PROPELLER 1. GENERAL The airplane employs a 3 blade, constant speed, non-feathering propeller. The blades (composite or aluminum) are mounted in an aluminum hub which contains the pitch changing mechanism consisting of a piston/cylinder, piston rod, and blade actuating components. Serials 22-0002 & subs: For propeller speed adjustment, a propeller control cable is terminated on a cam plate which is mounted to the throttle control lever. This connection mechanically adjusts the propeller speed by increasing oil pressure from an engine mounted governor to move the blades into high pitch or reduced RPM. A spring and centrifugal twisting moment of the blades moves them to low pitch in the absence of governor oil pressure. Under this arrangement, the propeller is set to 2700 RPM for full forward throttle takeoff and climb, 2500 RPM for mid to full throttle cruise, and approximately 1900 RPM at lower power. Serials 22T-0001 & subs: There is no propeller control cable installed on these airplanes. Propeller speed is set to 2500 RPM. Increasing oil pressure from an engine mounted governor moves the blades into high pitch or reduced RPM. A spring and centrifugal twisting moment of the blades moves them to low pitch in the absence of governor oil pressure. All Page 1
5 1 3 4 6 7 8 9 10 11 12 2 15 14 13 17 16 LEGEND 1. Shaft O-Ring 2. Mounting Stud 3. Engine Flange 4. Spinner Bulkhead 5. Blade 6. Blade Retention Bearing 7. Hub 8. Pitch Return Spring 9. Piston 10. Oil 11. Cylinder 12. Low Pitch Stop 13. Spinner Dome 14. Pitch Change Rod 15. Fork 16. Grease Fitting 17. Balance Wire SR22_MM61_2021 Page 2 Figure 1 Propeller Schematic - Serials w/ Hartzell Propeller (Sheet 1 of 2) Serials w/ Hartzell Propeller
5 18 4 19 6 20 7 21 9 12 2 13 8 23 22 11 LEGEND 2. Mounting Stud 4. Spinner Bulkhead 5. Blade 6. Blade Retention Bearing 7. Hub 8. Pitch Return Spring 9. Piston 11. Cylinder 12. Low Pitch Stop 13. Spinner Dome 18. Blade O-Ring 19. Blade Shim Pack and Retaining Ring 20. Split Retainer 21. High Pitch Stop 22. Blade Actuating Pin 23. Balance Weights Serials w/ McCauley propeller Figure 1 Propeller Schematic - Serials w/ McCauley propeller (Sheet 2 of 2) SR22_MM61_1760 Page 3
POWER LEVER MIXTURE LEVER MIXTURE THROTTLE ALT AIR INDUCTION HUB SPINNER FIREWALL GOVERNOR SR22_MM61_1480B Page 4 Figure 2 Propeller Control - Serials 22-0002 & subs (Sheet 1 of 2) Serials 22-0002 & subs
POWER LEVER MIXTURE LEVER MIXTURE THROTTLE HUB FIREWALL SPINNER SR22_MM61_3237 Serials 22T-0001 & subs Figure 2 Propeller Control - Serials 22T-0001 & subs (Sheet 2 of 2) Page 5
2. TROUBLESHOOTING Trouble Probable Cause Remedy Surging propeller. Governor out of adjustment. Engine speed varies with attitude or airspeed. Decrease in engine speed while increasing airspeed. Decrease in engine speed while decreasing airspeed. Increase in engine speed while decreasing airspeed. Increase in engine speed while increasing airspeed. Propeller goes to uncommanded low pitch. Oil leakage at engine flange/hub interface. Oil leakage at other locations. Serials 22-0002 & subs: Tachometer does not indicate 2700 RPM with power lever in full forward position. Serials 22-0002 & subs: Tachometer does not indicate 2500 RPM with power lever in engine cruise position. Serials 22T-0001 & subs: Tachometer does not indicate 2500 RPM with power lever in full forward position. Air in propeller governor oil body. Governor not properly controlling propeller blade angle. Friction in propeller. Governor is excessively increasing oil volume. Governor is not reducing oil volume. Governor is excessively decreasing oil volume. Governor is not increasing oil volume. Propeller piston seal leaking oil to opposite side of piston. Loss of propeller oil pressure. Damaged O-ring seal between engine and propeller. Mounting nuts not tight. Defective seals or incorrect assembly. Governor out of adjustment. Governor control cable out of adjustment. Governor out of adjustment. Cycle propeller through pitch range several times. Inspect propeller and make necessary adjustments. Remove propeller from aircraft, disassembly, clean, and replace propeller seals. (Refer to 61-10) Inspect governor pressure relief valve, governor drive, engine oil supply, engine transfer bearing for leakage. Replace O-ring. (Refer to 61-10) Clean mating surface and tighten nuts properly. (Refer to 61-10) Repair or replace seals as required. Perform Adjustment/Test - Governor Rigging and Low-Pitch Stop Adjustment. (Refer to 61-20) Perform Functional Test - Engine Cruise RPM. (Refer to 61-20) Perform Adjustment/Test - Governor Rigging. (Refer to 61-20) Page 6 All