Have got the wires done to the point of turning over the motor (first time running in the boat since 1989 ) It fired right up but the oil gauge pinned to the max just turning the key on and stayed like that after starting . Tracing down the problem I find Volvo Penta has an oil sensor and an oil sender , the oil sender ( the one just behing alternator ) is missing and a brass nipple is in the block . There are wires coming out of the harness just cut off , 2 black and one blue or green . Do these go to the sender and do I get a new sender and try to wire myself or do I need to test resistance , voltage or ohms ?. I fell Im going over my head here and dont want to fry anything in the harness . I need to be pointed in the right direction I hope thats not the dealership .