Interactive Learning
Component Identification
Learn which components belong to each engine system
Use the diagram and tables below to study which components belong to which system. For each inspection or procedure, confirm you can identify the relevant components before beginning work.
Engine Layout
Schematic — arrangement and cylinder numbering per D971-13, Section 11, paragraph 11-7. Not to scale, and not a mechanical drawing.
- Numbering runs rear to front. The right rear cylinder is No. 1, so the right bank carries 1 and 3. The left rear cylinder is No. 2, so the left bank carries 2 and 4.
- The banks are staggered. They are offset along the crankshaft rather than directly opposite each other, so that every connecting rod gets its own throw on the crankshaft.
- Firing order is 1 – 3 – 2 – 4 — the impulses alternate between banks rather than working down one side and back along the other.
- The accessory section is at the rear, driving both magnetos and the starter. The propeller mounts directly to the crankshaft at the front, with no reduction gearbox.
Fuel System
Section 2A
Fuel Tank
Stores the fuel supply
Fuel Line
Carries fuel from tank to carburetor
Fuel Strainer
Filters contaminants before the carburetor
Carburetor
Meters and mixes fuel with incoming air
Mixture Control
Pilot-adjustable fuel-air ratio for altitude
Ignition System
Section 2B
Left Magneto
Engine-driven spark generator — fires one plug per cylinder
Right Magneto
Second independent magneto — provides redundancy
Spark Plug
Produces the ignition spark; two per cylinder
Ignition Harness
High-voltage wires from magneto to each plug
Ignition Switch
Controls both magnetos (OFF / L / R / BOTH / START)
Lubrication System
Section 2C
Oil Sump
Wet-sump reservoir at the base of the engine
Oil Pump
Pressurizes oil for distribution throughout the engine
Oil Filter / Screen
Removes contaminants from circulating oil
Oil Pressure Gauge
Cockpit indication of oil pump output pressure
Cooling System
Section 2D
Cylinder Cooling Fins
Cast fins that transfer heat to passing airflow
Baffles
Sheet-metal panels directing airflow over the fins
Cowling
Outer enclosure that channels ram air through the baffle system
Induction System
Section 2E
Air Intake
Cowling opening that admits outside air
Intake Manifold
Ducts the air-fuel mixture to each cylinder's intake port
Carburetor Heat Control
Routes warm air to the carburetor to prevent/clear ice
Accessories
Section 2F
Starter
Electric motor that cranks the engine for starting
Alternator
Charges battery and powers electrical systems
Vacuum Pump
Powers gyroscopic flight instruments (where installed)