On my Skeeter SS90 my gas needle is staying at the full indication. When I pull a wire off of the sending unit in the top of the tank the needle will fall probably due to lack of current. I only have one tank so it cant be a switch. Any suggestions on things i may check out myself before having to take it to the shop. I am just finishing up restoring the boat so I dont know for sure if the gauge woked before. Any help would be greatly appreciated.