Rotax 914 Series Maintenance Manual page 102

Effectivity 914 Series
Edition 1 / Rev. 1
MAINTENANCE MANUAL
Once the proper idling speed has been established, it is necessary to
check the operating range above the idle speed.
First establish that the engine is developing full take-off performance
or take-off rpm when selected in the cockpit. Then the setting of the
operating range (idle to full throttle) can be checked or adjusted.
Procedure:
Start and warm up engine (See Operators Manual). Select full power
and check that both pressure gauges are registering the same
readings. If the same reading is not made on both gauges, shut down
the engine and check that carburetor actuation effects full travel and
that starting carburetors (choke) are in the full off position.
If necessary, fit/modify the carburetor actuation as required to achieve
full power on both carburetors.
Once full power has been established on both carburetors, retard
the throttle and observe the pressure gauge settings. The pressure
gauges should show the same reading for both carburetors. Dis-
crepancies must be compensated for by adjusting the off idle ad-
justment (7) (see Fig. 24). The carburetor with the lower indication
must be advanced to match the higher one.
This is done by shutting down the engine and loosening the locknut
on the bowden cable and screwing the off idle adjustment in by 1/2
turn, then tightening the locknut and re-testing the engine.
Final idle speed adjustment may be required by resetting the idle speed
adjustment screws (2), see Fig. 24 accordingly. Equal adjustment must
be made on both carburetors.
Any major adjustments required necessitate replaced verification of all
parameters mentioned in this procedure.
Install compensation tube assy. on engine in reverse sequence of
removal. Any minor differences in balance at idle speed will be
compensated for.
■ CAUTION:
Follow the instructions of the instrument manufacturer.
Refit the screw plug M3,5 x 5 (pos. 8 Fig. 25) and hex.screws M6 x 6
(pos. 6 Fig. 27).
BRP-Rotax
12-00-00
page 28
Sept. 01/07