Examination After Engine Failure - Rotax 914 Series Maintenance Manual

2.3)

Examination after engine failure

In order to find possible causes of the failure, it is important to pass on all
available data. Observations on the aircraft and the engine suspension can also
be of help. It is important to pay particular attention to any of the following engine
phenomena to facilitate troubleshooting.
Engine runs erratically and misfires
May be caused by a failure in the fuel system (fuel supply, vapour locks,
contamination, float chamber venting, false air intake due to defective carburetor
flange, carburetor icing), or in the ignition system (shorting cable, electronic
module, spark plugs, wrong spark plug connection, grounding defect, charging
coil etc.).
Engine running out of round
May be caused by a failure in the ignition system or a fault in the carburetor (fuel
supply, contamination in float chamber or float needle valve, float chamber
venting, false air intake due to defective carburetor flange, engine temperature
too low, too lean carburetor jetting due to conditions prevailing in intake
silencer).
Cylinder head temperature too high
A rise in cylinder head temperature above normal operating limits (see
Operators Manual) is a clear signal for a failure in the cooling system:
- not enough coolant, bad venting, return valve is not working,
- radiator contaminated, radiator cap leaking, pressure relief valve is not
working,
- malfunction of water pump.
Unintended engine stoppage by seizing
May be caused by a failure in the lubrication system. Oil pressure too low or no
oil pressure due to oil shortage, contamination or bad venting of the oil system,
defective oil pump. This often causes the camshaft bearings and/or the conrod
bearings to seize up. The entire assembly must be dismantled, inspected and
repaired.
- The whole engine must be inspected, repaired or overhauled in accordance
with the BRP-Rotax instructions for continued airworthiness.
- Inspect all systems for correct functioning.
- Detailed inspection of affected engine components.
▲ WARNING: If one of the above failures should arise even only for a short
Effectivity 914 Series
Edition 1 / Rev. 0
BRP-Rotax
MAINTENANCE MANUAL
time, a detailed inspect is necessary. Localize trouble and
rectify.
05-50-00
page 7
May. 01/07