full tank only reads a quarter tank.

[84cucv1ton]

contacts are clean. still cant get it.. what am i missing? can a fuel gauge go bad.?? thanks

 

[Barrman]

The -20 manual has about a page devoted to fuel gauge repair and diagnosis. Basically, unplug the lead at the tank. Turn on the key and see what happens. Ground the lead, turn on the key and see what happens.

Open should be way past full while grounded should be below empty. If yours does that, then you either have a bad sendor or a bad sendor ground. If it doesn't, the tm says you need a new gauge if you have checked everything else.

 

[Dave Kay]

Time to replace the in-tank sender I would think. They do become worn and resistance makes them read wrong.

 

[Pops506th]

Sometimes the floats will become fuel-logged and will read much lower than normal.

Either way you look at it, you've got to drop the tank to repair.

 

[combat32]

Good info, I was gettin ready to explore the -20, mine reads 3/4 sometimes, 1/4 after I fill up, and somewhere around E when it gets down to 1/2 tank.

 

[Barrman]

Mine read acurate for a month last fall. Then one fill up when I was down to 1/4 tank (23 gallons added). It only went ot half tank. It worked on the reduced range scale for a few months. I hit a nasty unseen speed bump and it went to 3/4 with a full tank and read accurate for a few months with 3/4 as full. Now it is back to the E-1/4 scale. I have another sender, but we are just too darn hot to get much work done outside. Wednesday we had a high of 97° and I thought it was almost comfortable out. Back to 105° today and hiding in the a/c.

 

[overkill375]

I think there is a little black magic in getting CUCV fuel gauges to work

 

[Dave Kay]

I think there is a little black magic in getting CUCV fuel gauges to work

Not really black magic, I've redone truck fuel tanks couple times now and the sending device is simple; a sliding 12V scale that reads resistance--- that's it. When they become worn or corrode you just have to replace them. Unfortunately, that requires pulling the fuel tank

 

[M1008driver]

I would try 2 cans of SeaFoam on a full tank first. Maybe it will clean up your problem.

 

[84cucv1ton]

what will seafoam do?? thanks

 

[M1008driver]

It cleans up the varnish that develops with fuel.

As a fuel system additive, Sea Foam® will clean carburetors, fuel injectors, clean carbon, gum and varnish deposits, add lubricity to fuel, stabilize fuel for 2 years and control moisture.