Gas Guage.

[Boomyal]

Just reinstalled my sending unit and noticed it was all rusty. Just filled the gas tank and noticed the guage did not register. Can I short the positive lead to determine if the guage works? If so, where do I look for a new sending unit. It is 30 years old.

 

[Dunaruna]

Re: Gas Guage.

Yes. turn ignition on, disconnect the sender wire , touch it to a good ground (the ground wire screw). The gauge should peg out to full. If it does, your sender is faulty. If it doesn't, the sender wire, ground wire or gauge is faulty.<br /><br />VDO make a whole range of senders to suit different size holes and different depth tanks, some senders are even depth adjustable. The sender will have an 'OHM' range - this HAS to match the gauge. Some OHM ranges are backwards, look on the back of your gauge, it should be printed there.<br /><br />For instance, you may find '10 - 180 OHM'.<br />Or you may find '240 - 33 OHM'.<br /><br />The gauge and sender need to match exactly.

 

[Boomyal]

Re: Gas Guage.

Originally posted by Dunaruna:<br /> , look on the back of your gauge, it should be printed there.

Even on 30 y/o guages??

 

[Dunaruna]

Re: Gas Guage.

O/K, good point.<br /><br />On the really old senders, the markings were stamped in the top rather than printed (sort of like an engine number). Remove the sender and introduce it to the buffing wheel, you may find the numbers there.<br /><br />Failing that, you will need to buy a matched set.<br /><br />EDIT: Just thought of another place to look, the sender itself is a coil resistor mounted on a plate, sometimes the numbers can be found on that plate. You will see what I mean when you remove the sender, a metal strip rubs up & down on the coil.

 

[Ralph 123]

Re: Gas Guage.

Boom, Check these out and bookmark for future ref:<br /><br /> http://www.tflx.com/tech.html <br /><br /> http://www.tflx.com/pdf/marfue~1.pdf <br /><br /> http://www.tflx.com/pdf/GAUWORK.pdf <br /><br /> http://www.tflx.com/PDF/99179.pdf

 

[Wimperdink]

Re: Gas Guage.

not sure if this will help but I had the same problem on an older mazda truck. I pulled the unit out of the tank and found there was alil piece of tin that stays pressed against a reostat. The tin with age and the sloshing of the float arm caused it to bend out a lil making the tin not touch in all positions... I bent the tin back against the reostat and moved the float arm up and down making sure it was making contact in all places and put it back together... has worked great ever since... saved about a 150 dollar part.<br /><br />Once again i'm not sure this applies in a boat gas tank but just my two cents.

 

[bosavy]

Re: Gas Guage.

If it;s only rust sand down the terminal and reinstall it should work great.there's a little half ball that runs down the resister.Only sand that ball not the flat piece .Ohm test after your done