Fuel gauge

[Bill Cleveland]

Lately my fuel gauge seems to be sticking, and giving false readings. Filled the 10 gallon tank today, and it still showed 1/4 tank. When I got home, I stuck a piece of wire down into the tank and manually lifted the float, so it now shows full, but what gives? My sending unit is similar to this one . . .
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sending unit.jpg (34.75 KiB) Viewed 889 times

[Swampdog]

Mine did that too. Mine had a plastic float. Pulled it out and it had a leak and was filled with gas. Drained it out and sealed with J B Weld and ordered a brass float. That was a year and a half ago and the brass one is still on my work bench. Make yourself a dip stick out of corrugated card board and keep track of the gas for a while that way. MAC Model T parts sell a wooden dip stick but it is hard to see the gas line on. Card board works much better.

[Bill Cleveland]

Thanks, Swampy. I think I have solved the problem: I believe the issue is corrosion on the rheostat from the moisture that collects in the fuel tank. I seldom fill it all the way up, and I'm sure that contributes to the problem. After moving the float up and down several times with a wire tool I made, it does seem to move more freely.

[Swampdog]

The first thing to do before you take the sending unit out of the tank is to put an index mark on the sending unit(plus Gasket) and tank. There is one hole that is a bout .050" difference.