1996 550 Cougar carb adjustment and syncronization - Snowmobile Forum: Your #1 Snowmobile Forum

Muchco · 11-11-2007, 09:17 AM

Hi, I have just finished installing a new motor and adjusting the oil pump. I am going to go through the carbs and want to know if I could get the procedure to coreectley set and sycronize the carbs, or be directed to a web site that has this info? Are the idle screws fuel or air bleed screws, and what would be a good starting point to set them at. I look forward to any and all responses,

regards, Muchco

**RJ Gleason** · 11-11-2007, 09:29 AM

The idle screws are just that, they set the slide height for idle rpm's.
The air screws are the smaller ones closest to the intake end of the carb. They are set at 3/4 to 1 full turn out from gently bottomed. This is the idle to 1/4 throttle air/fuel mixture and is very important that it is set rich enough.
To synchronize the carbs, you can use a vacuum balancer or do it by feel.
I always have worked by feel, starting with the idle screws backed out so that the slides are bottoming, turn them all in an equal number of turns. Then with the tips of the fingers against the slides, pull on the throttle lever. All the slides should start to move at exactly the same time. If not, adjust cable lengths until they do.