Who sells NOS fuel gauges for...

[ChargerandVette]

...a 69 Charger R/T?  I installed a reproduction fuel gauge from Year One but it constantly reads full even when there is only a quarter of a tank of gas.  The gauge can not be adjusted.  The sending unit in the tank is the original one.  So because of the problems with the repro fuel gauge, I'd like to go back to the original.  Thanks

[Charger-Bodie]

Sounds like somethings grounded out.

[tan top]

   yeah 

[ChargerandVette]

Okay, I just finished checking the fuel gauge again.  This is what I did...I disconnected the sending unit wire at the sending unit.  I connected a jumper wire to the threaded stud on the sending unit.  I then connected the other end of that jumper wire DIRECTLY to the sending unit terminal on the brand new Year One fuel gauge.

I then connected a jumper wire DIRECTLY from the 5 volt output, I tested the voltage and it is 5 volts, to the 5 volt terminal on the new fuel gauge.  I turned the key and the needle went up to a little less than 3/4 of a tank.  By the way, I'm not sure how much gas is truly in the gas tank. 

Here's the problem, I tested the original gauge the same way to bypass ALL possibly ground shorts.  The original gauge read exactly between 1/4 and a 1/2 (3/8 ths of a tank).   So since both gauges gave different readings, I don't know which gauge to believe! 

Here's some background information on the original.  I had to repair it after the voltage regulator went bad.  A tiny wire near the thermal metal strip broke so I reconnected the two ends.  The wire does have continuity now.  And at the bottom of the needle, where it hooks into the lower gold colored strap of metal and the hook on the thermal strip, I took some play out of it.  The play made the needle jump up or down as it was in motion as it neared a 1/4 of a tank. 

The resistance value of the brand new fuel gauge is 15.7 ohms.  The original is 08.7 ohms.  The test was performed with each gauge completely removed and only the two terminals being touched by the multi-meter probes.  I'm thinking the different "built-in" resistance values could be throwing the readings off.  Also, I get the same exact fuel gauge readings when I use the original sending unit wire instead of the jumper wire.

Here's my question, is 15.7 ohms too high?  Remember, I'm talking about the fuel gauge being completely out, not hooked up to anything, when it's resistance is tested.

Any other ideas? Thanks

[ChargerandVette]

Before I got out of bed this morning, I had an idea.  I have a working sending unit from my 55 Chevy Bel Air.  I will use that sending unit to test the original gauge and the brand new gauge.  I know the Charger sending unit is different from the 55 Chevy's but this way I can see if the needles move to the same point on the gauge face.  Both the new and old gauge will be out of the car and the sending unit will be in my hand so I can move the float arm with my fingers.  I won't forget to ground the sending unit to the car's chassis and use only the 5 volt output for the gauges.

This test should tell me if the new gas gauge and old gas gauge needles give me the same reading since they'll be receiving resistance information from the same sending unit that will be easily controlled by me in my hand.  Each gauge will be tested independently from the other.