have a 1989 mercury 150 xr 2. The main oil tank is full and the small tank on side of engine is full. When boat is runing from 20 mps to full throttle there is a small beeping sound coming from console. Tookthe cap off the oil tank on engine and noticed that the small cork gasket on the oil tank was cracked. Took cap off and replaced with new cap and hooked wires back up to engine. Then crank engine up with cap loose to fill tank up . Once oil starting coming out at top of cap cut engine off and tighten cap up. Made sure oil filled the tank up. Still having a beeping noise coming from the buzzer system. Motor smoking good, not knocking, not over heating. What could be the problem. Motor is only used about 20 times a year. Stays in garage when not be used.