ultra 300x bogging down and starting to stall when hitting 4000 rpm range

[Marinedreams]

Hi all
I have a 2013 300x, I sent it to have bottom hull redone, but these clever guys turned the ski over with the oil still in the motor.

What I decided to do was just leave it to stand for about a week, then I removed the intercooler and pipes and cleaned them out
cleaned the airbox

I found water and oil mixed in the lot..
I replaced spark plugs, toped up the oil and decided it was time for a ride..

Ski starts up perfectly, idles perfectly and revs in quick burst perfectly

Now if its on a hose or on the water, if I open the throttle (quick or slow) as soon as hold it in and the ski hits around 4000rpm
it feels like the motor is jerking and wanting to stall on me..

any ideas on what it may be?

I have plugged in a candoo pro and checked for faults.. non found except old embedded fault in the ecu " speed sensor"

PLEASE ANY ADVISE WILL BE OF GREAT HELP AND HIGHLY APPRECIATED

Thanks

Malcolm

[sirbreaksalot]

frozen belt tensioner

[nicjak]

oil in the intake

[Marinedreams]

Ok so today I pulled off the intake, intercooler, catch can and pipes again.. cleaned the lot, there was some milky oil in the intake manifold.
put all back together, but still the same problems...
Cant find any faults..

I'm now wondering if its perhaps related to fuel pump? Gonna change it anyway and then test again..

SO what I noticed today is that out side the water a quick rev will go upto 6800 app in the water a quick rev on the trailer upto 5000
While on the ski test riding and watching the gauges,, the boost of Sc goes up to around 10/11 and will hold there until it begins to chock on itself,,

[Marinedreams]

Ok and its sorted.. turns out the fuel pump was the problem!!

thanks for the help guys!

[K447]

Ok and its sorted.. turns out the fuel pump was the problem!!

...

Was it corroded?

[nicjak]

fuel pump or just blocked filter above it as we have posted how to check.