The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Fuel Gauge Chevy C-10 / '66 Truck

Hi Friends, I recently bought a 1966 Chevy C-10 and the fuel gauge was disconnected. After connecting the wiring to the back of the gauge, the wire to the fuse block and cleaning the ground at the sender unit and turning the key to the on position, the needle went to empty. I checked previous posts regarding to the fuel gauge and sender unit and performed the differents trouble shooting with the jumper cable to ground the sender unit and fuel gauge but the gauge needle never moved again. The gauge has good ground, 12 volts at the cable that connects to it and 12 volts at the fuse in the fuse block. As per previous post the ohms at the sender unit should be 0-90 and mine is reading 241. Based on the ohms reading the sender unit is not working properly. Let me know if there is any other test that I should perform. PLease advise.

Thanks

You might try posting this in the electric bay

Ok, Thanks

The factory sending units and fuel gauges were 0-30 ohms, so you may have a non-factory sending unit of a different ohm range, than the factory fuel gauge. This problem is not uncommon. Do the ohm range test, through the float range on the sender, with your ohm meter. It should not exceed 30 ohms +/- a few ohms.

I removed the sender unit and it says 30 ohms at the level float. I tested again and now is reading correct from 0 to 30 ohms. I installed the sender unit again, tested it and it is reading between 6 and 7 ohm. I connected all the fuel system and gage its still going to Empty. Any recommendations?

Thanks

ground check!

Make sure the guage is wired correctly.

Hate to ask the obvious but are you sure there are at least a few gallons in the tank? my 65 would read empty well before the bottom of the tank

I checked the ground and the gauge still reads empty. I added more gas to the tank and the ohms at the sender unit increased. I removed the gauge, connected to 12V and ground, and the needle never moved. Does the gas fuse at the fuse block has power with the ignition key off? I think the gauge it's not working.

If your gauge reads full all the time( with the key on ) , that generally means you have a break in the wiring between the gauge and sending unit . If it reads empty all the time , generally you're looking at a short somewhere in the wiring between the two units . At least , that's what I've been told by people smarter than myself !

if you put 12v across the guage and it didn't move it's probably shot. measure the resistance of the guage out of the circuit, if it's zero it's shot.

Fuel gauge is working now. I found that the ground at the instrument cluster was bad.

Thanks all.

I had the same problem with my 64' and what I found that fixed it was replacing the wire between the units. Somewhere there was a break in the wire and as soon as it was done, I had smoke in the wire again and no more problems with the gauge. Hope you get yours taken care of and find what it takes to get it going again.
Tramp