18 Classic gas gauge inop

[fwi]

Not being very good at diagnosing electrical problems, I thought I would ask the experts about this problem.
Gas gauge worked the other day when I filled up the tank and turned the iginition on to check level.
However, when I splashed the boat to go out, fired up the engine, the gauge shows empty and low fuel light is on!
Any ideas on where I should start?:confused:

[mrfixxall]

ck at the tank sender for a good ground or unser the bow,the ground may be connected to a tab welded to the fuel tank..if you have a test light find a good groung and probe the center ternimal if the sending unit goes up then you may have a bad sender and or connection..