Inaccurate fuel gauge reading

[DABJEEP]

My 1951 M38 was "Billy Bob" rigged for many years before I started a frame off rescue/restoration 3-1/2 years ago. The project is now complete and it turned out to be quite nice. During its' rigging years, all of the gauges were removed along with the original engine. It has a L134 engine in it that came, according to the block s/n, a Jeep truck. The electrical system at some point was changed to 12 volt. Since the system is now 12 volt, I put in a CJ3A sending unit in the fuel tank. Was told that it would work fine and when it showed "empty" there would still be a couple of gallons in the tank. However, when the tank is full, the gauge registers between 1/4 and 1/2. Do I have a bad sending unit? Are there any suggestions for getting a accurate reading on the fuel gauge?

Thanks

[wesk]

Put a 12 volt gauge in.

[DABJEEP]

Wes,

The new gauge that I purchased from Kaisar Willys is 12 volt, 3 post. Do you think I have a bad gauge? Do you have any more suggestions?

Thanks,

Don

[wesk]

OK let's review what you have.

1-M38 gas tank. (This tank is much deeper than the CJ3A tank)

2-Civvy 12 volt gas gauge.

3-Civvy 12 volt sender for the shorter 3A tank.

So if #2 & 3 are a matched set and the system voltage is 12 volt and the tank is well grounded to the tub and the gauge is grounded to the dash then all should be well with the gauge & sender. This leaves the travel of the senders float. Since the float sender is for the shallow 3A tank then it's safe to assume it's travel range from full up (tank full) and full down (Tank empty) is not long enough for the extra height of the M38 tank. Your solution without spending a lot more money is to increase the length of the sender's float rod so it can reach the bottom and top of the M38 tank.

[DABJEEP]

Wes,

Thanks. I'll give it a try.

Don

[4x4M38]

I have a really nice CJ fuel tank in my M38 that is decently clean inside.

We could swap tanks and you'd be golden.

Grins,
Brian