Gas and trim gauges not working

[anthony10092]

My trim gauge bounces all over the place. When I put it away last year it worked fine, but this year it is just all over the place. Also, when I use the trim up switch it doesnt always work. I have to use the trailer switch to raise the motor up. I am going to look at wiring for that issue but am not sure where to look other then right at the switch. The gas gauge worked as well. I put 30 gallons in a 50gallon tank and it is reading just above empty. The lights work on th egauges when I turn the key on so I know they are getting power. Do these gauges go bad over time or is there something in the wiring? I am not sure where to start. Thanks for the help!!!!

 

[Silvertip]

Re: Gas and trim gauges not working

Gauges themselves are rarely the issue when they don't register correctly. Wiring and senders generally are. Trim sender is at the engine. Fuel sender is in the tank. Fuel sender resistance is 240 ohms empty, 109 ohms at half full and 33 ohms full (give or take a bit on all readings). Here is the diagram for the fuel gauge system. Trim works in the same manner but with a different sender. The sender is specific to your engine so you need the factory service manual for its wiring.