Operation Manual

45MS 650, MS 660
English / USA
Adjusting Idle Speed
Engine stops while idling
: Carry out standard setting on low
speed screw (L).
: Turn the idle speed screw (LA)
clockwise until chain begins to run –
then back it off
1
/
4
turn.
Chain runs when engine is idling
: Carry out standard setting on low
speed screw (L).
: Turn the idle speed screw (LA)
counterclockwise until chain begins
to run – then turn it another
1
/
4
turn
in the same direction.
Erratic idling behavior, poor
acceleration
(even though standard setting of low
speed screw is correct)
Idle setting is too lean.
: Turn the low speed screw (L)
counterclockwise (no further than
stop) until engine runs and
accelerates smoothly.
It is usually necessary to change the
setting of the idle speed screw (LA)
after every correction to the low speed
screw (L).
Fine Tuning for Operation at High
Altitude
A slight correction of the setting may be
necessary if engine power is not
satisfactory when operating at high
altitude:
: Check the standard setting.
: Warm up the engine.
: Turn high speed screw (H) slightly
clockwise (leaner). On models with
H =
3
/
4
, turn no further than stop.
If the setting is too lean there is
a risk of engine damage due to
insufficient lubrication and
overheating.
LA
L
137BA024 KN