Some accidents and forced landings have been reported to us which have been caused by adding certain equipment to the engines out in the field. In most instances, the equipment added to the engine has not been approved by the airframe manufacturer or the engine manufacturer. Here are two of many examples reported to us:
One owner added a magnetic pickup to the engine oil drain plug which restricted oil flow to the oil suction screen, causing oil starvation to the engine, and resulted in failure.
Another owner installed an oil quick-drain plug on the engine sump of a plane with a retractable landing gear. When the gear was retracted, it knocked the protruding plug off, allowing the oil to escape and the engine to fail of oil starvation.
Operators in the field desiring to add any part to the engine should first consult with the engine and airframe manufacturer. Any addition or change of engine parts also calls for a careful ground run and inspection of the area of the engine after shutdown. Then the engine should be flown and the engine instruments carefully observed during the test flight. After the latter, the engine should again be inspected for oil or fuel leaks, etc., before flying with passengers. The Engine Operator’s Manual has a ground run checklist and a flight test record for such occasions.
The Textron Lycoming standard warranty statement summarizes our discussion in the following all inclusive statement:
"Textron Lycoming reserves the right to deny any warranty claim if it reasonably determines that the engine or part has been subjected to accident or used, adjusted, altered, handled, maintained, or stored other than as directed in your operator’s manual, or if non-genuine Textron Lycoming parts are installed in or on the engine and are determined to be a possible cause of the incident for which the warranty application is filed."