Servicing - Stihl MS 290 Manual

: Swing the oil pump (1) forwards a
little.
: Carefully remove oil pump (1),
pulling the elbow connector (2)
off the engine housing nipple at
the same time.
– Remove the muffler, b 6.1
: Fit new O-ring (arrow) on engine
housing nipple.
Install in the reverse sequence.
MS 290, MS 310, MS 390
2
1
: Hold the elbow connector at a
slight angle and fit the oil pump.
: Push the elbow connector onto
the engine housing nipple
(arrow).
The elbow connector must snap
audibly into position.
– Line up the oil pump.
Install all other parts in the reverse
sequence.
When fitting the cover washer,
make sure the word "TOP" faces
outwards.

10.4.2 Servicing

1 2 3 2
Check the suction hose and pickup
body are clean before dis-
assembling the oil pump, b 10.1.
– Remove the oil pump, b 10.4.1
: Turn the elbow connector (6)
forwards through 90 degrees and
pull it out of the oil pump (4).
: Take the O-ring (5) off the elbow
connector.
: Use a 2 mm drift to drive out the
spring pin (7).
: Pull the control bolt (9) out of the
housing and remove the O-rings
(8).
: Remove the pump piston (1) with
spring (3) and washers (2).
– Clean all parts with standard
solvent-based degreasant
containing no chlorinated or
halogenated hydrocarbons,
b 13.
Install in the reverse sequence.
6
5
4
7
8
9
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