Find the diagram pasted on the inside of one of the machines covers. Then trace out the gauge circuit. If you have a Ranger 250 GXT The fuel gauge should have 12vdc on terminals 1 and 3. 2 is the input from the sender in the tank.
Start /run switch must be in run. 12vdc starts at battery goes through circuit breaker and then start / run switch. Fuel tank sender should read 240 to 265 ohms empty and 20 to 35 ohms full. If your unit has a plastic tank, look for a ground wire from the sender to frame.
Always post the machine code number with questions on Lincoln welders.
That way we can pull up the right information for your welder and not have to guess.

 

Thanks, For your reply I will trace the gauge circuit out. I should have known better not to post without the code number which is (11117 on model K1725-6).. just in case you have any different information. Again thanks for your assistance...

 

checked the diagram in the owners manual for you machine. see the bottom right hand corner.
wire 210J is on three and 5L is on 1. all #5 wires are DC ground. wire 230 from terminal 2 goes to the gauge. Still need 12vdc on 1 and 3 at the fuel gauge. Sender Ohm value is the same.
Go to the sender and see if you have any voltage from the terminal to the body of the sender.
Run / stop switch must be in run. get a voltmeter and post the measurements at the gauge terminals. 1 to 2 and 1 to 3. run switch on. then measure the sender both volts and with switch off, the ohm value.

 

I measured volts from terminal to sender body at 2.78 volts and ohms from terminal to sender is reading 13.8 M ohms.. From gauge terminal 1 to 2 reading 0 volts and terminal 1 to 3 reading 12.49 volts...

 

Well, problem(s) solved with fuel gauge. First the fuel gauge itself was not working, and Second the fuel sender float had separated from the bar. New fuel gauge and a couple of new screws on the float and problem solved. At the least it answered my questions of some crazy Ohms readings I was getting.. Who would have thought there were two issues.. Thanks CCAWGC for your help with this issue. Would have been a bit more straight forward dealing with one problem, but hey it is what it is....