17 TUNING THE ENGINE
17.5
122
Carburetor – adjusting the idle speed
E00370-10
–
Screw idle air adjusting screw
–
Turn the idle air adjusting screw to the specified basic setting.
Info
The basic setting of the carburetor is specified in the
technical data.
–
Run the engine until warm.
Guideline
Warm-up time
–
Connect special tool.
Tachometer (45129075000)
Danger
Danger of poisoning Exhaust gases are toxic and inhal-
ing them may result in unconsciousness and death.
–
Always make sure there is sufficient ventilation
when running the engine.
–
Use an effective exhaust extraction system when
starting or running the engine in an enclosed
space.
–
Adjust the idle speed with adjusting screw
Guideline
Choke function deactivated – The choke lever is pushed in
to the stop. (
p. 20)
Idle speed
–
Turn idle air adjusting screw
tion until the idle speed begins to fall.
–
Note the position and turn the idle air adjusting screw slowly
counterclockwise until the idle speed again begins to fall.
–
Adjust to the point between these two positions with the high-
est idle speed.
Info
If there is a big engine speed rise, reduce the idle
speed to a normal level and repeat the above steps.
If the procedure described here does not lead to sat-
isfactory results, the cause may be a wrongly dimen-
sioned idling jet.
If you can turn the idle air adjusting screw to the end
without any change of engine speed, mount a smaller
idling jet.
After changing the jet, start from the beginning with
the adjusting steps.
Following extreme air temperature or altitude changes,
adjust the idle speed again.
1
all the way in.
≥ 5 min
2
.
1,400 ... 1,500 rpm
1
slowly in a clockwise direc-