Stihl FS 40, Service Manual

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56 Series 4144 Components FC, FS, KM
Erratic idling behavior, engine
speed drops when swinging the
machine
Idle setting is too rich
– Turn the low speed screw (L)
clockwise (1/8 of a turn or 45° at
a time) until the engine runs
smoothly and accelerates well.
It is usually necessary to change the
setting of the idle speed screw
(LA)
after every correction to the low
speed screw
(L) .
Adjustment for operation at high
altitude
A minor correction may be
necessary if engine power is not
satisfactory when operating at high
altitude.
– Check standard setting.
– Warm up the engine with the
cutting tool mounted.
The drive shaft and cutting must
rotate freely.
– Turn the high speed screw (H)
clockwise (leaner) – no further
than stop.
Turn the adjusting screws only very
slightly. Even minor adjustments
can noticeably affect engine running
behavior.
If the setting is made too lean there
is a risk of engine damage as a
result of lack of lubrication and
overheating.
If the adjustments produce no
improvement, see the
troubleshooting charts for the
ignition system,
b
4.3, carburetor
and engine,
b
4.4,
b
4.5.
8.6 Removing and Installing
Throttle Cable (Loop
Handle)
– Press down the throttle lever until
the nipple (arrow) projects.
:
Turn the pin (2) until the slot is in
line with the throttle cable (1).
:
Remove the throttle cable (1).
– Remove the carburetor,
b
8.2
:
Take out the screw (arrow).
– Pull the retainer (1) with throttle
cable out of its seat.
545RA032 TG
1
2
545RA023 TG
1