Gas Tank Ground

[moparjack44]

I know, mine is a DeSoto, not Plymouth or Dodge, but this is something all should have in common.

How is the gas tank grounded to the frame/vehicle?

My gas gauge never goes past 1/2 full, and the needle flickers.

Jack

[TodFitch]

Two wire or one wire setup? If I recall correctly, one of the symptoms you can get on a two wire gauge with one wire missing is a max reading of half tank.

[moparjack44]

Actually the gauge is 3 wire.

Jack

[55 Fargo]

Jack, is there 2 wires at the gas tank sending unit, and 1 from this point as a ground wire.

1st things, make srue all of your connections and wires from fuel gauge to sending unit are in good clean condition.

Has your gauge always read like this?

How old is the sending unit, an old original, inside the sending unit there is a wire winding, if at the half way point the wires are frayed or broken, you can have inaccurate readings.

A lot of times if the gauge and sender are in good working condition, the wires and/or connections are the culprit.

You may have to pull the sender unit, and bench test it, or run some new wire from the gauge to the sender and see what happens.

DO NOT HOOK UP OR DISCONNECT WIRES TO THE SENDER WITHOUT YOUR BATTERY DISCONNECTED, AS A SPARK COULD BLOW UP YOU AND YOUR TANK TO SMITHERINES.

Norms Coupe knows how to bench test thses senders, hopefully he will chime in................Fred

['37 P4 Touring]

I know, mine is a DeSoto, not Plymouth or Dodge, but this is something all should have in common.

How is the gas tank grounded to the frame/vehicle?

My gas gauge never goes past 1/2 full, and the needle flickers.

Jack

You can add some grounds to be sure you are grounded. I added one at one of the sender mount screws to the trunk floor where the sender cover screws on and another at the tank outlet to the frame. For this one I used a tight fitting clamp and heavy wire to the frame. Now there is no question as to a good ground. You need to ensure the battery has a good ground also. I replaced both battery cables and added a heavy ground wire from the transmission to the frame. Good grounds eliminate a lot of problems on these old cars. I would take care of the grounds before tackling the sending unit.

Good Luck,

Jim

[moparjack44]

Thanks everyone. I will try your suggestions. Probably be end of next week before I can get back on it. I ordered new speedo cable, so I am going to wait until it arrives, and tackle both at the same time. I will let you know how it turns out.

I really appreciate y'all giving this old DeSoto guy some of your time. I promise not to abuse it.

Jack