Vacuum Test - Stihl MS 200 Service Manual

: Fit the sealing plate (1)
0000 855 8106 between the
cylinder exhaust port and flange
and tighten down the screws
moderately.
The sealing plate must completely
fill the space between the two
screws.
– Remove the carburetor,
MS 200 b 14.2
MS 200 T b 14.2.1
2
Check that the sleeve (1) and
washer (2) are in place.
1
: MS 200 T: Take the screw (1) out
of the test flange.
30
1
: Fit the test flange 1128 850
4200 (1).
: Fit the nuts (arrows) and tighten
them down firmly.
1
8.2.2

Vacuum Test

Oil seals tend to fail when subjected
to a vacuum, i.e. the sealing lip lifts
away from the crankshaft during the
piston's induction stroke because
there is no internal counterpressure.
A test can be carried out with pump
0000 850 1300 to detect this kind of
fault.
1
: Connect suction hose (1) of
pump 0000 850 1300 to nipple
(arrow).
1
: Push ring (1) to the left.
: Operate the lever (2) until the
pressure gauge (arrow) indicates
a vacuum of 0.5 bar.
If the vacuum reading remains
constant, or rises to no more than
0.3 bar within 20 seconds, it can be
assumed that the oil seals are in
good condition.
However, if the pressure continues
to rise (reduced vacuum in the
engine),
the oil seals
must be replaced, b 8.3.
– After finishing the test, push the
ring to the right to vent the pump.
– Continue with pressure test,
b 8.2.3
MS 200, MS 200 T
1
2