Stihl MS 650

85MS 650, MS 660
Vacuum test
: Connect vacuum pump (1)
0000 850 3501 to fuel hose (2)
and create vacuum in fuel tank.
Equalization of pressure takes
place via the tank vent. There must
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2
be no build-up of vacuum in the
tank. In the event of a malfunction,
install a new tank vent.
Pressure test
: Connect carburetor and
crankcase tester 1106 850 2905
(1) to the fuel hose.
– Squeeze the rubber bulb until the
the pressure gauge shows a
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reading of 0.5 bar. If this pressure
remains constant for at least 20
seconds, the tank, including the
tank vent, is airtight. If it drops,
the leak must be found and the
defective part replaced.
– Clean area around the tank vent.
Version with connector and hose
: Pry off the connector (1).
1
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: Remove the filter element (1).
1
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: Pull the valve (1) into the tank.
Installing
– Place the valve in the tank and
carefully pull it into position from
the carburetor housing.
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Reassemble all other parts in the
reverse sequence
– Test tank for leaks – b 12.6