Engine cough 1991 200 Yam 2 stroke carb

[CaptRandy]

1991 200 hp Yamaha 2 stroke carbed engine
Engines ran well through last fall, now that put back in water the stbd engine is slow to gain rpms as accelerate. Port goes right up to 3200 but stbd lags behind for a minute until it catches up. Additionally this past weekend stbd has gotten a cough. It will "idle" fine with throttle pushed forward at about 1100 rpm but when try to bring throttle back to idle of about 600 it begins to cough and then stalls out. Carbs were rebuilt spring 2013 fuel tank was also pulled and entirely cleaned at same time. New plugs were installed fall last yr.
Where do I start? fuel pumps(2 of them) adjustment screws?

[99yam40]

lean sneeze
should not have to readjust anything unless someone messed with them or you did not set them properly after cleaning.
If it ran well after reinstalling then you probably need to pull and clean again, pilot circuits a plugging

Fuel pumpe need replacing from time to time ,but I do not think it would cause a lean sneeze at idle

[jeffbare]

I just want to keep this thread going, I am having the same problem with my 1991 ProV200. Me neighbor the same problem with his V6 Merc, and it was the thermostats.

[boscoe99]

Two motors can have the same symptoms but have a completely different problem.

The cooling system on a Mercury can be completely different than it is on a Yamaha by the way. Thermostats can fail open or they can fail closed. The problem seen would be completely different but I am failing to see the connection between a thermostat issue and a coughing issue.

And if the symptoms that you are experiencing are the same as the OP of this thread then the same general answer might apply. Coughing is also known as a lean sneeze. First guess is that the carburetors might need to be cleaned. Or, were yours cleaned about a year ago as were the carbs of the OP of this thread?

Why not start your own new thread? You will generally get better answers this way.