fuel gauge, 1937 Pymouth sedan

[dmartin_egroup]

The fuel gauge on my 1937 Plymouth car is not indicating tank level.  When ignition key is off, gauge is pegged below the empty mark.  When I turn the key on, the pointer moves up to the empty mark, but no further.  It did this today after I topped off the fuel tank.  Therefore I say the gauge is not dead, but is not indicating correct level.  Can anyone tell from these symptoms what things I should check, and in what order?  Thanks much!  (Oh, by the way, I did have a nice ride around the countryside today, gauge or not!)

 

Dennis M. in W. Tenn.

[Niel Hoback]

Sounds like your float sank.

[dpollo]

Niel is likely correct I would first check the tank unit.  If you put a clip lead on the wire at the tank, the gauge should indicate Full.

[Trevor]

Tank gauge voltage is very low.. you need to adjust that float level.. check it..

 

[dmartin_egroup]

Hi, Dpollo:

Would I be applying ground or battery voltage using my clip lead??

Thanks for assistance!

 

Dennis M. in W. Tenn.

[harveyspoint]

If your float sank, you can get a new one that is not affected by the alcohol in the new gas.....I got mine from Snyders Antique Auto Sales in New Springfield, Ohio....Page A-144, in the 2017 catalog, top left, for $4.25....I bought two, but I only needed one for my '48 Plymouth Coupe....now, I have an extra for my '47 Coupe....This is a cork float and they used shellac to seal the float...Alcohol is the thinner for shellac and after 70 years, the shellac disappears and the float gets heavy and just barely floats or, in my case, it sinks...Snyders is a Ford Model T & A

shop, but no one will know you have a Ford part in your Plymouth...They say this is the last float you will ever have to replace...

[dpollo]

Just a ground at the tank.   If you use a test light, it will glow and the gauge might read 1/4.

 

Chrysler offered a fuel sender designed for auxiliiary tanks which, after shortening the float arm will work your gauge perfectly.

The part number is no longer listed but I can look it up for you if you send me a PM.    There must be a whole bunch of them out there still since they were still available well into the 90s.

[dpollo]

Try to find tank unit Mopar 2240729 as described above.  It works on single wire circuits as used in 37.