Stihl MS 311, Manual, Page: 72 / 94

71 MS 311, MS 391
12.5 Carburetor
– Remove the filter base, b 12.3
– Open the fuel tank cap and drain
the fuel tank.
– Collect the fuel in a clean
container, b 1
Disconnect the fuel hose only when
the tank cap is open.
: Push the fuel hose (1) back a little
– the fuel hose is disconnected.
: Remove the carburetor (1).
– Install a new fuel hose,
b 12.11.2
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1
4903RA224 TG
1
Installing
: Check that the sleeve (1) and
washer (2) are in place.
: Push the carburetor (1) into
position.
: The fuel hose must be located in
its seat (arrow).
: When positioning the carburetor,
make sure the stub (1) is pushed
into the fuel hose.
4903RA225 TG
1
2
4903RA226 TG
1
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1
: Shoulder (arrow) must fully
engage the intake manifold (1).
– Use STIHL press fluid to simplify
assembly, b 14
– Install the filter base, b 12.3
– Install the air filter, b 12.1
– Check operation.
– Reassemble all other parts in the
reverse sequence.
12.5.1 Leakage Test
In the case of problems with the
carburetor or fuel supply system,
also check and clean or replace the
tank vent,
b 12.10
The carburetor can be tested for
leaks with the pump
0000 850 1300.
– Remove the filter base, b 12.3
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1