Leakage Test; Repairing The Carburetor; Metering Diaphragm - Stihl GS 461 Manual

10.3.1 Leakage test

The tank vent must also be checked
and replaced if problems develop
with the carburetor or fuel supply,
b 10.7
The carburetor can be tested for
leaks with the pump
0000 850 1300.
– Remove the carburetor, b 10.3
1 3
2
: Push the fuel line (1)
1110 141 8600 onto the double
connector (2)
0000 855 9200 and then push
onto the fuel port (3)
2
1
– Push pressure hose of the pump
0000 850 1300 onto the double
connector
: Push ring (1) to the right and
pump air into the carburetor until
the pressure gauge (2) shows a
pressure of approx. 0.8
bar (80 kPa)
GS 461
If this pressure remains constant,
the carburetor is airtight. However, if
the pressure drops, this may have
the following three causes:
1. The inlet valve is not sealing
(foreign objects in the valve
seat,
sealing cone of the inlet needle
is damaged or
inlet control lever is sticking),
remove to clean,
b 10.4.2 or b 10.7.1
2. Metering diaphragm or gasket is
damaged, replace if necessary,
b 10.4.1 or b 10.7.1
3. Pump diaphragm or
gasket damaged,
replace if necessary, b 10.4.3
or
b 10.7.1
– After completing the test, slide
ring (1) to the left and vent the
system, then disconnect fuel line
from elbow connector of
carburetor
– Install filter base, b 10.2
– Reassemble remaining parts in
reverse order
10.4

Repairing the carburetor

10.4.1 Metering diaphragm

– Troubleshooting, b 3.6
– Remove the carburetor, b 10.3
– Check sleeve, remove and
replace if necessary
2 1
1
1
: Unscrew the screws (1) and
remove the end cover (2)
If the gasket and diaphragm are
stuck to the carburetor, they must
be removed very carefully
1 2
: Carefully separate the metering
diaphragm (1) and gasket (2)
The diaphragm material is
subjected to continuous alternating
stresses and eventually shows
signs of fatigue. In other words, the
diaphragm distorts and swells and
must be replaced.
– Examine the metering diaphragm
for signs of damage and wear,
replace the gasket.
1
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