't monitor it too closely. I am going to try what you guys said though and loosen the screw, because that does appear to be the model I have. It just says DMC UK on the top of the unit, so I wasn't sure if they had a different model than DMCH.

On a side-note this is the first time in my life I hated living in NJ where all gas stations are required full service. Every time I pull up to a gas station I have to see the dumbfounded look on the attendants face, and then get out, pop the hood and show him where the gas cap is. I'd rather just pump it myself. I'd almost rather cross the bridge to PA except that the price would me .25/gallon more.

[aipri]

So I pulled the sender back out but left it plugged in and turned the car on the gauge went down to E and the fuel light came on, so that appears to be working. I put the sender back in and the gauge went to in between 1/4 and E. Side note: I put about 60 miles on the car since the last time it was filled. So next I decided to try adding fuel. I went the gas station and the attendant put in 6/5 gallons before the pump popped and he pulled it out. The gauge is now inbetween 3/4 and half. So yeah that makes a lot of sense. Is it possible that the attendants aren't filling the tank all the way?

[Rich]

So I pulled the sender back out but left it plugged in and turned the car on the gauge went down to E and the fuel light came on, so that appears to be working. ...I went the gas station and the attendant put in 6/5 gallons before the pump popped and he pulled it out. ...Is it possible that the attendants aren't filling the tank all the way?

Good start. So you know the sender is giving an accurate "E" reading.

Recommend that you pull the sender again, leaving it wired up and make the float go all the way to the top/full position (push it or invert the sender) and see what the gauge does. Also with it out see if you can find any reason the float would hang up at any point in its travel - anything bent or misaligned?

Yes, it is possible that the auto-shut nozzle is shutting before the tank is full.