1972 gas gauge issue

Hey, I have dropped the tank few weeks ago. I cleaned out old gas and replaced the sender with stainless steel, the gauge worked. Went to drive but the gauge only moves up to the empty line(it moves with the key turned). Figuring I had no gas I added 5 gallons and still only reads empty. I have a power probe, all grounds good, get a ground signal from one connector and a pulsing ground/ positive from the other. If I ground the pulsing wire the gauge moves all the way. What else can it be? bad sender? Let me know what you think

Alex

It may be as simple as the arm for the float is positioned improperly and binding rather than allowing it to move freely. Top off the tank, and drive far enough to get the tank down to appx 1/4 and remove the sender and move the arm with it all hooked up and grounded to see if your sender is working properly. Also your float, if it leaks will fill up and cause a similar problem.

Even thou its brand new, new really drove but once

I took a brand new crap this morning. It was brand new! But it was still crap. With repro parts, testing before installation is important. Bad parts are not at all uncommon.

If you have a ohm meter take a reading between the 2 studs of the fuel float assembly. If the tank is full you should see about 10 ohms and empty about 74 ohms. Half tank would be about 42 ohms. If anything around 70 ohms then the gas gauge should be above empty but just barely..

I took a brand new crap this morning. It was brand new! But it was still crap.

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Yeah, but I bet you still enjoyed it. :whistling:::shrug::

I had the float come off of a brand new sender once, shortly after installation...I had the same symptoms

Good morning, the ohms are 74 at the pins, I guess the sender has to come out...EERRRR

if it makes you feel better i had to replace my sender 4 times before i got one that worked semi correctly and didn't leak out the seals for the connector.

You should feel lucky, at least they make the sender with the tube facing the right direction now....

OK so i pulled the sender, float was intact. I raise and lowered the float and the fuel gauge is reading properly. I guess I will put it back and see, lol

If the sender is turned too far in either direction the arm will bind. There is a sweet spot where it works best.

I put it back and reads only E...placed 5 gallons and doesnt move past E.....ANNOYED

try to reverse the connections if you can, even if you just do it with jumper wires. If that doesn't get it and a meter is stlll showing the sender to be good, then you may need to get behind the dash.

On the back of the instrument panel is a CVR that cuts the volts down to 5 or so for the gauges. Originals have a small screw for fine tuning. Some replacements don't this screw. It is possible that you need a new one, or that yours needs adjustment.

try to reverse the connections if you can, even if you just do it with jumper wires. If that doesn't get it and a meter is stlll showing the sender to be good, then you may need to get behind the dash.

On the back of the instrument panel is a CVR that cuts the volts down to 5 or so for the gauges. Originals have a small screw for fine tuning. Some replacements don't this screw. It is possible that you need a new one, or that yours needs adjustment.

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With the sender out, moved it by hand and the gauge moved accordingly

Weird, I think that would be a bad sender.

Weird, I think that would be a bad sender.

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tell me about it:huh:, I was thinking the float is full of gas, but I think I would have noticed it

Look closely at the brass float

I have seen them crack

If it is just the float, let me know, I had a bad sender and think I kept the float for such an occurrence