Fuel gauge problems

[Cobra427]

I have an L3560 hstc so the fuel tank is under the cab. My problem is the fuel gauge stopped working. When I turn the switch on it goes to full and stays there. I am trying to find out if there is a ground problem or fuse blown but I don't have a wiring diagram so I don't know where the ground or fuse is. At the back of the tank I can see a 90 degree metal tube connected to the tank but I don't see a wire. If anyone here has an idea how to diagnose this problem I would appreciate the help. Thanks for any suggestions
s

 

[Dave_eng]

I enlarged this WSM image to help you see where the sensor is located.
First check that a wire has not been pulled off.

Edit: adding more info

Dave

 

[Cobra427]

Thank you sir, very helpful and I appreciate the help...

 

[PoTreeBoy]

I have an L3560 hstc so the fuel tank is under the cab. My problem is the fuel gauge stopped working. When I turn the switch on it goes to full and stays there. I am trying to find out if there is a ground problem or fuse blown but I don't have a wiring diagram so I don't know where the ground or fuse is. At the back of the tank I can see a 90 degree metal tube connected to the tank but I don't see a wire. If anyone here has an idea how to diagnose this problem I would appreciate the help. Thanks for any suggestions
s

Since it goes to full, it is getting power. If the sensor is good, there's most likely a short between the gauge and sensor.

 

[GreensvilleJay]

if the guage reads 'over full', then either the sensor is shorted to ground, or the wire from it to the guage is.

 

[bambam31]

The fuel gauge on my L3800 was stuck on full for 5 years. It just started working this past Fall.

 

[Cobra427]

Since it goes to full, it is getting power. If the sensor is good, there's most likely a short between the gauge and sensor.

Thanks for your reply. I am not much good with a multimeter, is there another way to check if it is a ground?

 

[PoTreeBoy]

Thanks for your reply. I am not much good with a multimeter, is there another way to check if it is a ground?

Pull the connector off at the sensor. If the gauge reads empty, the sensor's bad.
If the gauge still reads full, pull the connector off at the dash (may be hard to find without a diagram). If the gauge reads empty, there's a short in the wire. If it still reads full (not likely), there's a problem in the panel.
Looks like it's a yellow wire.

 

[Cobra427]

Pull the connector off at the sensor. If the gauge reads empty, the sensor's bad.
If the gauge still reads full, pull the connector off at the dash (may be hard to find without a diagram). If the gauge reads empty, there's a short in the wire. If it still reads full (not likely), there's a problem in the panel.
Looks like it's a yellow wire.

Thank you again, I will try that tomorrow...

 

[dlsmith]

The fuel gauge on my L3800 was stuck on full for 5 years. It just started working this past Fall.

Yep, sometimes if you ignore a problem long enough, it goes away.
But not very often, usually it just gets worse.

 

[massahosa]

I have an L3560 hstc so the fuel tank is under the cab. My problem is the fuel gauge stopped working. When I turn the switch on it goes to full and stays there. I am trying to find out if there is a ground problem or fuse blown but I don't have a wiring diagram so I don't know where the ground or fuse is. At the back of the tank I can see a 90 degree metal tube connected to the tank but I don't see a wire. If anyone here has an idea how to diagnose this problem I would appreciate the help. Thanks for any suggestions
s

I am discovering that it is important to keep fuel tank full when storing tractor for long periods of time. It took 20 hours of use for my guage to start registering above 50% when tank was actually full. I believe oxidation is the cause

 

[GreensvilleJay]

or it could be mechanically binding ( 'stuck') or the float is 'heavy' (saturated with fuel )