gas gauge not registering correctly.

[burrpenick]

I finally got my car to the gas station and pumped in 10 gallons, up to now, I have only dumped 5 gallons in it twice at my home. The gauge did not move when I put in 5 gallons, but did go to one quarter of a tank with 10. This is the original tank, cleaned and lined with a new sender and new fuel lines. I cleaned and re installed the ground strap.....what is causing the bad reading?

Thanks, George

[wally426ci]

join the club!! i havent figured mine out either, i have had 2 new senders!!

 

[MEK-Dangerfield]

Here's a simple test.

Take that blue wire that connects to your sending unit, and clip it to ground. When you turn your key to the "on" position, the gauge should register full. This will help narrow the suspects.


   Mike

[burrpenick]

That was my next move- to ground the sender wire, but, I was just happy to finally get the car to the body shop. Its been a long 500 hours of my labor getting it ready!

Back to the gauge.........if that ground pegs the needle, I assume the gauge is working, so what would the next logical step be?  If not, then the gauge needs work.

Thanks,

[LAA66]

 Mine was reading about a 1/8 off. So I bent the float arm on the sender till it read correct to the amount of fuel in the tank. On level ground the tank needs to be less then 1/2 full to get the sender out without spilling gas out the hole.

 Also, when tightening the lock ring the sender can rotate bending the alignment ears which can give a false reading.

 Jon

[burrpenick]

More good ideas, by the way, what is the capacity for the 72 Cuda?

[MEK-Dangerfield]

More good ideas, by the way, what is the capacity for the 72 Cuda?

They were all 18 gallon, so you need to burn off some before you take out that sending unit again.   

[burrpenick]

Yes, if the grounding test pegs the needle,  I will burn it down some for sure and pull the sender. Can someone verify that I need to bend the float DOWN in order for the gauge to read/show more fuel in the tank? I'm guessing it has maybe 12 gallons now and just read 1/4 of a tank. Any ideas of how much I should bend it?

PS: This is a new sender (stainless), but it was one that was made overseas, Taiwan I believe.

[Bullitt-]

If your sending unit is not grounded to the frame you may get below normal or no signal from it..the factory used a metal strap that clips onto the tube of the sending unit & to the metal fuel line...even if its there you may have corrosion that would prevent good connections. Many have added a wire that screw to the nearby frame for best connection.

[LAA66]

 I agree, try a direct ground first as bullitt99 said.

  Bending the float down should make it read higher on the gauge. Check that the float doesn't bind on the pickup tube once bent.  No need to secure the sender while adjusting just snug the lock ring a bit and repeat the proceedure until it reads correct then final tightening. It can also be tested out of the tank using jumper wires. No sparks though.

 The stainless one is what's in my car also. The company I bought it from last summer said they prefer the Tiawan senders as they have had less problem with them.

[MEK-Dangerfield]

I do wonder about these after-market sending units. The originals should of had a range of close to 12-70 ohms. No telling what the after-market stuff is. For the record, my after-market unit reads a tad low. I never quite get a full reading.

George, your's sounds too far out of wack to be useful. 


  Mike

[burrpenick]

I once rigged up a ground wire when the factory strap was boken using small screw type clamps to wedge the ground wire to the sender and then to the fuel line. Is that method OK? I have a new fuel line installed, but maybe it would be better to be attached to something else?

George

[Bullitt-]

The clamps could work but you never know how well unless you check with an ohm meter.
Ohm from the frame to the sending unit, with the wire & clamps the way they are, & see if you have close to no resistance, less than 1ohm.

[Super Blue 72]

   As far as how far to bend the arm to the float, I wonder if you can remove the sender and attach a wire from the sender to ground then move the arm of the sender up and down while it's out of the tank while watching the fuel gauge to get an idea of how it's registering?