Stihl FS 50 - 8.3 Leakage Test; 8.4 Servicing the Carburetor; 8.4.1 Metering Diaphragm; Manual Fuel Pump

47Series 4144 Components FC, FS, KM
8.3 Leakage Test
In the case of problems with the
carburetor or fuel supply system,
also check and clean or replace the
tank vent, b 8.8
The carburetor can be tested for
leaks with the pump 0000 850 1300.
– Remove the carburetor, b 8.2
: Push the pressure hose (1)
1110 141 8600 on to the
nipple (2) 0000 855 9200.
: Push the pressure hose with
nipple on to the carburetor’s fuel
stub (arrow).
165RA336 TG
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545RA010 TG
– Push the pressure hose of pump
0000 850 1300 on to the nipple.
: Push the ring (1) to the left and
pump air into the carburetor until
the pressure gauge (2) indicates
a pressure of about 0.8 bar
(80 kPa).
If this pressure remains constant,
the carburetor is airtight. However, if
it drops, there are three possible
causes:
1. The inlet needle is not sealing
(foreign matter in valve seat,
sealing cone of inlet needle
is damaged or
inlet control lever is sticking).
Remove to clean,
b 8.4.2
2. Metering diaphragm or gasket
damaged, replace if necessary,
b 8.4.1
3. Pump diaphragm or
gasket damaged, replace
if necessary, b 8.4.3
– After completing the test, push
the ring (1) to the right to vent the
system and then pull the fuel
hose off the carburetor.
– Use new fuel hoses and install
the carburetor, b 8.2
– Tightening torques, b 3.4
– Reassemble all other parts in the
reverse sequence.
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1
545RA205 TG
8.4 Servicing the Carburetor
8.4.1 Metering Diaphragm /
Manual Fuel Pump
– Remove the carburetor, b 8.2
: Take out the screws (arrows).
: Remove the complete flange (1).
: Remove the metering diaphragm
and gasket (1).
545RA183 TG545RA184 TG
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545RA185 TG
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