Fuel Level Sender

[JTO]

Hi Folks,
I have a mysterious problem with my car's fuel level sender. The gauge reads normally on the upper half of the range but doesn't drop below the half full mark. The strange thing is that the fuel light works normally, e.g. the low fuel light comes on when there's two gallons in the tank. The gauge still reads half. What's up?

By the way I pulled the sender out, cleaned it, cleaned the contacts.
Thanks,
Troy

[911SCfanatic]

Got the same problem, however, my problem started after I replaced the fuel level sender gasket.

[jdowty3]

I have a similar problem and replacing the sender did not fix it. I think mine is a ground problem in the sender connector or a problem with the guage.

[thabaer]

Sounds like exactly what my SC was doing when I got it, I pulled the sender and everything looked OK there. I pulled the guage and found that it was sticky; cleaned it and never have had the problem since then.

[JTO]

So Charlie,
You suggest that the needle on the gauge may actually be hanging up? I'll also look at the electrical connections.
Thanks,
troy

[thabaer]

For some reason I started out blaming the sender, but the ultimate fix was popping out the left gauge assembly and doing a simple cleanup inside the fuel side.

This was 20 years ago, but ISTR the gauge was jamming in the lower half of its motion and the empty warning light was working because it triggered from a separate contact at the bottom of the sender ??

as always, YMMV

[kucharskimb]

i have the same problem on a 72 T. when i cut the power, the needle falls to zero.

thabaer, do you recall this being the case with yours?

any other have any luck cleaning theirs out?

thanks
matt

[morganb]

Mine did this, I believed the gauge and not the light and ran out of petrol. I replaced the sender and all is OK.

[JTO]

Mine indeed turned out to be a needle hanging up in the gauge. Once freed, it work normally.
Thanks,
Troy

[thastings]

I had the same problem , and last weekend, while cleaning my gas tank, I pulled the sending unit apart. Take the sleeve off the tank sending unit by removing the small nut on the bottom, and slide the the unit out. Very easy to do. I bet you will find the lower half is rusty and does not let the float drop down. A little bit of emery cloth or find sandpaper will solve the problem. DO NOT sand or break the guide wires. The float should slid up an down the rod.
Terry
Putting it back together takes all the time because you are trying to put that small rod thru the hole in the bottom without breaking the wires.

[Paulporsche]

If you tap on the gauge while it is reading higher than it should, and then the needle falls, then your gauge is sticking. Clean it as the others have said.

[jdowty3]

From those who have cleaned their fuel guage, what process did you use? I removed mine from the guage holder but was afraid to try and pry the needle off which seemed to be required to get any farther in to the guage unit. Has anyone sprayed one out with electrical contact cleaner\lube?

[72doug2,2S]

Bump

[KCPSG]

Originally posted by jdowty3
From those who have cleaned their fuel guage, what process did you use? I removed mine from the guage holder but was afraid to try and pry the needle off which seemed to be required to get any farther in to the guage unit. Has anyone sprayed one out with electrical contact cleaner\lube?

I just recently had taken my gauge apart and found that a pair of needle nose pliers did the trick for removing the needle.

[69Olive]

Because of the thin wires in the fuel sender, I cleaned mine by putting it in a jar of warm diluted Marine Clean (from POR-15). This removed all the gum/residue. Originally the float in my sender kept getting stuck when I inverted it. It was very smooth after the POR-15 treatment.

[72doug2,2S]

Not to hijack this thread, but has anyone here had clearance issues with the replacement tanks and senders. I had to hacksaw my replacement sender to get the sender to fit into the repro tank.

I couldn't tell whether the new sender would have worked with my old tank as I had dented the bottom from a road hazard.

[RoninLB]

fwiw.. there is a rubber gasket available.

['78 SC]

re: cleaning sender slider wires

I had very good results cleaing the wires and contacts using a swab wetted with lacquer thinner. The gummy deposits came off easily. Use a light touch to avoid stretching the slider wires.

[72doug2,2S]

To clarify, the sender tube was hitting the bottom of the tank. It wouldn't sit down.

[kucharskimb]

JTO
prior to fixing your gauge, when you turned off the key, did the needle fall to zero?