carb or cavition problem..both or neither??

[gcha1727]

I have 2 acceleration problems with the 787..not sure if there related.

1st, when trying to go past 5500rpms it surges to around 6k rpms and then back and forth. Full throttle the boats rpms goes up and down between 5 and 6 k rpms. It never goes higher than 6k.

2nd, sometimes on that same motor it will stall and/or sputter at low idle. Sometimes difficult to accelerate.

Runs good on trailer.

Compression tested good. Raves move freely.

Thanks

 

[Dr Honda]

1) Running on the trailer won't tell you anything, since there isn't a load on the engine.

2) If you have cavitation... the RPM's will go to full, and you dont' accelerate.

3) What was the compression?


So... that leaves us with a fuel issue. Clean the carbs, fuel select valve, and filter.