80 MS 171, MS 181, MS 211
– Check the air valve shaft (1) and
torsion spring (2) and replace if
necessary.
– Note installed position (arrow) of
torsion spring.
: Push the air valve shaft (1) into
the valve body (arrow).
– Apply thin coating of oil to air
valve shaft and guides, b 16
: Position leg of torsion spring
against web (arrow) on valve
body.
533RA330 TG
1
2
1
533RA331 TG533RA332 TG
: Fit the E-clip (1).
: Turn the air valve shaft (1)
counterclockwise until the its flat
side (arrow) points upwards – air
valve shaft is now preloaded.
– Hold the air valve shaft in the
preloaded position.
: Slide the air valve (1), with the
hole (2) on the left and the
marking visible, into the slot in the
shaft.
533RA333 TG
1
1
533RA334 TG
533RA335 TG
2
1
– Coat the screw with thread-
locking adhesive, b 16
: Insert new screw (1) and tighten
moderately.
– Close the air valve (2) and center
it in the valve body’s bore.
– Tighten down the screw firmly.
– Check valve’s freedom of
movement.
– Reassemble all other parts in the
reverse sequence.
14.4.7 Choke Shaft / Choke
Shutter
Choke shaft stiff or choke shutter
cannot be closed or opened
properly:
– Remove the carburetor, b 14.3
– Carburetor troubleshooting,
533RA336 TG
1
2