GB–22
1.
Remove (4) mounting screws securing heater
box in place (Fig. 14 and 18).
2.
Pull choke knob off choke rod (Fig. 14).
3.
Remove carburetor heater box.
Note:
Skip steps 4 and 5 if the engine will
start and run.
4.
Power Adjusting Screw (Fig. 32)—Close screw
by gently rotating it clockwise until a slight
seating resistance is felt. Next, rotate power
adjusting screw 1 full
turn—360
_
—counterclockwise.
IMPORTANT: Do not close power adjusting
screw or idle mixture screw too tight because
the screw and seat will likely be damaged.
5.
Idle Mixture Screw (Fig. 32)—Close screw by
gently rotating it clockwise until a slight seating
resistance is felt. Next, rotate idle mixture screw
1-1/2 full turns counterclockwise.
6.
Start engine and let it warm up for
approximately 3 to 5 minutes; then move throttle
to FAST.
POTENTIAL HAZARD
•
Engine must be running so final adjustment of
the carburetor can be performed.
WHAT CAN HAPPEN
•
Personal injury is possible.
HOW TO AVOID THE HAZARD
•
Move auger/impeller drive and traction drive
controls to DISENGAGE.
•
Remember to keep hands, feet, face, and other
parts of your body or clothing away from
muffler, auger/impeller, discharge chute, and
any moving part(s).
POTENTIAL HAZARD
•
Engine exhaust contains carbon monoxide.
WHAT CAN HAPPEN
•
Carbon monoxide is an odorless, deadly
poison.
HOW TO AVOID THE HAZARD
•
Do not run engine indoors or in an enclosed
area.
7.
Rotate power adjusting screw (Fig. 32)
clockwise-in 1/8-turn at a time until engine
misses because of a lean gasoline mixture. Then
rotate screw counterclockwise-out 1/8-turn at
time until engine runs unevenly because of a rich
gasoline mixture. Next, rotate power adjusting
screw clockwise, back to the midpoint between
the rich and lean setting, so engine runs
smoothly.
Note:
Wait several seconds between each
1/8-turn setting so engine can adjust to
the new fuel mixture.
8.
Move throttle to idle speed. Next, rotate idle
speed screw until engine idles fast—1750 rpm.
9.
Rotate idle mixture screw (Fig. 32) clockwise-in
1/8-turn at a time until engine begins to miss
because of a lean mixture. Then rotate screw
counterclockwise-out 1/8-turn at a time until
engine runs unevenly because of rich mixture.
Next, rotate idle mixture screw clockwise, back
to the mid-point between rich and lean settings.
Note:
Wait several seconds between each
1/8-turn setting so engine can adjust to
the new fuel mixture.
10. Again, rotate idle speed screw (Fig. 32) until
engine idles at 1750 rpm.
11. Check carburetor adjustment by quickly moving
throttle from low speed to high speed. Engine
should accelerate without hesitation or
sputtering. If engine does not accelerate properly,