how to calibrate a fuel gauge

[roc111672]

My fuel gauge doesnt work properly how can i calibrate it so it does ? When it shows it is empty it is half full . Thanks for any help , Roc

[turbolicious]

Not sure of your boat but on my 1987 comp There is a black box under the dash, there is 4 plastic pop pins, I belive the third one is the fuel light level, By turning one way or the other you can adjust sensibility

[turbolicious]

Oupss just saw the top post, I belive my information dosen;t apply to your boat!

[csuggs]

On an 87, I'm thinking that you will need to partially remove the sending unit from the top of the tank (there should be an access plate from your rear ski locker). Pull the sending unit out far enough so that you can bend the float arm and adjust the height. I think I would dip a ruler in the tank to measure how much fuel you have, then bend the float arm so that your gauge matches the amount of fuel as determined by the ruler. That's how I'd do it - but there's probably a more "scientifical approach" somebody else may be able to describe!