Engine stutters on hard acceleration

[Cam.Davies1980]

Anyone have any ideas as to where to start when trying to remedy a "Stutter" when hard acceleration on a 1999 90 HP 2 stroke Mariner Outboard?? Seems to be better when slowly accelerating into full throttle. And when I get there... I feel that I am missing some valuable RPM's. I haven't thrown any parts at it yet, but my instinct is to go with fuel filter to start off. Thanks in advance guys/gals!

 

[Glastron_V210]

Sounds like fuel. Does your carb have an accelerator pump? If so perhaps it's not functioning up to spec?

If not, look at the usual things, fuel filter, fuel pump, carb clean/float level etc.

Chay

 

[Texasmark]

Hard acceleration means you are asking for max fuel and not getting it. When is the last time you re-did the fuel supply lines in/to your engine including cleaning the carbs (kit) and a new fuel filter? If never, start with that. You're overdue for some fresh rubber. Mine started giving me problems at 10 years on a 2002 90 triple just like yours! No accelerator pump on that engine as far as I know.

If all that checks out then compression check wouldn't hurt.....manual says 120 or over cranking with all plugs out. Less it says to "expect problems".

Then, what kind of rpms are you running at WOT. That engine is rated to 5500. If not up there you could have too much prop. Is this a new problem or has it always existed? What kind of hole shot do you have?