C2 Fuel quantity sending unit

[Dwight P.]

I replaced my fuel tank about a year ago (Quanta Products)and the tank came with a new sender which I thought would satisfy NCRS judging criteria.

During the last NCRS Regional at Waco my car was docked points for not having the correct sending unit. Judges said the unit must have the AC Delco stamp on the bottom of the unit.

Are original AC Delco senders available through GM? Are AC Delco senders available through after market suppliers?

I still have my original sending unit but it is very "CRUDDY". Does anyone rebuild the old units?

Thanks,

Dwight

[Gerard F.]

Re: C2 Fuel quantity sending unit

Dwight,

Take a look at this post:

https://www.ncrs.org/forum/archive23.cgi?review=191098

Save your original no matter how cruddy. The originals are much more rugged then the repros. There is lot's of other posts in the archives on this subject.

They can be repaired but I'm not sure that anybody specializes in them. If you can get 0 to 90 ohms between the two ungrounded leads with the float up to down, then it is just a matter of cleaning them up.

My experience is that the repros last about a year.

Jerry Fuccillo
#42179

[Stephen L.]

Re: C2 Fuel quantity sending unit

Can you be more specific on "cruddy"? Its amazing what a bead blaster can do to clean up a part. Did the unit still work giving a tank level reading?

[Dwight P.]

Re: C2 Fuel quantity sending unit

Steve:
Yes the unit worked....but the car was stored for about 13 years, and fuel was not drained from the tank. So when i began to restore the car the entire fuel system was very coroded and I assumed that a new tank and sender was necessary.

I will try to find a "blaster" and see what comes out from under the corosion. Then I will test it and reinstall it if it works.

Thanks,

Dwight

[Dwight P.]

Re: C2 Fuel quantity sending unit

Jerry:

Thanks for the info. I will try to clean up the original, hope that it tests OK and if it does I will reinstall it.

[Gerard F.]

Re: C2 Fuel quantity sending unit

Dwight,

Don't beadblast the variable resistor part of the sender. If it's not giving you the right ohms readings, carefully take the variable resistor cover off and clean the contactor and the resistor windings. Look for any broken windings, that's when it's shot.

Jerry Fuccillo
#42179

[John H.]

Re: C2 Fuel quantity sending unit

Here's an original, just out of the beat-up old AC box, never been installed; you can see the "AC" stamped in it, plus an alpha code and several small inspection stamps between the terminals.

[Gerard F.]

Here's the repair on my fuel sending unit

The original is in front with the repro in back. I had to solder the band lead on the top of the variable resistor, and splice the bottom lead. The only thing I used from the repro was the little filter sock for the fuel line.

The variable resistor on the repro is completely different than the original and not interchangeable. It is a lot cheaper design.

The original now works fine but I don't know for how long.

Jerry Fuccillo
#42179

[Dwight P.]

Re: Here's the repair on my fuel sending unit

Jerry:

Thanks for the picts and info. This project will be interesting for me...I am treading into new territory...wish me luck.

Dwight