Husqvarna TrioBrake 550XPG Workshop Manual page 43

Alternative 2; AT-12 carburettor
7
Dismantle the metering cover G and carefully
remove the gasket H, diaphragm I, spiral J and
gasket K.See figure 39.
8
Unscrew screw N and remove needle valve M with
lever arm O, shaft L and spring P. See figure 39.
9
To access the pump diaphragm and the inlet
screen, first remove the air throttle housing from
the pump cover by unscrewing the two screws Z.
Then remove the pump cover. See figure 40.
10
Use a needle or similar device and carefully pull up
the fuel screen U. See figure 40.
11
If necessary, dismantle throttle valve R and choke
valve S and air valve Q, and remove the shafts
with lever arms and springs (see figure 40). Before
removing the screws attaching the valves, cut off
the ends of each screw.
12
If necessary, dismantle the AutoTune Y unit. See
figure 40.
L
M
N
Fig 39
Repair Instructions
G
H
I
J
K
O
P
43
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