66 fuel gage wiring

[Richard E.]

Is there any resistance check or voltage check that can be made at the wires which connect to the tank sending unit if the wires are disconnected from the tank sender and an ohm meter or volt meter is placed either across the leads or from either lead to chassis ground? I realize the ignition would be on for a voltage check and off for a resistance check. (The tank sending unit that was removed was bad.)

I would like to know that the circuit (at the tank end) is ok before installing and wiring the new tank sending unit. Should I first try connecting the wires with the sending unit out of the tank to check operation?

Thank you for any suggestions.

[Richard M.]

Re: 66 fuel gage wiring

Richard,

Yes, I would just connect the sender to the wiring to verify operation. Just make sure you also add a ground lead from the sender cover to chassis ground to complete the circuit. Then you can swing the float to check the gauge.

In the archives somewhere there are some links to test & repair of the fuel gauge and senders also. John Hinckley wrote up a nice one so try searching his name too.

Rich

[Joe R.]

Re: 66 fuel gage wiring

Try this John Hinckley article:

http://www.lbfun.com/warehouse/tech_info/gauges%20&%20instruments/MidyearFuelGauge.pdf

Joe

[Ronald L.]

Re: 66 fuel gage wiring

Richard, John's article is invaluable - but---

Check your new sender for 0 - 90 ohms resistance, zero down or empty, and 90 full up.

All the made in china versions I found were wrong in their readings and that you will never be able to correct through any type of ad-on resistor because the resistance is already too high. Easier to get a correctly reading unit.

It was only a NOS and or a very expensive older Delphi unit that read correctly...

[Richard E.]

Re: 66 fuel gage wiring

Thank you all for the helpful information. I will continue my circuit check out. As a side note I have a Delco sender (came in a AC Delco labeled box) GM #19180447 , ACD #FLS1111. The Delco label actually says "made in China". The resistor measurements are 90 ohm at full and 0 Ohm at empty, seems right on. The float is a yellow color & the filter bag is green for what its worth.

Thanks again.
Rich