6.7 Piston Rings; Crankshaft - Stihl MS 210 Service Manual

6.7 Piston Rings
– Pull the piston out of the cylinder
– b 6.6.
– Remove rings from the piston.
: Use a piece of old piston ring to
scrape the grooves clean.
: Install the new piston rings in the
grooves so that the radii face
upward.
– Install the piston – b 6.6.
MS 210, MS 230, MS 250
6.8

Crankshaft

2
: The crankshaft (1) and
connecting rod are an
inseparable unit. This means the
crankshaft must always be
replaced as a complete unit. The
needle bearing (2) is replaceable
on models MS 230 and MS 250.
When fitting a replacement
crankshaft, always install new ball
bearings and oil seals.
– Remove the piston – b 6.6.
: Remove the retaining ring
(arrow).
1
: Pull off the oil seals (1) and ball
bearings (2).
: Heat ball bearing to approx. 50°C
(120°F) and, with closed side
facing outwards, push it on to the
crankshaft stub as far as stop.
If the crankshaft has been removed,
the oil seals used in production
(9639 003 1585 with rigid housing)
may be installed.
– Lubricate sealing lips of oil seals
with grease – b 13.
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