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| | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | So I am having a problem with the gas gauge on my 51 truck (New 12v gauge btw) not reading at all...it would only stay on empty. I troubleshooted based on all the postings that I could find and nada....so i bought a new 12v gauge...and i am still having same exact problem.
I took the new gauge and hooked up the "ign" to the + side of the battery and the "snd" to the middle post on the sending unit and then ran a wire from one of one of the bolts on the sending unit to the - on the battery....I manually moved the float for the sending unit and got no reading at the gauge, no movement, nada.
I then took the sending unit and hooked up an in-line light from the the middle stud of the sending unit to the + of the battery and from one of the outside screws to the - in the battery...moved the float by hand the light dimms from one position to the other...which leads me to believe the sending unit is fine.
I am now thinking of buying a new gauge from a different Vendor in hopes that the issue might be a bad batch...but I am thinking it is too much of a coinsidence to have two gauges bought in different months to go wrong.
The only funny thing I noticed is when I hook up the gauge to the sending unit and I removed the negative going from the sending unit to the - in the battery then the neddle moves to about half full...if I ground the sending unit then it goes right back to empty...this without the sending unit being inside the tank and even manully moving the float to the full position...
what am I doing wrong? any help | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | A majority of the new fuel gauge problems are due to a bad ground.
Is the gauge grounded when you test it?
There a a small plate on the back of the new gauge. It needs to touch metal in the gauge housing.
One other thing to look at is the needle. The new gauges has the needle sitting higher and it could be pinched by the bezel.
That's just two things to look at. | | | | | Joined: May 2005 Posts: 1,624 Shop Shark | | Shop Shark Joined: May 2005 Posts: 1,624 | +1 on what DADS50 said. You've got to ground the sender AND gauge. With that said, have you matched the resistance of the sender with the resistance of what the gauge wants to see? If you have a VOM (volt-ohm-meter) and a variable resistor, as past posts state, one can troubleshoot all.
Six volt guy living in a twelve volt world
| | | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | DADS50 and Belfed thank you for the info. Both of the call outs on DADS50 were right on. The ground tab on the gauge was not making proper contact with the housing and once I got it to work the neddle was pinching the bezel....I know have a working fuel gauge :-) Thx | | |
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