After troubleshooting why the fuel gage on my '87 TPI IROC didn't work, the reason became obvious when the fuel sending unit was removed, failed the "0-90 ohm test" and taken apart -- the very thin wire inside where the sending unit arm sweeps was broken in several places, as shown in the attached photo.

Rather than spend a bunch of money, I'd like to repair the unit and need help to answer the following questions:

1. Is the wire a special kind of resistance metal, or just bare copper.

2. Is the wire wound in a certain pattern?

Thanks for any help!

 

The wire is wound in a certain pattern to the best of my knowledge (which doesn't mean a whole lot) but, the sender wire/piece has not change since at least '72. All GM gauges up to 92 use 0-90ohm resistance for the gauge reading.
My friends '72 truck had the same fuel sender (though, different float arm obvoiusly) as my '91 camaro.
*edit.. I know there is a little more detail about changing it but, I can't remember just at this point. The fiberglass washer that is on the outside of the case and how it is attached is almost a 1 time deal only.

 

I can work around the fiber washer .... but need to know the type of wire, size and winding pattern. It appears as though the two ends of the wire terminate at the plastic piece where the fiber washer is.

Tim? Trickster? Any input from your archives on this very small and quite expensive item?

 

Since the 0-90 ohm resistance piece in that little metal capsule appears to be so common, perhaps I could obtain just that part from one of the manufactures.

Anyone have any leads on what companies produce the fuel sending units?

 

My friend and I just finished fixing a sending unit and found the best (cheapest) solution in the junk yard. We tried to find new replacement parts, but not even the dealer offered anything. On my friends sending unit the arm that pivots across the wrapped wire was broken.

We took an ohm meter to the junk yard and just tested GM sending units similar to his and when we found a good one we pried it off the pick-up tubes with a screwdriver. With a little J.B. Weld (supposed to be fuel safe) we attached it to his sending unit and everything now works great. Total cost of repair $2.50.

A local salvage yard wanted $130, the cheapest new/reman. we could find was $160 and I believe autozone is well over $200. If you have a local yard you can save yourself a lot of money.

 

slow91camaro -- Unfortunately, the wrecking yards around here don't stockpile sending units on a shelf ... each one has to be taken out of the car and on 3rd gens thats' a hassle.

Unfortunately, nobody here seems to know the dimensions and type of resistance wire or how it's wrapped on the band, sigh.

I'm considering buying a cheap $20 replacement such as the one below and cannabilizing the 0-90 ohm resistance band.

 

Your telling me. . .. We pulled two out of thirdgens before we realized that our local yards do stockpile the sending units. Just about the only cars that still had the tanks in them were thirdgens and only because the guys who prep the cars (drain all the fluids and salvage good tires and rims) know they're too much work to remove and just stab a hole in the tank instead.

You don't have to pull them to test them, but even if they test well you may get them out only to find they're a different style than what you have. That is exactly what happened to us with both thirdgens, but then we fortunetly learned of the "magical stockpile."


If we'd known you could get new parts for $20 we never would of bothered with the junkyard! That definetly seems like the best way to go. Good luck.