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fuel sender question

gwstang

Member
I had to drain my almost new tank to move the electric fuel pump last week (new exhaust installed). Now the gauge (electric autometer) only reads half full when the tank is filled up. Did the float arm on the sender slip or something? I did ground the wire for the gauge and it went to the full mark (so it's working), any ideas? The sender is also new and was working fine for a couple of months until the tank was drained.
Thanks, Gary
 
Did you do anything to the sending unit when working on the tank? How did you drain the tank? If you siphoned it, the hose may have hit the float and messed it up. Double check you tank grounding and the sending unit grounding.
 
I'm using an efi setup with the return line going into the corner drain plug of the tank. So I just used the line coming off there to drain the tank.

The tank has to be grounded? I did remove a couple of the bolts that hold the front flange of the tank so I could use some longer bolts to attach the fuel pump at that point. Seems like it wouldn't work at all if it lost the ground.
 
Odds are the tank is grounded but you could still do a little test by grounding a wire from the chassis to anywhere on the sending unit flange, snout, etc.

I wonder is somehow the arm is sticking halfway up, meaning is the arm itself rubbing against the sock at the end of the sending unit? Another possibility is a hole now in the float. As soon as you remove the sending unit, you might simply remove the float and lightly shake it to hear for gas slushing around. Otherwise remove the float and submerge it in a pot of water to see if there's any holes in it.
 
Argh! I hate the thought of removing that thing. I seem to have a terrible time getting it to seal up again. :rr
 
I can send you my sending unit lock wrench as well as a new O-ring. I'll tell ya how to seal up the O-ring.
 
You are a great fellow for offering. I can do it, it's just the 15 gallons of gas I have to drain out...ugh. Remember the dented fuel tank from the jack episode? I had to get a new tank so I have an extra sender/o ring because I got the kit. I'm just getting whiny in my old age...Seems like somethings on these cars has to be done over...and over...and over... :shee It never ends.
 
Yes, the drain plug is where the efi return line is at. I'm using an efi pump but have not done the wiring yet. I'm working on the wiring harness now to get it ready for installation. You would know after getting the new exhaust system installed, I went by and filled it slap up with fuel! I watched the video so maybe I won't screw it up too bad. Damn, I just pissed Randy off recently too...ARGH, curse is coming my way! :shee
 
"gwstang" said:
Yes, the drain plug is where the efi return line is at. I'm using an efi pump but have not done the wiring yet. I'm working on the wiring harness now to get it ready for installation. You would know after getting the new exhaust system installed, I went by and filled it slap up with fuel! I watched the video so maybe I won't screw it up too bad. Damn, I just pissed Randy off recently too...ARGH, curse is coming my way! :shee

You did poked the bear recently, didn't you?
 
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