Stihl MS 192 T Manual page 29

8.2.1 Preparations
– Remove the sprocket cover and
bar and chain, b 5.1
– Set the piston to the top dead
centre. This can be checked
through the inlet port.
– Fit the spark plug and tighten it
down firmly.
: Undo the screws (arrows).
: Fit the sealing plate (1)
0000 855 8106 between the
muffler and cylinder exhaust port
and tighten down the screws
moderately.
The sealing plate must fill the full
width between the screws.
– Remove the carburetor, b 14.2
28
2
: Ensure that the sleeve (1) and
washer (2) are in place.
1
1
: Remove the socket head screw
(1) from the test flange
1128 850 4200.
1
– Fit the test flange
1128 850 4200 (1).
: Screw on the nuts (arrows) and
tighten them down firmly.
8.2.2 Vacuum test
Oil seals tend to fail when subjected
to a vacuum. In other words, the
sealing lip lifts away from the
crankshaft during the piston's
induction stroke because there is no
internal counterpressure.
1
An additional test can be carried out
with the vacuum pump to detect this
kind of fault.
1
: Connect the suction hose (1) of
the vacuum pump
0000 850 3501 to the nipple
(arrow).
1 2
: Close the vent screw (1).
: Operate lever (2) until the
pressure gauge (arrow) indicates
a vacuum of 0.5 bar.
MS 192 T