RPM reduction and buzzer sounds

[coralway]

I have a 1989 200 HP V6 engine when I run it at full trottle the rpms will
reduce and the warning buzzer goes off if I shut it down and crank it back up the buzzer is gone and engine is fine, I recently had the powerhead done and lower unit I am mixing the oil directly into the gas and I never bypassed any of the low oil sensors on the boat but
never had any problems from that

any help/advice would be appreciated!!

Thanks Rene

[boats.net]

It is probably the low oil warning, if it's overheating the buzzer would stay on until it cooled down. If you are not using the oil injection then disconnect the oil level sensor on engine oil tank. Also disconnect the harness going to oil tank in boat.