fuel

I have a 48 gallon fuel tank that the fuel guage registers full all the time. I pulled out the sending unit and moved the float up and down and the guage and the unit registers fine. I put the unit back in and slowly moved it up and down and everything registered. I checked for obstructions in the tank and screwed the unit back in (poly to poly). It still registers full no matter what the level. I tried to recreate the possible flexing problem but could not find a problem. The tank is mounted in a 21' center console cajun fishmaster. Any suggestions? Thanks.......Wes

Re: fuel

Wes,<br /><br />If you keep posting to the same thread it's much easier for everyone to follow your progress and help you.<br /><br />For the gauge to read full means that someplace the two wires to the sender are shorting together. Since the sender works out of the tank and not when installed, something is changing.<br /><br />I still suspect the sender. Remove the wires from the sender and measure the resistance across it. If it's close to zero ohms without the tank being full, you have a sender problem.<br /><br />You can then verify this by removing the sender and measuring the resistance as you move it through it's travel. You'll see the resistance changing and you'll know what it's suppose to be.

Re: fuel

wes. this don't really answer your question. but i got to say it. probably get lots of laughs from all here at iboats. don't know how yer tank is mounted or if ya can, but personally i use a fuel stick to see how much fuel i have. depends on if yer fuel tank is right under yer filler hose i guess. works very well if it is, and is very accurate. best i can tell, even a funtioning fuel gauge is pretty inaccurate from what i read about boats. mine, in my boat works, and i'd say it's inaccurate at best. bounce's up and down and the likes. as for yer unit. perhaps when it's (the sender) is wet with fuel it don't work. shorted maybe. don't seem like it would be the fuel gauge since ya can make it move when the sender is out. perhaps its a short in a wire somewhere between the sender and the gauge. or corrosion on any terminal from the sender up to the gauge. perhaps ya could find the spec on your sending unit. in ohms. go up to the dash and ohm out the wire comeing from the sender up at the dash. see if its sending the right info up to the gauge. personaly the fuel stick (1/4" wood dowl, 3' long or so)works best for me. + ya can get some laughs at the marina dock when ya get yer fuel stick out. hope someone else has a better idea for ya......

Re: fuel

and screwed the unit back in (poly to poly).

Click to expand...

Where, Exactly, are you connecting your Ground ??????<br /><br />The sending unit has to be Grounded to the Battery.......<br />And,<br />The Tank has to be Bonded to the Fuel Fill Fitting,+ the Engine Block................

Re: fuel

Yep its grounded to the battery and was all factory installed so I guess they knew what they were doing. As I said I can slowly lift the unit out of the tank and the guage registers fine. The are no bare wires or grounding out and the unit works fine when wet. I gently wedged the float down to the empty position reinstalled the unit. The guage showed empty. so I don't know but thanks for your input.