fuel gauge question

[Mark G]

I have an inoperative fuel gauge, the sender is new as is the fuel tank wiring to gauge/sender is good. I read somewhere the gauge is a points type gauge my question does the sender which works with an ohm meter need to match the 40 technology gauge 

[greg g]

Single wire or double wire sender?

[Jerry Roberts]

The 1946 Dodge trucks came with a two wire sender .  The dash gauge would have three terminals . You need to stick with using all of the terminals . I once came across a three terminal dash gauge that worked with the stock sender , it would have moved the needle up from the bottom instead of down from the top and the mounting holes would have been different . The dash gauge was from a Plymouth car , station wagon only has the three terminals . Do you have a shop manual ? The dash gauges are adjustable . Also the dash gauges have points the can need cleaning , they are very fragile . 

Edited May 3, 2023 by Jerry Roberts

[B1B Keven]

I have a 3 wire gauge if you want to try it.

 

 

[greg g]

Most of the two wire sending units are offshore items that don't work, or crap out shortly after installation.  NOS are chickens teeth and ridiculously priced.

[Mark G]

I have a three wire, 1 power, 2 going to the sending unit. the sending unit was already in the new tank when we got the truck, took it out tested it with an ohm meter seems to work fine. I just wanted to make sure that did not need to be "matched" I've also read that the price of chickens teeth has come down since Biden took office its the unobtamiom parts that have skyrocketed LOL side not I yesterday I shipped to D&R restorations for them to check it over & hopefully fix it since I've read they are so delicate my fat fingers would surly f--- it up

[Mark G]

thanks Kevin if they can"t fix it I'll be in touch

[dgrinnan]

The 3 wire gauges are very sensitive.  I just wiring mine up over the weekend.  Same set up you described.  New gas tank, new sending unit and original gauge.  The first gauge worked, then it didn't', then it did, then it didn't.  I was not sure if this was a ground issue or what.  I did have the houses hanging free and not mounted in the dash,  I had a spare and switched it out to try the spare.  It was behaving the same way.  I also notice you have to have the gauge upright.  Upside down the needle drops to full. I took a chance it was connections and grounds with the gauge being so sensitive. I went ahead and made sure I had good connections and them installed it in the dash.  It works.  When you turn the key on there is a second or two delay before the gauge moves up.  I am showing about half a tank, which seems correct.  Next test is to drive it to the gas stations and fill up to see if the gauge moves up and to also see if it continues to work while bouncing around driving the truck.  Good luck.  oldmoparts.com has a NOS one but at a premium.  $145.  I would search eBay.  It took some patience and searching but I bought the entire gauge cluster, both units; fuel, amp, oil pressure and temp for $52.  I needed the housing.  The bonus was I ended up with a spare fuel and amp gauge.  The temp had the bulb cut off.  Oil gauge is good. 

Edited May 8, 2023 by dgrinnan

[B1B Keven]

I know a guy that can fix the temp gauge.

Message me if interested.