Stihl MS 311 User Manual - Page 77

Air Valve, Position of throttle shutter/air, valve, Levers on Throttle Shaft, Installing

Page 77 highlights

12.6.4 Air Valve 12.6.5 Levers on Throttle Shaft Air valve shaft stiff or air valve cannot be closed or opened properly: The air valve matches the end cover. If it is damaged, the complete end cover must be replaced. - Carburetor troubleshooting, b 3.6 Position of throttle shutter/air valve The correct position of the air valve can be checked visually as follows. - Throttle shutter in idle position - air valve fully closed. - Throttle shutter in idle position / full throttle position - air valve closed / wide open. 1 3 2 4 5 4903RA192 TG Lever (1) must butt against lever (2) and engage lever (3). Lever (5) must engage lever (2) for cold and warm starts - the choke lever (5) returns to the idle position when the throttle is opened. - Screw (4) must be tightened down firmly. - Remove the carburetor, b 12.5 - Carburetor troubleshooting, b 3.6 4 3 1 2 : Take out the screw (1). - Relieve tension of the torsion spring (2) and remove the lever (3). 4903RA194 TG - Throttle shutter in full throttle position - air valve wide open. - Pull off the torsion spring (2) and lever (4). - Throttle shutter in cold start position l - air valve fully closed. - Throttle shutter in warm start position n - air valve open about 5° The air valve must move freely in both directions (open and closed) and always return to the idle position. The air valve is fully closed in the idle position. The torsion springs (arrows) must be preloaded and attached to the levers. 4903RA193 TG Installing 1 : Push the lever (1) onto the throttle shaft as shown (arrow). 4903RA195 TG 76 MS 311, MS 391

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76
MS 311, MS 391
12.6.4
Air Valve
Air valve shaft stiff or air valve
cannot be closed or opened
properly:
The air valve matches the end
cover. If it is damaged, the complete
end cover must be replaced.
Carburetor troubleshooting,
b
3.6
Position of throttle shutter/air
valve
The correct position of the air valve
can be checked visually as follows.
Throttle shutter in idle position
– air valve fully closed.
Throttle shutter in idle position /
full throttle position – air valve
closed / wide open.
Throttle shutter in full throttle
position – air valve wide open.
Throttle shutter in cold start
position
l
– air valve fully closed.
Throttle shutter in warm start
position
n
– air valve open about 5°
The air valve must move freely in
both directions (open and closed)
and always return to the idle
position.
The air valve is fully closed in the
idle position.
Lever (1) must butt against lever (2)
and engage lever (3).
Lever (5) must engage lever (2) for
cold and warm starts
– the choke lever (5) returns to the
idle position when the throttle is
opened.
Screw (4) must be tightened
down firmly.
The torsion springs (arrows) must
be preloaded and attached to the
levers.
4903RA192 TG
1
3
2
4
5
4903RA193 TG
12.6.5
Levers on Throttle Shaft
Remove the carburetor,
b
12.5
Carburetor troubleshooting,
b
3.6
:
Take out the screw (1).
Relieve tension of the torsion
spring (2) and remove the lever
(3).
Pull off the torsion spring (2) and
lever (4).
Installing
:
Push the lever (1) onto the
throttle shaft as shown (arrow).
4903RA194 TG
1
4
2
3
4903RA195 TG
1