Engine stalls when throttled back

[Catch 22]

Need some advice as to what to try. It gets real tricky when I am headed down a tight runway and need both engines to get in/out of my slip. Yamaha 9.9 stalls whenever I pull the throttle back. It starts alright but idles a bit rough and sometimes will stall when apply throttle unless push it well forward right away. Biggest issue if we have been running the engine at speed for a while it stalls when the throttle is pulled back to idle, starts right back up but won't idle smoothly and stalls as soon as you apply throttle unless pushed well forward rapidly.

Any ideas are welcome.

Catch 22

[Allezcat]

Sounds like carb needs cleaning. Idle jets are likely gummed up. Remove carb, disassemble completely, clean all parts with good carb cleaner, blow out with compressed air, reassemble. When you accelerate quickly, a pump squirts fuel into carb which allows engine to accelerate. If you accelerate slowly, the lean mixture (caused by plugged idle jets) causes the engine to stumble or stall.

Chet

[thinwater]

Exactly.

You may get by, for a time, by simply advancing the idle speed a fraction of a turn, but a fast idle is tough on shifts and prop hubs. The mixture needs fixed.

If by chance you have a carb with ajustible idle mixture (made for Canada engines), you might try adjusting the screw out 1 turn, but COUNT THE TURNS so you can put it back.

But Allezcat is corrrect.

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[Catch 22]

Great! Thanks for the advice it was pretty much what I thought. Now for the real question...can you pull the carb with the motor in the water? Pulling the motor is problematic for me without pulling the boat. If so, I am sure you guys already know the tricks to it.

[Marc Gershel]

Check May, 19 thread on this subject.

viewtopic.php?f=20&t=2505

Marc