The Stovebolt Site Forums The Shop Area The Electrical Bay what does it mean when my gas gauge goes to empty?

except i am out of gas. i have switched out my dash insert and the gauge goes to zero when i turn the key on. it has a new under bed tank, sender unit. thanks, hr

Are you sure it's wired right?

You need to give these guys and gals more info about your gauge and setup. Some gauges use zero ohms to indicate a full tank while other use zero ohms for an empty tanks. So produce year, type of sender, gauge infomation, etc. and I'm sure the solution to your problem will be forthcoming.

The simple fuel gauge operation:
1) positive lead from ignition source to one side of gauge
2) second post of gauge goes to the fuel sender
3) fuel sender housing is grounded to fuel tank
which should be grounded to chassis
4) fuel sender varies amount of ground gauge sees depending
on amount of fuel



Fuel senders;
GM (0 to 30ohms) up to 1964
GM (0 to 90ohms) 1965 and up

Joe

On my 6v 1954 fuel gauges (I.ve tested several of them), when the positive lead from the ignition source is connected to the gauge, if I disconnect the wire to the sender, the gauge reads full. Just as it is described in the Shop Manual.

beltfed's point is is well made.

sorry i didn't let you know any of the info, who knows what i was thinking. 1963 chevy c10. the under bed tank and sender unit are from lmc truck. it was a little different than the ones i have ordered before like i have on my 64. it had a threaded post to hook the wire from the gauge to. this one had the ground wire but the post wasn't threaded so i just crimped on a connector. the tank is sopposed to work on 60 to 66 i thought. i switched out the dash cluster and thought that would fix the problem, but i don't know for sure if it's the gauge or not. i tried hooking up a 64 to 66 gauge i had around same thing.
it reads whatever then when i turn key on it goes to empty. my 64 does this it read 3/4 all time them when i turn on key it goes to proper location. soooo i am not sure if its the gauge or what. i also used a larger gauge wire to go to the tank, mabey that's the problem.

Larger wire shouldn't have any effect on the gauge. If you have a spare sender, use jumper wires and hook it right to the gauge by passing the wire harness, or better yet, take both gauge and sender to the workbench and try them out. Joe

i tried bypassing the fuse box and hooking up straight to gauge. i was just trying to avoid droping the tank. since this is a new tank/ sending unit i figured it was the gauge or something i done.

Is the tank or sender grounded? Try adding a ground wire from the frame right to one of the sender mounting screws. Joe

yep it came with a grounding wire and i attached it and made sure it's a good connection. the only thing that was wierd or made me thing i may have hooked it up wrong is it's different that the last underbed tank kit i bought. like i said the last one had a threaded stud for the wire, this one just had a odd nub on top. i am not sure what kind of connector it is supposed to have so i used a crimp connector. i am draggin' my heals on dropping the tank, busy painting the bed for now. mabey the light will dawn on what i did wrong. i was hopin' someone could tell me "oh if the gauge goes to empty when you turn on the key it's bla bla bla" . i was wishing for the lazy way out. hr

Your new sending unit may have a bad float and it has filled with gasoline and sunk.