Fuel gauge doesn't work

[pint4]

The fuel gauge on my 33 Buick doesn't work. I believe the sending unit is ok and grounded per tests done. Wiring from sending unit to gauge on dash appears to be good. How do I test the gauge itself? There are a couple of terminals on the back. The top one has one wire going to it and the bottom terminal has two wires. The gauge apparently is a two coil system. Does anyone know what wires go where? Maybe it is wired wrong. I am lost as to what to do. The needle is on empty and doesn't do a thing. Doesn't move at all.

Thanks.

Bob

[Leif Holmberg]

Why not bay a shop manaual on e-Bay for $16.And you can solve most of your Buick 1933 problems. Item number: 300144572974 Good Luck Leif in Sweden.

[pint4]

Thanks for the suggestion. I have a shop manual but not enough troubleshooting info in it. I need something I can follow step by step such as a test procedure.

Thanks.

Bob

[pint4]

If my fuel gauge is shot, does anyone have one for sale for a 1933 Buick?

Thanks.

Bob

pint4@new.rr.com

[Guest GP Gleason]

On the 1930s GM cars the top post was "normally" the hot wire from the ignition and the lower terminal went to the tank sending unit terminal.

The biggest problems with old gas gauges is usually a bad ground. The gauge must be grounded to the dash, the dash must be grounded to the body, the body must be grounded to the frame, the fuel tank must be grounded to the frame.

GM big cars sometimes had a butt connector in the wire from the tank sending unit to the gauge. Sometimes there were two! They would often get corroded and lose continuity.

Assuming you have made all those checks stated above and everything checks out then try this.

The tank unit test I use is as follows:

(assuming the gauge and wiring are in working order & body is properly grounded to the frame)

Disconnect the wiring to the tank unit at the unit terminal(s).

Remove the tank unit from the tank.

Install a jumper wire from the tank unit mounting flange to a good ground on the vehicle frame.

Attach another jumper wire from the end of the wire which was connected to the tank unit terminal and the other end of the jumper to the tank unit terminal. Allow the float to hang down (empty position)

Have a helper turn the vehicle ignition switch to the “on” position.

While the helper observes the gauge, s l o w l y move the tank unit float up (toward the “full” position).

The gauge needle should smoothly move from empty to full on the gauge.

If the needle jumps around or pegs or drops to empty during the full-range movement of the float then the tank unit must either be rebuilt or replaced.

Sorry to be so long winded!