Standard Setting - Stihl MS 200 Service Manual

14.5.2 Standard Setting

The limiter caps must not be
removed for the standard setting.
Always perform the following steps
before carrying out any
adjustments:
– Troubleshooting, b 4.6
– Check chain tension and adjust if
necessary, b 5
– Inspect the spark arresting
screen (if fitted) and clean or
replace if necessary. b 8.1
– Check the air filter and clean or
replace if necessary, b 14.1
Standard Setting
– Shut down the engine.
– Turn the high speed screw (H)
slowly counterclockwise as far as
stop, but not more than a 3/4 turn.
– Turn the low speed screw L
slowly clockwise as far as stop,
then turn it back 1 full turn.
Check running behavior:
The engine must idle and
accelerate smoothly.
104
Adjusting engine idle speed
– Carry out standard setting.
– Allow engine to warm up.
Engine stalls at idle speed
– Turn the idle speed screw (LA)
clockwise as far as stop or until
the saw chain begins to move.
Then turn it back one quarter
turn.
Saw chain rotates at idle speed
– Turn the idle speed screw (LA)
counterclockwise until the chain
stops running, then turn it back
one quarter turn.
Erratic idling behavior, poor
acceleration
(although standard setting is
correct)
Idle setting too lean.
– Allow engine to warm up.
– Turn low speed screw (L)
counterclockwise until the 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).
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.
– Allow engine to warm up.
– 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, carburetor and
engine, b 4.5, b 4.6 and b 4.7
MS 200, MS 200 T