O.S. Engines FS-91 II FI - Manual (Page 22)

22
TROUBLESHOOTING
Problem Confirmation
Engine does not start
Engine operation is
unstable at low speeds
Engine operation is
unstable at high speeds
Engine stalls
Is the power turned on?
Are the connectors securely connected?
Is the lead wire broken?
Is the plug burned out?
Has Limit been set?
Are the connections correct?
Recheck the Buzzer sounds and LED display.?
Are the rubber dampers of the engine soft mount too soft?
Are the rubber dampers of the soft mount damaged?
Has the plug deteriorated?
Is there any sticking or abnormalities in the linkage?
Is the oil content of the fuel correct (not too much)?
Is the idling speed too low?
Is the check valve functioning properly?
Is the air control servo operating abnormally (hunting)?
If the sound of the engine remains unchanged when diving during
flight and stick response is lost, this indicates that there is too much
fuel being supplied to the engine. Try adjusting intermediate slow trim
in the (-) direction (right).
Is the air control linkage to weak so that the operation of the air valve
either stops or is delayed relative to the operation of the servo? (Try
using a thicker component for the linkage.)
Is the carburetor secured? (Check the carburetor retainer.)
Are the rubber dampers of the engine soft mount too soft?
Are the rubber dampers of the soft mount damaged?
Is the throttle linkage sticking?
Is the linkage too weak causing it to be affected by vibrations?
Is the check valve normal (Is thefuel tank pressurized?)
Is the servo malfunctioning or is the servo mount loose?
Is the propeller size correct?
Is the engine running at 9,500 rpm or higher?
Is there an abnormality in the engine soft mount (cracked)?
When there are occasional disturbances in engine speed when the
air-fuel mixture is rich at high speeds, there may be a problem with
the temperature sensor. Is an abnormal temperature (300˚C or
higher) displayed for Tmax Tmp?
Is the filter clogged?