Yamaha MM700G, Owner'S Manual

Page: 61 / 96

8-9
CD-04E
1. Loosen the carburetor clamps and remove the carbu-
retor.
2. Pinch the fuel hose to prevent fuel flowing.
3. Remove the drain plug and install the proper main jet.
4. Assemble by reversing the removal steps.
WARNING
@
Make sure that the throttle outer cable is firmly
seated in the holder and throttle operates smoothly
after assembling the carburetor.
@
ESU00157
High altitude adjustments
Operating at high altitude reduces the performance of a
gasoline engine to about 3% for every 305 m (1,000 ft) of
elevation. This is because there is less air as altitude
increases. Less air means less oxygen available for com-
bustion.
Your snowmobile can be adjusted to overcome most of
the problems found in high altitude riding. Carburetor
adjustments are the most important. Less air at high alti-
tude makes the air/fuel ratio too rich, which can cause
poor performance. Common problems are hard starting,
bogging, and plug fouling. Follow the Main Jet Setting
chart which is available at a Yamaha dealer carefully.
Proper carburetion adjustments will correct the air/fuel
ratio.
Standard main jet:
1
No.1 Carburetor (P.T.O. side)
# 145
2
,
3
No.2 and No.3 Carburetors (center and magne-
to side)
# 143.8
Main jet
4
Mixture Condition
Small No. Lean
Warm weather
High altitude
Large No. Rich
Cold weather
Low altitude
U8DY11.book Page 9 Friday, June 22, 2001 4:29 PM