150 hp oil warning

I have a 150 johnson that runs

I have a 150 johnson that runs fine until full throdle when the oil warning bell goes off . I throdle down a little and it stops beeping any ideas on what is wrong?

"Exactly which warning are you

"Exactly which warning are you receiving?

(VRO Horn Warnings)
(J. Reeves)

1 - A steady constant beep = Overheating - The V/6 engines, possibly some others, have a fuel restriction warning which is also a steady constant beep.
2 - A beep every 20 or 40 seconds = oil level has dropped to 1/4 tank. (Late model engine = Every 40 seconds)
3 - A beep every other second = VRO failure, air leak in oil line, oil restriction, (anything that would result in a lack of oil being supplied to the engine).

NOTE - If the warning horn is the black plastic (overpriced) three wire type horn, the warning horn should beep once when the ignition key is turned to the ON position. If it does not, it is either faulty or someone has disconnected it (a stupid move!). At any rate, if it does not beep which indicates that the horn is non functional, find out why and do not run the engine until the problem is corrected.

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