Vacuum Test - Stihl MS 201 Manual

MS 201
3
3
2
: Position the flange (1)
5910 850 4203 so that the
recesses fit over the bushings
and the screw (2) seals the
impulse hose (arrow).
: Fit the flange (1) 5910 850 4203,
insert and tighten down the
screws (3) firmly.
MS 201 T
1
3
2
: Position the flange (1)
5910 850 4203 so that the
recesses fit over the bushings
and the screw (2) seals the
impulse hose (arrow).
: Fit the flange (1) 5910 850 4203,
insert and tighten down the
screws (3) firmly.
30
6.2.2

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
1
there is no internal counterpressure.
A test can be carried out with pump
0000 850 1300 to detect this kind of
fault.
1 2
: Connect hose (1) of pump
0000 850 1300 to the nipple
(arrow).
: Push ring (2) to the left
– vacuum test.
3
: Operate the lever (3) until the
pressure gauge (4) 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.
If the pressure continues to rise
(reduced vacuum in engine), the oil
seals must be replaced, b 6.3.
– After finishing the test, push the
ring to the right to vent the pump.
– Continue with pressure test,
b 6.2.3
4
3
MS 201, MS 201 C, MS 201 T, MS 201 TC