gas gauge help

joebuck · Post by **joebuck** » Tue Jul 23, 2013 10:46 pm

On my 52 m38 I just bought the gas gauge does not work. I bought a new sending unit and installed. Gauge still reads empty when full. Sometimes it will bump to 1/2 full when full. Is my gauge the issue now? Anny advice? Thanks

Post by **wesk** » Tue Jul 23, 2013 11:17 pm

Search these forums for that problem. It has been discussed many times.

The Army published a troubleshooting guide just for the instruments. We have it loaded free on the downloads page:

http://willysmjeeps.com/downloads/instruments.pdf

Follow it step by step.

Most important thing to remember when working gauge problems is grounding. The gauges housings must be grounded to the dash to work and their senders must be grounded to the chassis/body to work. Dirt, corrosion and paint on these grounds will give you a lot of grief.

oilleaker1 · Post by **oilleaker1** » Wed Jul 24, 2013 5:49 am

Grounds can drive you nuts to say the least. I've had good luck on several of my jeeps getting the fuel gauge to work by running my own ground wire from a fuel sender screw to one of the seat mounting bolts or rear tank hold down bolt. You can test your sender by removing it and hooking it up and grounding it with a jumper wire. Then you can raise and lower the float. Don't make any sparks near the fuel! The intrument panel needs to be grounded well for some of the gauges to work and if you want to, you can run your own ground wire to the back of the gauge mount bracket itself if it helps. I'm doing this as we speak-------fun fun. John

joebuck · Post by **joebuck** » Wed Jul 24, 2013 6:23 am

Great help guys! Sender unit I noticed was seated with double gaskers? May be the culprit. Thanks again

joebuck · Post by **joebuck** » Wed Jul 24, 2013 7:43 am

Its just about to whip me. Hookedd a ground up to no avail. When unplugged, unit shows Full when plugged up. Unit shows 1/2.

Post by **Ryan_Miller** » Wed Jul 24, 2013 8:06 am

Joe,

The grounding on the fuel sender is a problem. I had mine working great and 6 months later it is finicky again.

Did you run a ground wire and also make sure the contacts with the wire and sender/jeep body are clean of paint/rust.

They are very tempermental.

Post by **wesk** » Wed Jul 24, 2013 8:43 am

More importantly have you followed the step by step troublesdhooting guide yet? Or did you just check the ground and repost the problem?

joebuck · Post by **joebuck** » Wed Jul 24, 2013 1:15 pm

Good point Wesk, i did not..Last 24 , i was deep into the woods at camp and internet spotty. NowI am at the office now and will sit down and read your suggested reading... thanks for the help

ServiceManual · Post by **ServiceManual** » Fri Jul 26, 2013 12:30 pm

Joe, I ran a cross this article that might help with your gas gauge problem. Not sure if your still running 24V but if not then at the bottom of this article it describes common gas gauge problems while converting. Good luck.

http://www.vintagejeepparts.com/electri ... ersion.asp

joebuck · Post by **joebuck** » Fri Jul 26, 2013 2:27 pm

Thankd SM. Mine is till 24 but that was a good read.