APRILIA ATLANTIC 125 Workshop Manual page 88

FUEL SYSTEM
•
Remove the float chamber exhaust screw (3),
thoroughly wash and blow the float chamber. Make
sure to perfectly clean the pick-up pump intake and
delivery valve.
•
As these are one-way valves, gently blow with
compressed air into the intake valve working from the
float chamber inner side and into the exhaust valve
working from the pump piston seat.
•
Check the pick-up pump piston and its seat into the
float chamber for wear.
•
If this is the case, change the worn parts.
•
Check the pick-up pump piston return spring for wear.
•
Fit a new OR-seal and a new bellows seal. Refit the
piston unit onto the float chamber.
•
Fit a new OR-seal in the float chamber exhaust screw.
Tighten the screw.
•
To check screw proper sealing, pour a small quantity of
fuel into the float chamber.
•
Fit a new seal on the float chamber.
•
Fit the float chamber to the carburetor body. Tighten
the four screws.
•
Thoroughly wash and blow the flow adjuster screw. Fit
a new OR-seal.
•
Pre-assemble the following parts on the screw in the
following order: spring, washer and OR-seal.
•
Screw the flow screw on the carburetor body.
•
Screw final position will have to be defined according
to the exhaust gases analysis.
•
Prepare carburetor for adjustment by loosening the
screw by three turns starting from the closed position.
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ATLANTIC 125 - 200