Piston; Removal - Stihl MS 240 Instruction Manual

– Heat the area of the bearing seat
to about 150 °C (300 °F).
– Position the ball bearing so that
the centering ring (arrow) points
toward the oil pump.
: Push the ball bearing home as far
as stop (oil pump).
This operation must be carried out
quickly because the bearing
absorbs heat and begins to expand.
Check that the ball bearing is
properly seated and,
if necessary, use press arbor
1118 893 7200 to press it home
against the oil pump – too much
pressure may damage the oil pump.
– Remove the adjustable oil pump,
b 13.5
– Remove the non-adjustable oil
pump, b 13.4
– Install the crankshaft, b 8.6.1
– Install the oil seals,
b 8.3
– Reassemble all other parts in the
reverse sequence.
– Tightening torques, b 3.5
MS 240, MS 260, MS 260 C
8.7

Piston

8.7.1

Removal

Before removing the cylinder,
decide whether or not the
crankshaft has to be removed as
well, b 8.6
– Remove the cylinder, b 8.5
Note when removing the snap rings
that the installing tool 5910 890
2210 can only be applied to the
igniton side – the snap ring at the
clutch side must be installed first.
: Pry both hookless snap rings out
of their grooves by applying a
suitable tool to the recess
(arrow).
: Place the assembly drift (1)
1110 893 4700 in position.
1
: Use the assembly drift (2)
1110 893 4700 to push the piston
pin (1) out of the piston.
If the piston pin (1) is stuck, release
it by tapping the end of the drift (2)
lightly with a hammer.
Hold the piston steady during this
process to ensure that no jolts are
transmitted to the connecting rod.
: Remove the piston (1) from the
connecting rod.
1
– Inspect the piston rings and
replace if necessary, b 8.8
2
1
47