2006-2008 Yamaha Snowmobiles Apex/Attak Factory Service Manual, Page 71Get this manual

2006-2008 Yamaha Snowmobiles Apex/Attak Factory Service Manual, Page 71

CARBURETOR TUNING Main jet selection chart Spark plug color Light tan or gray Dry black or fluffy deposits White or light
with low-speed tuning Adjustment Return the starter lever to its seated position so that the starter valve is fully closed
Fuel passage is clogged or Check and, if necessary, clean the fuel frozen tank air vent, the fuel filter and all of the fuel
passagesS Check and, if necessary, clean the carburetor air vents, fuel passages and the float valveS Clean the float chamber
of any ice or waterOverflow Poor idling: Poor performance at low speeds SP Poor acceleration ti Slow response to res onse
throttle Engine tends to stall Improper idling speed adjustment Damaged pilot screw Clogged bypass hole Clogged or loose
pilot jet Adjust the fuel levelAdjust the engine idle speedRefer to "Low speed tuning"Replace the pilot screwClean the bypass
holeS Remove the pilot jet, clean it with compressed air and then install itS Make sure that the pilot jet is fully tightenedRetighten