Carburetor - Rotax 447 UL SCDI Installation Manual

16)

Carburetor

The carburetor can be adjusted by jet replacement of various approved sizes, and
by adjusting idle air/fuel mixture screw, carb piston stop adjustment, needle sizes,
and needle position.
The air/fuel mixture at idle speed is adjusted by the air adjusting screw. The idle r.p.m.
is adjusted by the carburetor piston adjustment screw.
◆ NOTE:
◆ NOTE:
Replacement of parts should be done only after proper trouble shooting has been
carried out and then, by an experienced two cycle mechanic.
Ensure that throttle cable and linkage do not stick and that carb piston valve can be
fully opened and closed . Minor cable backlash can be adjusted at cable adjustment
screw and lock nut.
Be certain that throttle linkage is not affected by engine or airframe movement. This
will change throttle settings.
Air intake filtration and/or noise reduction devices must be in place for proper
carburation. See section on special operating conditions.
Special operating conditions, such as severe climate or altitude change may require
different jetting. Contact your dealer.
In no case should jet changes be made by unqualified persons or those who do not
have ROTAX technical information to do so.
▲ WARNING:
Effectivity: 447 UL SCDI, 503 UL DCDI, 582 UL DCDI /mod. 99
AIRCRAFT ENGINES
INSTALLATION MANUAL
These idle adjustments interact, so adjusting one may require
minor adjustment of the other.
On single carb engines, the carburetor must be in an exact right
angle position in relation to the crankshaft in both views from top
and from the intake side to ensure an equal mixture distribution to
both cylinders (see ill. below).
All parts liable to become loose have to be secured.
02813
02815
fig. 30
page 16 - 1
Initial issue, May 01/99