80 G fuel gauge repair help

[grabberblue]

Anyone have a tip on how to test and fix my fuel gage? it is connected but nothing has ever moved/ worked. What is the usual failure mode?
TIA
John

[randy]

John,

Remove the connector at the fuel tank. With the key on, you should read 7 volts accross the socket ( the side that disappears into the wire harness going to the guage ) And testing the tank sender, you should read:

Full = 6 to 10 Ohms

Half = 28 to 36 Ohms

Empty = 75 to 85 Ohms

[grabberblue]

Thanks Randy,
I did the tests and got no Ohm reading from the tank sender, so this must be the problem.
Does this sending unit come out like the petcocks? I never looked under there when I had the tank off.
Will I need to replace this unit or can it be repaired?
TIA
John

[DiverRay]

John;
The sending unit is held in place with 4 bolts, and seals with a large "O" ring. If you drain most of the gas from the tank, it's easy to pull the unit. Check for a broken ground wire, as it connects on the outside and can sometimes be pulled off the spade connector. Next I would try to clean up the sending unit, and retest on the bench. If it still won't work, I'm sure someone should have a spare you could pick up.

[skids]

It is more of a rubber gasket than an oring. If the connector at the tank is good, move the wires around near the location where they appear from the wireloom, while checking volts. In my experiences, the bi-metalic thing that deflects the needle in the gage, is subject to breaking at its base...and if this is the case, it will not go to just left of the empty mark when the key is off.

[QUOTE]Originally posted by DiverRay