I have this 87 70 HP mercury engine that has a continuous beep. It goes away once I throttle up. Ran all day so I wanted to see if it used any oil. The tank was still full at the end of the day. Would the engine use very little oil? I took the tank out and wondered if it is the tanks switch or the pump. I hate to order a pump since it is exspensive since it may not be that. I'm leaning to the switch. The boat ran well except for the constant beeping. Would you agree or have a better idea. New to boats and the problems that go with it.