Module 1 - ENGINE TROUBLESHOOTING

• Aircraft engine - require reliable parts and regular maintenance in order to operate safely
• To keep an aircraft engine in operating condition and ensure flight travel is safe and on schedule, aircraft mechanics perform:

  -          schedule maintenance

  -          make repairs

  -          overhauls

  -          complete inspections
• Aviation Mechanic - plays a vital part in the aviation industry
• Aviation Mechanic - the nature of his occupation requires that both initial training and subsequent in-service training to provide him with the skills and technical knowledge necessary to perform his work with the highest precision and efficiency possible
• Troubleshooting - referred to as a skill, in reality it is a process
• Good troubleshooting is systematic, but also fluid depending on the:

  -          time

  -          resources
• In some cases, it is best to start with the SIMPLEST OR LEAST EXPENSIVE SOLUTION and then, as necessary, move toward more COMPLEX OR MORE EXPENSIVE SOLUTIONS
• Whenever a fault or inconsistency is identified or comes to the attention of the technician, the TROUBLESHOOTING PROCESS BEGINS, no matter how easy or how complicated
• Resources – needs to be available to learn more about aircraft systems and the process of troubleshooting discrepancies
• Example of Resources:

  -          Information
• Manufacturer's Maintenance Publications - one of the best resources for troubleshooting information is found here
• Manufacturer maintenance manuals - typically include troubleshooting tables or logic flow charts that address common discrepancies; these present the symptoms as well as possible repair actions to perform
• Troubleshooting tables - are generally presented in a two or three column format
• In troubleshooting tables, the left-most column identifies the discrepancy, while another column lists possible causes for the discrepancy, the third column provides possible actions to resolve a given fault
• Logic Flow Chart - these charts are based on principles of the logic. The charts are designed to help you isolate a fault
• When a manufacturer table or chart is inadequate, you can study a schematic diagram to determine the logical place to start troubleshooting. Schematics are typically available for major components such as:

  -          Carburetors

  -          Alternators

  -          thrust reverser actuators

  -          systems including the fuel, ignition, lubrication, electrical, and hydraulic systems
• Schematic Diagrams - illustrate what parts are used in a particular component or system
• Schematic Diagram - is like a map, it helps you to determine the paths and connections of lines, cables, wiring, and passages within a system or component
• During an interview, consider the EXPERIENCE LEVEL of the pilot
• Troubleshooting - the step-by-step procedure used to determine the cause of a given fault and then select the best and quickest solution
• "Shotgun" Troubleshooting - removing and installing parts on a trial-and-error basis
• Logical And Systematic Approach - identify probable causes, and the appropriate steps to address the problem
• Six Steps of troubleshooting:

  1.       Symptom Recognition

  2.       Symptom Elaboration

  3.       Listing of Probable Faulty Functions

  4.       Localizing the Fault

  5.       Isolating the Fault to a Component

  6.       Failure Analysis
• The prerequisites for troubleshooting are to know the normal condition of the engine and to be able to identify when an engine is not running properly
• Symptom recognition - the first step in troubleshooting thus includes recognizing some condition of the engine that is not normal and recognizing to what extent the fault affects the performance of the engine
• Power Check - measures an engine's performance against the manufacturer's established standard
• 1700rpm – the rpm when magneto check is made
• RPM drop should not exceed 125 RPM on either magneto or show greater than 50 RPM differential between magnetos
• Malfunction – it happens when an engine quits firing completely when switched to one magneto
• List of Probable Faulty Functions:

  1.       Aircraft Sparkplug

  2.       Aircraft Magneto

  3.       Magneto Timing

  4.       Ignition Harness
• Test Equipment – use to measure or indicate the correct outputs for different system components