88 5.0 omc falls off after half throttle

[Vortecus]

88 5.0 omc 4V

Engine idles fine when throttle up to full engine stumbles and rpms drop back.Feels like a fuel filter but have new one in and also water separator is new. Threw a few parts at it including Carb,points,Plugs Tested coil has good spark does this have a rev limiter.Trying it with muffs and same problem .This is in neutral

 

[RogersJetboat454]

Re: 88 5.0 omc falls off after half throttle

Welcome to Iboats.

Take a look at this as a guide for what to check.
http://forums.iboats.com/showthread.php?t=295070

P.S. Free reving an engine in neutral is not a good idea.

 

[Vortecus]

Re: 88 5.0 omc falls off after half throttle

88 5.0 omc 4V

Engine idles fine when throttle up to full engine stumbles and rpms drop back.Feels like a fuel filter but have new one in and also water separator is new. Threw a few parts at it including Carb,points,Plugs Tested coil has good spark does this have a rev limiter.Trying it with muffs and same problem .This is in neutral

I checked everything on list all ok except 1 flapper missing .Used an inspection camera to make sure it was not lodged in pipe or bellows.No obstructions any other suggestions ?