Stihl MS 311, Manual, Page: 36 / 94

35 MS 311, MS 391
: Fit the screws (arrows).
: Tighten down the screws
(arrows) in an alternate pattern.
– Reassemble all other parts in the
reverse sequence.
6.6 Bearings / Crankshaft
– Remove the cylinder, b 6.5
– Remove the crankshaft and pull
off the oil seals, b 6.5
– Remove the piston, b 6.7
: Pull the ball bearing (1) off the
tapered crankshaft stub.
4903RA072 TG
1
4903RA082 TG
: Pull the ball bearing (1) off the
straight crankshaft stub.
: The crankshaft (1), connecting
rod (2) and needle bearing form
an inseparable unit.
When fitting a replacement
crankshaft, always install new ball
bearings and oil seals.
Before installing, clean the
crankshaft,
b 14
Heated ball bearings must be
installed quickly because the
crankshaft stubs absorb heat and
expand.
1
4903RA083 TG
4903RA084 TG
2
1
– Heat the bearing inner race to
about 150°C (300°F).
: Push the ball bearing onto the
straight crankshaft stub as far as
stop.
– Heat the bearing inner race to
about 150°C (300°F).
: Push the ball bearing onto the
tapered crankshaft stub as far as
stop.
– Lubricate the needle bearing with
oil.
– Install the piston, b 6.7
– Install the crankshaft and oil
seals, b 6.5
1
4903RA085 TG
1
4903RA086 TG