1977 V20 fuel level sensor on tnak not working

[Bryan's 1977 V20]

Hello,

I have a 1977 V20 step and a 1977 175 Johnson outboard. The fuel sensor on the boats fuel tank will not move past 1/2 even when tank is full. How do I fix this and are there any parts I can just replace it?

[Greyduk]

Bryan I have recently replaced the fuel tank sending unit on a 1987 V20 and a 1994 V21. In each case I replaced them with a Moeller sending unit. You will need to know the depth of the tank to get the correct sensor. One was the 6-12 inch tank depth model and one was the 4-24 inch model. At any rate, there isn't much to it. Only removing and installing 5 small screws. In the case of the V21 the gauge was the culprit as I came to find out. I replaced the gauge any way when I redid the dash. Not too difficult of a job. Good luck.

[phatdaddy]

Do you have one tank below deck or saddle tanks in the gunnells?

[bradford]

Pretty easy fix although boat fuel gauges and sending units can be very inaccurate even when new. I haven't run one in years, but plan on installing a mechanical gauge this summer if I ever get caught back up.

[SkunkBoat]

Google "moeller fuel sending unit instructions".
The float type have to be adjusted correctly.

Also, make sure that the float isn't hitting a baffle in the tank when it swings