Marine: Boating, Sailing, PWC, GPS and Navigation - Johnson 150hp outboard

I have recently had a rash of problems with my motor and electrical system. Gauges seem to be my biggest dilemma. My fuel gauge seems to have quit working. I found the connections to the sending unit were corroded and I replaced them. The fuel tank is about half full ,however, when I turn the ignition key on, the gauge still does not move from empty. The book that came with my boat(2001 Seaswirl Striper) says the fuel gauge is fused off the ignition. My question is "How do you test to determe either a bad fuel gauge or a bad sending unit?" The sending unit has a black wire which I assume is the ground wire, and a pink wire. Thanks to all who are patient enough to read this and attempt to help.

Built in tank or remote/removeable tank?

The black wire should be your hot wire from the ignition - the pink should be back to the gauges. The built in tank should be grounded to itself - and the system somewhere else.

I'm not an electrician - so can't help with specific amp meters/etc.... However - were I you - I would check for voltage between the black wire and ground - should be 12 volts... If it's hot - you've got power to the tank... which should help isolate the issue... if not - you might have a blown breaker/fuse between ignition and the tank.

Typically, fuel gauge systems are easily removed/replaced - and, if you have power to the tank, I would remove the float assembly and make sure it's actually moving and not stuck in the "empty" position.... At that time I would be able to ascertain whether or not moving the float affected the gauge.... If not - you probably (probably) have a bad float/sending unit - which is inexpensive and easily replaced.

Hopefully some one with more electrical knowledge will chime in - if not - start tinkering....
Good luck.. Z

Thanks Zster.