Fuel gauge not working

avi8or3117

Seaman Apprentice
Joined
Dec 12, 2011
Messages
31
Hello,

My fuel gauge stop working recently, any suggestions on how to trouble shoot it? Is there some sort of electrical/resistance test I can preform on the sending unit or the gauge? Any way to figure out if it's a bad gauge?

Thanks for any pointers.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Fuel gauge not working

Most sender/gauges are 33-240 ohm.

First, check you have power and a good ground at the gauge. Then check the sender is also grounded well. Short the sender wire to ground, the gauge should peg full, with the sender wire open it should read empty.

If the gauge checks out and the wiring is good, then it's the sender.

Chris......
 

GlastronNWGA

Cadet
Joined
Feb 18, 2012
Messages
12
Re: Fuel gauge not working

definitely check connections closely! Mine had quit this spring as well. upon investigation, the ground wire was still attached at the sending unit terminal, but wasn't tight and had poor connection. I love easy fixes.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Fuel gauge not working

This must be post # 100 of this diagram and troubleshooting technique: SEARCH works great!

1) Do you have +12 votls at the "I" (ignition) terminal on the gauge with the key on. YES or NO.
2) If no - fix it. If yes, go to 3.
3) With key on, MOMENTARILY jump the "S" (send) terminal on the gauge to ground. Did the gauge peg FULL? Yes or No. If no, verify the gauge has a good ground. If good, gauge is bad (highly unlikely).
4) Turn off key. Disconnect the pink wire at the sender. Measure resistance from threaded terminal to metal shell of the sender. Depending on the amount of fuel in the tank it should read 33 ohms full tank, 109 ohms, 1/2 full, and 240 ohms empty. Sender is OK if these readings are reasonably close. Sender is bad if it reads open circuit or readings are way different. If readings are ok, go to 5)
5) Verify the metal shell of the sender has a good ground. If ok then the sender is fine.
6) If you did everything as directed, then the only possiblity is a bad (open) pink wire between the sender and the gauge. Fix it.

Gauge-SenderWiring.jpg
 

avi8or3117

Seaman Apprentice
Joined
Dec 12, 2011
Messages
31
Re: Fuel gauge not working

Silvertip
"Measure resistance from threaded terminal to metal shell of the sender"

What is the metal shell of the sender? Are you referring to the metal top of the fuel sender?
Thanks
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Fuel gauge not working

The piece with all the moutning screws in it.
 

avi8or3117

Seaman Apprentice
Joined
Dec 12, 2011
Messages
31
Re: Fuel gauge not working

Thanks for the help guys! Will troubleshoot this weekend.
 
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