fuel sending unit
 

Does anyone know what the oms resistance rating is on a 1938 ford gasoline fuel gauge? I have bought a new one for a tractor that looks like it would work but the gauge reads too high. I can install a gauge made for the sender but would like to use the 38 gauge.

Re: fuel sending unit
 

The heater coil in the sender itself is around 2 -3 ohms. There is a second wire wound resister that measures 8 -9 ohms. If the contacts (points) are corroded they would show a high resistance.

Re: fuel sending unit
 

Jseery Thanks again for your help. The problem is that the gauge registers too high on the new sender as well as the one from Macs (which is also a new unit) both show one half when float is all the way down and needle bottoms out way past full when the float is raised all the way up.

Re: fuel sending unit
 

Ok, got ya. The gauge really doesn't have an ohms reading per say. It should be in the same ball park as the sender, but not sure that tells you anything. Have you checked the gauge with a D-cell battery? 1 1/2 volts should give you 1/2 scale reading.

Re: fuel sending unit
 

No didn't check it. Good information. Will advise later . Thanks

Re: fuel sending unit
 

There is a lot of info on this site about King Seeley type fuel quantity systems with basic diagrams. They don't work like the ones that use rheostat type sending units. Some of the aftermarket repro senders will make them function but no one makes a rheostat type that will match the King Seeley gauge very well for accuracy. You either make do, find a decent OEM type sender, or change the indicator to match the repro sender.

Re: fuel sending unit
 

Have you tested it prior to installing to see if you could get the full range? You may only need to bend the are to correct your problem.

Re: fuel sending unit
 

Just got done removing gauge and testing it as instructed. Gauge registered between one half and three quarters.Does that mean to you that gauge is alright?

Re: fuel sending unit
 

Frank
Yes i did, checked the whole range.

Re: fuel sending unit
 

Rotorwrench
Thanks for the tip i will check it out.