Engine was fine then couldn't rev up then fine again (video attached)

[jackwoz2]

Hi Guys,

I took my boat out for the first time in 2 years. All was well then suddenly it sort of idled and wouldn't rev very much then suddenly it kicked it and all was good. It seemed to happen at the same point in the lake several times. Probably going into the wind.

I happened to get a video of it when it idled then suddenly revved up.

Could anyone point me to what i need to investigate. I have little knowledge but im assuming it a Fuel/air/Spark problem? Or even carby?

Video link here: https://youtube.com/shorts/Bw2YNnvUBxA?feature=share

Parsun (Yamaha E40 Clone) 2 stroke 40HP

Thanks for any help

[99yam40]

my guess would be overheat, low oil level on a 2 stroke.
but I have no idea what motor you are talking about

[jackwoz2]

Sorry mate neglected to mention the engine type. Parsun (Yamaha E40 Clone) 2 stroke 40HP

[99yam40]

China knockoff outboard, never even heard of one before much less seen one
no idea
who knows what it might be

[panasonic]

Try pumping primer bulb while it is struggling to rev up. If that helps then check fuel filter, change filter if dirty. If it don't help, check fuel pump and clean carby.