Carry out preparations -
see 4.2.1.
•
Connect pressure hose of tester
1106 850 2905 to nipple on test
flange.
•
Close the vent screw (1) on
the rubber bulb.
Use rubber bulb to pump air into
the crankcase until the gauge
indicates a pressure of 0.5 bar
(7.25 psi). If this pressure re-
mains constant for at least 20
seconds, the crankcase or de-
compression valve, if fitted, is
airtight.
•
However, if the indicated press-
ure drops, the leak must be
located and the faulty part
replaced.
Note: To find the leak, coat the
suspect area with oil and
pressurize the crankcase again.
Bubbles will appear if a leak exists.
If the decompression valve is not
airtight, install a new one - see
4.8.
Repeat the pressure test.
Carry out the vacuum test - see
4.2.3.
After finishing the test, open the
vent screw and disconnect the
hose.
Remove the test flange.
Slacken off the muffler mounting
screws.
Pull out the sealing plate and
tighten down the screws to
8.5 Nm (6.3 lbf.ft).
Install carburetor - see 8.2.1 or
8.2.2.
Oil seals tend to fail when sub-
jected 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.
An additional test can be carried
out with the vacuum pump to
detect this kind of fault.
Carry out preparations -
see 4.2.1.
•
Connect the suction hose of
vacuum pump 0000 850 3501
to test flange nipple.
•
Close vent screw (1) on
pump cylinder.
•
Operate lever (2) until the gauge
(3) indicates a vacuum of 0.5 bar
(7.25 psi).
250RA016
VA
250RA017
VA
143RA046 V
A
1
250RA016
VA
2
50RA018
1
2
3
VA
4.2.2
Pressure Test
4.2.3
Vacuum Test
)6)5
Содержание FS 350
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