fuel gauge sending unit

As anybody repaired a sending unit? My ford tractor has one that is bad and they are expensive and looking at it seems like it could be fixed some how because it is just a ground. Anybody ever fixed one?

I've tried to splice them but wasn't ever very good at it, I didn't have the patience grrrrrrrr

You're thinkin right, they ARE NOT rocket science, merely a wire wound variable resistor to frame ground with the resistance dependent on where on the winding the float contactor is in the tank level.

Give it a try and remember the resistance of the sender has to match the resistance the gauge was designed for. Perhaps 0 to 30 ohms or 0 to 100 or whatever???

John T

Boy, that makes me feel better, for John T to say he was unable to do it. Tried one for a cat 315 excavator not long ago. All it needed was just that winding repaired but could not get it to work. Cat parts are not cheap. Might check a junk yard but chances are that 50 year old unit is going to be bad in the one in the junk yard also.

JC Whitney sells universals and they are cheap. Their gauge is no good 'cause it can't take the weather exposure but the senders, being inside the tank, work out OK. I think $30 will get it done.

I used to work for a major company that made fuel senders. Most are just resistance wire wound around a form and buffed on one side to remove the insulation where the wiper goes.

If the wire is broken, your chances of fixing it are not so good. But if the problem is a build up of varnish on the coil, you might be in luck.

I "repaired" the fuel sender in my 1985 Toyota Corolla by gently cleaning off the accumulated varnish with carb cleaner and a soft toothbrush. Too much carb cleaner and you will dissolve the insulation that separates the wire turns.

If you remove the sender from the tank and measure resistance from the terminal to the chassis you should see a change. There are several standards, but I beleive the Ford senders were Stewart-Warner standard ~40 Ohms at empty and ~240 Ohms at full. The resistance should be between these two values with no dropouts end to end.

By visually inpecting the card and wiper while measuring the resistance, you should be able to isolate the problem quickly. Remember also to check the float.

If you need more help, drop me an email. I would be happy to help you work this out.

Cliff(VA)

When I was younger and a used tractor dealer I had patience to fix small precise tedious jobs like solder a fine wire HOWEVER I lost my patience and would end up trashing it now lol

John T

I put one from JC Whitney on my 35 Ferg. many moons ago and it is fine. At that time about fifteen dollars. TDF

Thanks for all the advice I am going to try and fix it,what have I got to loose? On inspection I will see if any wire is broken and then try to gently clean the wires and that might fix it,looks like it will be a while before I can get to it but will give it a try Thanks

Might be worth having it repaired.
sending unit repair place

(quoted from post at 17:42:12 11/27/13) As anybody repaired a sending unit? My ford tractor has one that is bad and they are expensive and looking at it seems like it could be fixed some how because it is just a ground. Anybody ever fixed one?

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Vintage Ford (trucks/cars) not sure what a tractor would be but spec its the same...

low 76 ohms
Mid point 23 ohms
High 9 ohms

Logic would tell me if it read around 76 ohms ohms the rheostat is good and the float is bad are theirs no fuel in the tank...
If it has a brass float they are known to go bad... They are still available new from any Ford dealer for around $10...