buzzer sound

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.

Re: buzzer sound

The oil alarm is triggered not just by the fill level of the tanks but when there is a DIFFERENCE in the signals between the oil pump and ignition.

Pulses of the rotation sensor on the oil pump are compared to impulses on the green wire that usually is connected to coil #4, if/when the alarm module see any difference in these two the alarm sounds.

It is possible for a trigger, switchbox, oil pump drive to cause this alarm, you will have to check each one.

Start with adding oil to your fuel to ensure against any oil related failure of the motor.

Then begin testing ignition components, DVA tests, inductive RPM each cyl looking for any difference indicating mis-firing of a switchbox.

Repost your findings.

Re: buzzer sound

Important. Do you get 4 or 5 beeps when you turn on the ignition switch?

Re: buzzer sound

i just bought a 4.3 mercury and there is a beeping noise usually around 20-35 mph, did you find out the problem?