1999 50HP Yamaha 4 stroke. Speed loss

[Labine]

Hi

Motor starts just fine. Takes off just fine. Nice humming. At full speed, after about one minute or less,alarm blast off and rpm drop to low speed for a while, then, suddenly ,vrooom! takes off nice again for about one minute and then again and again, slows down.

Any idea colleagues?

Thanks
Labine
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[boats.net]

The alarm indicates it's overheating or low oil pressure and it go into rpm reduction and hold engine to about 2000 rpm's. If you have the Yamaha gauge with warning indicators it will show a temp or oil light when alarm is activated.

[Labine]

Speed loss - Yamaha 50hp

Thanks a lot for quick reply. It's gone to the mechanics and we will see. I'll leet you know.

Thanks again

Labine
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