85
MS 271 C, MS 291 C
– 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 (2).
Models with manual fuel pump
:
Push the new fuel hose (1) onto
the nipples (arrows).
All models
– Install the filter base,
b
12.3
– Install the air filter,
b
12.1
– Check operation.
– Reassemble all other parts in the
reverse sequence.
5902RA372 TG
2
1
2710RA273 TG
1
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 carburetor,
b
12.5
:
Push the fuel hose (1)
1110 141 8600 onto the
nipple (2) 0000 855 9200.
:
Push the fuel hose with nipple
onto the carburetor’s fuel
stub (arrow).
– Push the pressure hose of pump
0000 850 1300 onto the nipple.
2710RA333 TG
1
2
2
1
5902RA380 TG
:
Push the ring (1) to the right 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. Metering diaphragm or gasket
damaged, replace if necessary,
b
12.6.1
2. 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
12.6.2
3. Pump diaphragm or
gasket damaged, replace
if necessary,
b
12.6.3
– Test the tank vent if necessary,
b
12.10.1
– After completing the test, push
the ring (1) to the left to vent the
system and then pull the fuel
hose off the carburetor.
– Install the filter base,
b
12.3
– Reassemble all other parts in the
reverse sequence.