Airworthiness Directive · Amendment 39-17535 · BRP-Powertrain GmbH & Co KG Rotax Reciprocating Engines
BRP-Powertrain GmbH & Co KG Rotax Reciprocating Engines
This AD applies to the following BRP Powertrain GmbH & Co KG Rotax reciprocating engines:
(1) Rotax 912F from serial number (S/N) 4,413.013 to S/N 4,413.019, inclusive.
(2) Rotax 912S, from S/N 4,924.468 to S/N 4,924.543, inclusive.
(3) Rotax 914F, from S/N 4,421.156 to S/N 4,421.177, inclusive.
(4) All Rotax 912F, 912S, and 914F engines with cylinder head assembly, part number (P/N) 623682 or P/N 623687, supplied by BRP-Powertrain between January 31, 2013, and May 28, 2013, installed.
We are superseding an existing airworthiness directive (AD) for all BRP-Powertrain GmbH & Co KG Rotax model 912 F2; 912 F3; 912 F4; 912 S2; 912 S3; 912 S4; 914 F2; 914 F3; and 914 F4 reciprocating engines. That AD required a one-time visual inspection for excessive oil or carbon deposits on the cylinder No. 2 and No. 3 (\2/3\) spark plug center and grounding electrodes, and if found, replacement of the cylinder head before further flight. This AD was prompted by a report that additional engine cylinder heads are likely to be affected. We are issuing this AD to prevent excessive oil consumption, which could result in an in-flight engine shutdown, forced landing, and damage to the airplane.
(1) Within 5 flight hours or 20 days after the effective date of this AD, whichever occurs first, perform a one-time visual inspection of the center and grounding electrodes of both top and bottom spark plugs on cylinder 2 and cylinder 3, for unusual deposits of excessive oil or carbon deposits. Any excessive oil or carbon deposits indicate the cylinder head is not manufactured to proper specification and is leaking oil into the combustion chamber.
(2) Before further flight, replace cylinder heads not manufactured to proper specification.
(3) From the effective date of this AD, installation on an engine of an affected spare cylinder head assembly part number (P/N) 623682 or P/N 623687, supplied by BRP-Powertrain between January 31, 2013, and May 28, 2013, is prohibited unless the engine, with the spare cylinder head installed, is test run for at least 20 minutes and the inspection called out in paragraph (e) (1) of this AD is accomplished. If the cylinder head fails the inspection required by paragraph (e) (1) of this AD, remove the cylinder head assembly before further flight.
For the purpose of this AD, unusual deposits (excessive carbon or oil) is when:
(1) Carbon is a visual buildup of dark carbon deposits on the center and grounding electrodes as well as the immediate surrounding area, and
(2) Excessive oil is a visual buildup indicated by the presence of oil on the center and grounding electrodes as well as the immediate surrounding area, giving a wet appearance.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines
