Yeah wouldn't that be nice to have a magic self filling fuel tank seriously though the fuel gauge in my 86 Mitsi FK415 decided to creep back up to full while I was driving down to a job. When I jumped in the old girl the gauge was just over half and then crept up to full over a matter of 20 minutes or so. Anyone had this sort of thing happen, I am guessing it may be that the float in the sender is getting sticky and slowly creeping up because when I jumped back in the truck, after 5 hours of spreading gravel over a drive, the gauge read a little lower but crept up again. Spose I can just get a stick and check the fuel that way
fuel guage Yep, sounds like the sending unit. Some of them has an adjustable arm and if it gets loose, it may do this, but it sounds like the resistor unit is bad in the sending unit. Good Luck
Yeah I suppose it is a matter of pulling it out and measuring the resistance as the float is moved, thanks for the reply mate.
It appear that a dirty connection was giving a false resistance reading. When the float is all the way up the resistance is supposed to be zero and then go up to about 160K but with the dirty connection it was reading a lower resistance and thus the needle was going backwards.