Stihl FC 90 - Piston

45Series 4180 Powerhead
: Rotate flywheel until mark (1) is in
line with screw head (2).
– Adjust valve timing,
b 7.4
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249RA130
2
1
– Remove the crankshaft,
b 7.8.3
Important:
Wear safety glasses when
working with spring washers and
snap rings.
: Ease the hookless snap ring out
of the groove.
VA
249RA088
: Use the assembly drift (2)
1110 893 4700 to push the piston
pin (1) out of the piston.
If the piston pin is stuck, release it
by tapping the end of the drift lightly
with a hammer. Hold the piston
steady during this process to ensure
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249RA089
2
1
that no jolts are transmitted to the
connecting rod.
: Inspect piston rings and replace if
necessary, b 7.8.5
Reassemble in the reverse
sequence.
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249RA090
7.8.4 Piston