Problem with Mercruiser above 4000 RPM

[Wyomingman]

Took my boat out for the 1st time this year today. The boat is a 2002 4.3 MPI Mercrusier Alpha One. The boat idles nice, excelerates good and runs great up to 4000 RPM's. Once is reaches 4000 RPM's it misses or purges making the boat decelerate fast. Once below 4000 RPM's it then runs smooth. Any idea what this could be?? Thanks for the help.

 

[dubs283]

Re: Problem with Mercruiser above 4000 RPM

check tune-up condition

check fuel condition

are you sure tach is correct and you aren't hitting the rev limiter??

 

[Wyomingman]

Re: Problem with Mercruiser above 4000 RPM

I removed the fuel water separator and it seemed to have quite a bit of water in it. Bought a new filter at NAPA today and will replace. I will also put Seafoam in that hopefully will help. I fuel tank was only about 1/4 full over winter but it did have Stabil in it but i think condensation could still build up???

Another question, is there another fuel filter on this engine I should check besides the fuel water separator? The engine serial number is OM322808