Broken Fuel Gage


I recently brought a 1996 fourtrak, it hadn't been used for a few months prior to purchase but passed its MOT. The gauge doesn't seem to work on the fuel, when the tank is full its creeps up to the 1/4 full mark any ideas what could be wrong? Tank is definitely full interestingly when we had heavy rain damp weather it moved up could it be something to do with the connection to the tank?.Thanks

Sender Unit.

Could be the connections between the gauge and the tank sender unit. However it is more likely to be a fault with the sender unit which is inside the fuel tank. The tank will need to be dropped to remove the sender unit ..... is it worth the bother and possible additional damage in the removal process?