Instruction Manual

MS 171, MS 181, MS 181 C, MS 211, MS 211 C
English
45
Exhaust emissions are controlled by the
design of the fundamental engine
parameters and components (e.g.
carburation, ignition, timing and valve or
port timing) without the addition of any
major hardware.
General Information
The carburetor comes from the factory
with a standard setting.
This setting provides an optimum fuel-air
mixture under most operating
conditions.
Preparations
N Shut off the engine.
N Check the air filter and clean or
replace if necessary.
N Check the spark arresting screen
(not in all models, country-specific)
in the muffler and clean or replace if
necessary.
Standard Setting
N Turn high speed screw (H)
counterclockwise as far as stop (no
more than 3/4 turn).
N Turn the low speed screw (L)
clockwise as far as stop, then turn it
back 1/4 turn.
Adjusting Idle Speed
N Carry out the standard setting.
N Start and warm up the engine.
Engine stops while idling
N Turn the idle speed screw (LA)
clockwise until the chain begins to
run – then back it off 2 turns.
Saw chain runs while engine is idling
N Turn the idle speed screw (LA)
counterclockwise until the chain
stops moving – then turn it another
2 turns in the same direction.
WARNING
If the chain continues moving when the
engine is idling, have your saw checked
and repaired by your servicing dealer.
Erratic idling behavior, poor acceleration
(even though standard setting of low
speed screw is correct)
Idle setting is too lean
N Turn the low speed screw (L)
carefully counterclockwise, no
further than stop, until the engine
runs smoothly and accelerates well.
Engine Management Adjusting the Carburetor
H
L
533BA020 KN
LA
L
533BA021 KN