Stihl MS 311 Manual

81MS 311, MS 391
Standard Setting
– Shut off 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.
Adjusting engine idle speed
– Carry out standard setting.
– Warm up the engine.
Engine stops while idling
– Turn the idle speed screw (LA)
clockwise until the chain begins
to run, then turn it back 1/2 a turn.
Saw chain runs while engine is
idling
– Turn the idle speed screw (LA)
counterclockwise until the chain
stops running, then turn it back
1/2 a turn.
Erratic idling behavior, poor
acceleration
(although standard setting is
correct)
Idle setting too lean.
– Warm up the engine.
– Turn the 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 (L)
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.
– 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.
12.8 Carburetor Carrier
– Remove the carburetor, b 12.5
: Take out the sleeve (2) and
washer (1).
– Disconnect fuel suction hose
from the carburetor carrier.
: Push the manifold flanges (1) out
of the carburetor carrier (2) in the
direction of the cylinder.
– Remove the carburetor
carrier (2).
4903RA230 TG
1
2
4903RA231 TG
1
1
2

Stihl MS 311 Specifications

General

Oil tank capacity	0.348 L
Fuel tank capacity	0.6 L
Power source	Gasoline

Weight and Dimensions

Weight	6200 g