PART 5 LEP

PARTSECTION PAGE DATE

LEP 1 Jul 01/20052 Jul 01/2005

Contents 1 Jul 01/20052 Jul 01/20053 Jul 01/20054 Jul 01/20055 Jul 01/20056 Jul 01/20057 Jul 01/20058 blank Jul 01/2005

List ofFigures

1 Jul 01/20052 Jul 01/2005

List ofTables

1 Jul 01/20052 blank Jul 01/2005

Section 1 5-1-1 Jul 01/20055-1-2 May 23/20035-1-3 May 23/20035-1-4 May 23/20035-1-5 May 23/20035-1-6 May 23/20035-1-7 May 23/20035-1-8 May 23/20035-1-9 May 23/2003

5-1-10 May 23/20035-1-11 May 23/20035-1-12 May 23/20035-1-13 May 23/20035-1-14 May 23/20035-1-15 May 23/20035-1-16 May 23/20035-1-17 May 23/20035-1-18 May 23/20035-1-19 May 23/20035-1-20 May 23/20035-1-21 May 23/20035-1-22 May 23/20035-1-23 May 23/2003


5-1-24 May 23/20035-1-25 May 23/20035-1-26 May 23/20035-1-27 May 23/20035-1-28 May 23/20035-1-29 May 23/20035-1-30 May 23/20035-1-31 May 23/20035-1-32 May 23/20035-1-33 May 23/20035-1-34 May 23/20035-1-35 May 23/20035-1-36 May 23/20035-1-37 May 23/20035-1-38 May 23/20035-1-39 May 23/20035-1-40 May 23/20035-1-41 May 23/20035-1-42 May 23/20035-1-43 May 23/20035-1-44 May 23/20035-1-45 May 23/20035-1-46 May 23/20035-1-47 May 23/20035-1-48 May 23/20035-1-49 May 23/20035-1-50 May 23/20035-1-51 May 23/20035-1-52 May 23/20035-1-53 May 23/20035-1-54 May 23/20035-1-55 May 23/20035-1-56 May 23/20035-1-57 May 23/20035-1-58 May 23/20035-1-59 May 23/20035-1-60 May 23/20035-1-61 May 23/20035-1-62 May 23/20035-1-63 May 23/20035-1-64 May 23/2003

PRATT & WHITNEY CANADAOVERHAUL MANUAL

MANUAL PART NO. 3011403

LIST OF EFFECTIVE PAGES

PART 5 LEP Jul 01/2005


5-1-65 May 23/20035-1-66 May 23/20035-1-67 May 23/20035-1-68 May 23/20035-1-69 May 23/20035-1-70 May 23/20035-1-71 May 23/20035-1-72 May 23/20035-1-73 May 23/20035-1-74 May 23/20035-1-75 May 23/20035-1-76 May 23/20035-1-77 May 23/20035-1-78 May 23/20035-1-79 May 23/20035-1-80 May 23/20035-1-81 May 23/20035-1-82 May 23/20035-1-83 May 23/20035-1-84 May 23/20035-1-85 May 23/20035-1-86 May 23/20035-1-87 May 23/20035-1-88 May 23/20035-1-89 May 23/20035-1-90 May 23/20035-1-91 May 23/20035-1-92 May 23/20035-1-93 May 23/20035-1-94 May 23/20035-1-95 May 23/20035-1-96 May 23/20035-1-97 May 23/20035-1-98 May 23/20035-1-99 May 23/2003

5-1-100 May 23/20035-1-101 May 23/20035-1-102 May 23/20035-1-103 May 23/20035-1-104 May 23/20035-1-105 May 23/2003


5-1-106 May 23/20035-1-107 May 23/20035-1-108 May 23/20035-1-109 May 23/20035-1-110 May 23/20035-1-111 May 23/20035-1-112 May 23/20035-1-113 May 23/20035-1-114 May 23/20035-1-115 May 23/20035-1-116 May 23/20035-1-117 May 23/20035-1-118 May 23/20035-1-119 May 23/20035-1-120 May 23/20035-1-121 Jul 01/20055-1-122 Jul 01/20055-1-123 May 23/20035-1-124 blank May 23/2003



LIST OF EFFECTIVE PAGES

PART 5 LEP Jul 01/2005

PART 5 - DISASSEMBLY

INTRODUCTION

1. GENERAL 5-1-1

PREPARATION FOR DISASSEMBLY

2. INSTALLATION OF ENGINE IN OVERHAUL STAND 5-1-1

3. DRAINING ENGINE OIL 5-1-1

A. Drain oil from engine : 5-1-1

ENGINE - EXTERNALS

4. IGNITION CURRENT REGULATOR, GLOW PLUG CABLES ANDGLOW PLUGS (Pre-SB1429) 5-1-4

A. Remove ignition current regulator, glow plug cables and glowplugs, : 5-1-4

5. IGNITION EXCITER, IGNITION CABLES AND SPARK IGNITERS(Post-SB1429) 5-1-4

A. Remove Ignition Cables and Spark Igniters : 5-1-4

B. Remove Ignition Exciter and Bracket 5-1-5

6. PRESSURE OIL TRANSFER TUBES 5-1-5

A. Remove pressure oil transfer tubes : 5-1-5

7. SCAVENGE OIL TRANSFER TUBES 5-1-7

A. Remove scavenge oil transfer tubes : 5-1-7

8. NO. 2 BEARING SCAVENGE OIL TUBE 5-1-9

A. Remove No. 2 bearing scavenge oil tube assembly : 5-1-9

9. FUEL TUBES 5-1-10

A. Remove fuel tubes : 5-1-10

10. PROPELLER REVERSING INTERCONNECT LINKAGE -(PT6A-20, -20A AND -20B ENGINES) 5-1-10

A. Disassemble propeller reversing interconnect linkage : 5-1-10

TABLE OF CONTENTSSUBJECT PAGE



Page 1PART 5 CONTENTS Jul 01/2005

(Cont’d)

11. TEMPERATURE COMPENSATOR AND AIR PRESSURE TUBES(Pre-SB1294) 5-1-23

A. Remove temperature compensator and air pressure tubes : 5-1-23

12. TEMPERATURE COMPENSATOR, ASSOCIATED AIR PRESSURETUBES AND P3 FILTER ASSEMBLY (Post-SB1294) 5-1-24

A. Remove temperature compensator, associated tubes and P3filter assembly : 5-1-24

13. FUEL CONTROL UNIT (FCU) AND FUEL PUMP 5-1-29

A. Remove FCU and fuel pump : 5-1-29

14. OIL-TO-FUEL HEATER, CHECK VALVE AND ASSOCIATEDTUBES 5-1-32

A. Remove oil-to-fuel heater, check valve and associated tubes : 5-1-32

15. AIR INLET SCREEN AND INLET FAIRING 5-1-32

A. Remove air inlet screen and inlet fairing : 5-1-32

16. CENTER AND REAR FIRESEALS 5-1-33

A. Remove center and rear fireseals as follows: 5-1-33

17. COMPRESSOR BLEED VALVE 5-1-33

A. Remove compressor bleed valve as follows: 5-1-33

18. DIPSTICK AND OIL FILLER TUBE 5-1-33

A. Remove dipstick and oil filler tube as follows: 5-1-33

ENGINE - GENERAL

19. OIL FILTER ELEMENT, HOUSING AND CHECK VALVE(Pre-SB1247) 5-1-35

A. Remove oil filter element, housing and check valve : 5-1-35

20. OIL FILTER ELEMENT, HOUSING AND CHECK VALVE(Post-SB1247) 5-1-35

A. Remove oil filter element, housing and check valve : 5-1-35





(Cont’d)

21. OIL PRESSURE RELIEF VALVE 5-1-39

A. Remove oil pressure relief valve : 5-1-39

22. EXTERNAL SCAVENGE PUMP - WITHOUT VACUUM PUMPDRIVE 5-1-39

A. Remove external scavenge oil pump from accessory gearboxhousing : 5-1-39

23. EXTERNAL SCAVENGE OIL PUMP - WITH VACUUM PUMPDRIVE 5-1-41

A. Remove external scavenge oil pump from accessory gearboxhousing : 5-1-41

24. ACCESSORY GEARBOX (Post-SB1045, Pre-SB1104,Post-SB1134 AND PT6A-20A ENGINES) 5-1-44

A. Remove and split accessory gearbox : 5-1-44

25. ACCESSORY GEARBOX (Post-SB1104 AND Pre-SB1134) 5-1-45

A. Remove and split accessory gearbox : 5-1-45

26. INTERNAL SCAVENGE PUMP AND OIL TRAY 5-1-49

A. Remove internal scavenge pump and (Post-SB1122) oil trayfrom rear housing : 5-1-49

27. ACCESSORY DRIVE BEARINGS 5-1-49

A. Remove accessory drive bearings : 5-1-49

28. ACCESSORY DRIVE SEALS 5-1-51

A. Remove accessory gearbox drive seals as follows: 5-1-51

29. PRESSURE OIL PUMP 5-1-53

A. Remove pressure oil pump from front face of accessorygearbox diaphragm as follows: 5-1-53

30. POWER SECTION 5-1-53

A. Remove power section from gas generator case as follows: 5-1-53





(Cont’d)

31. FUEL MANIFOLD AND FUEL DUMP VALVE 5-1-53

A. Remove fuel manifold and fuel dump valve : 5-1-53

32. COMBUSTION CHAMBER LINER AND GAS GENERATOR CASEDRAIN VALVES 5-1-55

A. Remove combustion chamber liner and gas generator casedrain valves : 5-1-55

33. COMPRESSOR TURBINE SINGLE PLANE BALANCINGASSEMBLY (Pre-SB1043 Engines) 5-1-57

A. Remove turbine disk assembly : 5-1-57

34. COMPRESSOR TURBINE TWO PLANE BALANCING ASSEMBLY(Post-SB1043 AND PT6A-20A Engines) 5-1-59

A. Remove compressor turbine assembly : 5-1-59

35. COMPRESSOR TURBINE VANES, SHROUD SEGMENTS,SHROUD HOUSING AND SMALL (INNER) EXIT DUCT 5-1-59

A. Remove compressor turbine vanes, shrouds, shroud housingand small (inner) exit duct assembly : 5-1-59

36. COMPRESSOR TURBINE BLADES 5-1-61

A. Remove blades from compressor turbine assembly : 5-1-61

37. COMBUSTION CHAMBER LARGE (OUTER) EXIT DUCT 5-1-68

A. Remove combustion chamber large (outer) exit duct : 5-1-68

38. COMPRESSOR INLET CASE 5-1-68

A. Remove compressor inlet case as follows: 5-1-68

39. NO. 1 BEARING 5-1-69

A. Remove No. 1 bearing from gas generator case : 5-1-69

40. COMPRESSOR ROTOR (Pre-SB1094) 5-1-71

A. Remove compressor rotor assembly from gas generator caseas follows: 5-1-71

B. Disassemble compressor rotor assembly as follows: 5-1-71





(Cont’d)

41. COMPRESSOR ROTOR (Post-SB1094 AND PT6A-20A ENGINESENGINES) 5-1-75

A. Remove compressor rotor assembly from gas generator caseas follows: 5-1-75

B. Disassemble compressor rotor assembly : 5-1-78

42. NO. 2 BEARING FRONT STATOR AIR SEAL AND GASGENERATOR CASE 5-1-79

A. Remove No. 2 bearing front stator air seal and gas generatorcase as follows: 5-1-79

43. T5 THERMOCOUPLE HARNESS ASSEMBLY (Pre-SB1073 WITHPost-SB1246) 5-1-81

A. Remove T5 thermocouple harness assembly : 5-1-81

44. T5 THERMOCOUPLE HARNESS, BUS-BAR AND PROBES(Post-SB1073 AND ALL PT6A-20A ENGINES) WITHPost-SB1246 5-1-83

A. Remove thermocouple harness, bus-bar assembly and probes: 5-1-83

45. POWER TURBINE INTERSTAGE BAFFLE AND VANES(Pre-SB1061) 5-1-86

A. Remove power turbine interstage baffle and power turbinevanes : 5-1-86

46. TURBINE INTERSTAGE STATOR HOUSING AND POWERTURBINE VANE RING (Post-SB1061 AND PT6A-20A ENGINES) 5-1-86

A. Remove turbine interstage stator housing and power turbinevane ring from power section : 5-1-86

47. POWER TURBINE ASSEMBLY AND SHROUD (Pre-SB1046) 5-1-87

A. Remove power turbine assembly and shroud : 5-1-87

48. POWER TURBINE ASSEMBLY AND SHROUD RING(Post-SB1046 AND PT6A-20A ENGINES) 5-1-87

A. Remove power turbine disk and blade assembly as follows : 5-1-87





(Cont’d)

49. POWER TURBINE BLADES 5-1-87

A. Remove blades from power turbine assembly : 5-1-87

B. Remove balance weights, retaining rivets and balance rivets : 5-1-93

50. REDUCTION GEARBOX 5-1-95

A. Remove reduction gearbox from exhaust duct : 5-1-95

51. POWER TURBINE SHAFT AND SHAFT HOUSING (Pre-SB1046) 5-1-97

A. Remove and Disassemble Power Turbine Shaft and ShaftHousing : 5-1-97

52. POWER TURBINE SHAFT AND SHAFT HOUSING (Post-SB1046and Pre-SB1057) 5-1-99

A. Remove and disassemble power turbine shaft and shafthousing : 5-1-99

53. POWER TURBINE SHAFT HOUSING (Post-SB1057 ANDPre-SB1089 ENGINES) 5-1-105

A. Remove and disassemble power turbine shaft housing : 5-1-105

54. POWER TURBINE SHAFT HOUSING (Post-SB1089 andPT6A-20A ENGINES) 5-1-105

A. Remove and disassemble power turbine shaft housing : 5-1-105

55. POWER TURBINE SHAFT 5-1-108

A. Disassemble power turbine shaft : 5-1-108

56. REDUCTION GEARBOX REAR CASE 5-1-108

A. Disassemble reduction gearbox rear case : 5-1-108

57. FIRST STAGE REDUCTION PLANET GEAR CARRIER(Pre-SB1124) 5-1-109

A. Disassemble first-stage reduction planet gear carrier : 5-1-109

58. FIRST STAGE REDUCTION PLANET GEAR CARRIER(Post-SB1124 and PT6A-20A Engines) 5-1-109

A. Disassemble first-stage reduction planet gear carrier : 5-1-109





(Cont’d)

59. REDUCTION GEARBOX FRONT CASE (Pre-SB1124) 5-1-112

A. With front case of reduction gearbox mounted on Base(PWC30322), disassemble front case : 5-1-112

60. REDUCTION GEARBOX FRONT CASE (Post-SB1124 ANDPT6A-20A ENGINES) 5-1-113

A. With reduction gearbox front case mounted on Base(PWC30322) disassemble front case : 5-1-113

61. PROPELLER SHAFT 5-1-121

A. Disassemble propeller shaft : 5-1-121

62. PROPELLER SHAFT OIL TRANSFER TUBE (Pre-SB1124) 5-1-122

A. Disassemble propeller shaft oil transfer tube assembly : 5-1-122

63. PROPELLER SHAFT OIL TRANSFER TUBE (Post-SB1124 ANDPT6A-20A ENGINES) 5-1-122

A. Disassemble propeller shaft oil transfer tube assembly : 5-1-122

64. FRONT ACCESSORY DRIVES 5-1-122

A. Remove accessory drives from reduction gearbox front case : 5-1-122

65. SECOND-STAGE REDUCTION PLANET GEAR CARRIER ANDOIL NOZZLES 5-1-123

A. With planet gear carrier installed on Holding Fixture(PWC30131), disassemble planet gear carrier and remove oilnozzles as follows: 5-1-123




Page 7/8PART 5 CONTENTS Jul 01/2005

Engine - Externals Figure 5-1-1 5-1-2

Ignition Cables Figure 5-1-2 5-1-6

Ignition Exciter Installation Figure 5-1-3 5-1-8

Fuel Control unit, Fuel Pump, Temperature Compensator, Fuel Pressure and Airpressure Tubes Figure 5-1-4 5-1-12

Engine Rear Linkage Figure 5-1-5 5-1-14

Propeller Reversing Interconnect Linkage Figure 5-1-6 5-1-16

Propeller Reversing Interconnect Linkage Figure 5-1-7 (Sheet 1 of 2) 5-1-18

Propeller Reversing Interconnect Linkage Figure 5-1-7 (Sheet 2) 5-1-19

Temperature Compensator, Air Pressure Tubes and P3 Air Filter Figure 5-1-8 5-1-26

Heated Line Wiring Detail (Typical) Figure 5-1-9 5-1-28

Oil-to-Fuel Heater, Oil Pressure Relief Valve, Check Valve and Tubing Figure5-1-10 5-1-30

Compressor Inlet Area - Inlet Screen Removed Figure 5-1-11 5-1-34

Oil Filter, Housing and Check Valve Figure 5-1-12 5-1-36

Removal of Oil Filter Housing and Check Valve Figure 5-1-13 5-1-38

Oil Filter, Housing and Check Valve - Exploded View Figure 5-1-14 5-1-40

External Scavenge Oil Pump Figure 5-1-15 5-1-42

Removal of Accessory Gearbox Figure 5-1-16 5-1-46

Disassembly of Accessory Gearbox Figure 5-1-17 5-1-48

Recommended Record Sheet for Drive Bearings Figure 5-1-18 5-1-50

Impeller and Starter Gearshaft - Disassembly Figure 5-1-19 5-1-52

Fuel Manifold and Dump Valve Figure 5-1-20 5-1-54

Combustion Chamber Liner Figure 5-1-21 5-1-56

Compressor Turbine Assembly Figure 5-1-22 5-1-58

Compressor Turbine Assembly Figure 5-1-23 5-1-60

LIST OF FIGURESFIGURE PAGE



Page 1PART 5 LIST OF FIGURES Jul 01/2005

Compressor Turbine Vanes, Shroud Segments, Shroud Housing and Exit DuctsFigure 5-1-24 5-1-62

Compressor Turbine Blade Removal Figure 5-1-25 (Sheet 1 of 2) 5-1-64

Compressor Turbine Blade Removal Figure 5-1-25 (Sheet 2) 5-1-65

No. 1 Bearing Removal Figure 5-1-26 5-1-70

Compressor Tie Rod Removal Figure 5-1-27 5-1-72

Compressor Rear Hub Removal Figure 5-1-28 5-1-74

Compressor Rotor Assembly Figure 5-1-29 5-1-76

Compressor Rotor Assembly Figure 5-1-30 5-1-80

T5 Thermocouple Harness and Probes Figure 5-1-31 5-1-82

T5 Thermocouple Harness, Busbar and Probes Figure 5-1-32 5-1-84

Power Turbine Vanes, Shroud and Exhaust Duct Figure 5-1-33 5-1-88

Power Turbine Assembly Figure 5-1-34 5-1-90

Power Turbine Assembly Figure 5-1-35 5-1-92

Power Turbine Blades Removal Figure 5-1-36 5-1-94

Reduction Gearbox Front Case Figure 5-1-37 5-1-96

Removal of Rear Case of Reduction Gearbox from Exhaust Duct Figure 5-1-38 5-1-98

Power Turbine Shaft and Shaft Housing Figure 5-1-39 5-1-100

Power Turbine Shaft and Shaft Housing Figure 5-1-40 5-1-102

Power Turbine Shaft Housing Figure 5-1-41 5-1-106

Reduction Gearbox Rear Housing Components Figure 5-1-42 5-1-110

Propeller Shaft and Bevel Gear Shafts Figure 5-1-43 5-1-114

Second-stage Planet Gear Carrier Figure 5-1-44 5-1-116

Reduction Gearbox Front Housing Externals Figure 5-1-45 5-1-118

LIST OF FIGURESFIGURE PAGE



Page 2PART 5 LIST OF FIGURES Jul 01/2005

LIST OF TABLES

TITLE PAGE

NO TABLES IN THIS SECTION



Page 1/2PART 5 LIST OF TABLES Jul 01/2005

PART 5 - DISASSEMBLY

INTRODUCTION

1. GENERAL

A. It is recommended that the engine be disassembled in the sequence given in this part.As each subassembly or component is removed, it should be transferred to a parts rackto ensure protection against damage during storage. Individual parts removed fromreduction gearbox must be segregated and identified to ensure reassembly in originalpositions. Subassemblies should be covered, and all projecting parts, such as shafts,gears, bushings and studs, supported and protected. All openings should be coveredwith suitable plastic plugs or covers. Care should be taken to avoid bending tubing.Removal instructions are not included for the following accessories which, it isassumed, have been removed from the engine prior to commencement of overhaul:Starter generator; Nf tachometer-generator; propeller constant speed unit; Ngtachometer-generator; propeller overspeed governor; and power turbine governor.

B. All parts should be examined for evidence of scoring, burning or other damage. Specialnote should be taken of any damage which might not be apparent after cleaning.Affected parts should be tagged and laid out for detailed inspection prior to cleaning.The use of disassembly history sheets, to be later included in engine records, isrecommended.

C. Hot section nuts and bolts should be segregated, and care should be taken to preventparts becoming mixed. Design improvements may necessitate material substitution inoverhauled engines, resulting in unnecessary extensive sorting if parts have beenindiscriminately mixed.

D. Bearings should be handled with special care. Use of clean cotton or synthetic rubbergloves is necessary to prevent bare-handed contact with bearing surfaces. Perspirationcan cause corrosion despite the light film of oil that normally protects bearings.Excess oil may be removed with a clean, lint-free cloth. Bearings to be stored should becoated with a light film of lubricating oil, wrapped in clean, grease-proof paper andplaced in individual, closed containers.

E. Special disassembly tools and fixtures are listed in Part 4.

PREPARATION FOR DISASSEMBLY

2. INSTALLATION OF ENGINE IN OVERHAUL STAND

A. For installation of engine in overhaul stand, refer to Part 13.

3. DRAINING ENGINE OIL

A. Drain oil from engine (See Fig. 5-1-1):

(1) Place drip pan under overhaul stand, ensuring that engine is in horizontal position.



Page 5-1-1Jul 01/2005

1

2

3

4

5

6

7

8

9

10

11

12

19 18 17 16 15 14 13

30

29

31

27

28

26

24

25

23

22

21

20

C41507A

Engine - ExternalsFigure 5-1-1



Page 5-1-2May 23/2003

Key to Figure 5-1-1

1. Rear Scavenge Oil Tube Assembly2. Retaining Plate3. Plug4. Flange G5. Oil Tank Drain Plug6. Cotterpin and Lockpin7. Tube-to-Boss Rear Elbow8. Sealing Sleeve9. Rear Transfer Tee - Sleeve

10. Oil Transfer Tee - Pressure11. Centre Transfer Tube - Pressure12. Glow Plugs (Pre-SB1429); Spark Igniters (Post-SB1429)13. Tube Coupling - Pressure14. Front Transfer Tube - Pressure15. Front Elbow - Scavenge16. Plug (Pre-SB1217); Chip Detector (Post-SB1217)17. Front Elbow - Scavenge18. Front Transfer Tubes - Scavenge19. Scavenge Tube Coupling - Front20. Center Transfer Tubes - Scavenge21. Scavenge Tube Coupling - Rear22. No. 3 and 4 Bearing Transfer Tube - Scavenge23. Reduction Gearbox Transfer Tube - Scavenge24. No. 2 Bearing Transfer Tube - Scavenge25. Transfer Tubes26. Rear Elbow - Scavenge27. External Scavenge Pump28. Output Receptacles29. Scavenge Oil Rear Tee30. Ignition Regulator Cover (Pre-SB1429)31. Ignition Current Regulator (Pre-SB1429); Ignition Exciter

(Post-SB1429)



Page 5-1-3May 23/2003

(2) Remove oil drain plug cotterpin and lockpin (6) from bottom of compressor inletcase and remove drain plug (5) using Puller (PWC30077).

(3) Remove oil drain plug (3) located at 6 o’clock position on accessory gearboxhousing.

(4) Pre-SB1217: Remove oil drain plug (16) located at 6 o’clock position on reductiongearbox front case.

(5) Post-SB1217: Remove chip detector cover and chip detector (16) located at6 o’clock position on reduction gearbox front case.

ENGINE - EXTERNALS

4. IGNITION CURRENT REGULATOR, GLOW PLUG CABLES AND GLOW PLUGS(Pre-SB1429)

A. Remove ignition current regulator, glow plug cables and glow plugs, (See Fig. 5-1-1):

(1) Disconnect ignition cables from output receptacles (28) at ignition current regulatorcover (30).

(2) Remove three bolts and washers securing ignition current regulator (31) toaccessory gearbox housing and remove regulator and slotted spacer.

(3) Disconnect cables at glow plugs (12).

(4) Detach all cable support clamps and retaining plates on fireseals.

(5) Remove cables by pulling them rearward through center fireseal and forwardthrough rear fireseal.

(6) Remove two glow plugs and gaskets from gas generator case.

5. IGNITION EXCITER, IGNITION CABLES AND SPARK IGNITERS (Post-SB1429)

A. Remove Ignition Cables and Spark Igniters (Ref. Fig. 5-1-2):

(1) Isolate power from ignition system.

CAUTION: WHEN UNSCREWING COUPLING NUTS, DO NOT ALLOW BRAIDING,FERRULES OR IGNITER TO TURN AT SAME TIME.

(2) Disconnect coupling nuts on left and right ignition cables (7) and (8) from respectivespark igniters (1) and ignition exciter (9).

(3) Remove self-locking nuts and bolts securing loop clamps (3 and 5) to anglebrackets (4 and 2) on center fireseal angle brackets and gas generator case integralbrackets (Ref. Detail A).

(4) Remove self-locking nuts and bolts securing loop clamps (10 and 12) to brackets(11 and 13) (Ref. Detail C).



Page 5-1-4May 23/2003

(5) Remove self-locking nuts and bolts securing loop clamp (21) to angle bracket (20)(Ref. Detail D).

(6) Remove self-locking nuts and bolts securing loop clamp (19) to loop clamp on fuelline (Ref. Detail D).

(7) Remove self-locking nuts and bolts securing loop clamps (14) to angle brackets(22) (Ref. Detail D).

(8) Remove self-locking nuts and bolts and separate loop clamps (15 and 17), andbrackets (16 and 18) from rear fireseal mount ring (Ref. Detail D).

(9) Remove self-locking nuts and bolts and separate loop clamps (6) from ignitioncables (7 and 8) (Ref. Detail B).

(10) Withdraw ignition cables (7 and 8) through fireseal mount rings.

(11) Remove two spark igniters (1) and gaskets from gas generator case.

(12) Overhaul removed parts (Ref. PART 16).

B. Remove Ignition Exciter and Bracket (Ref. Fig. 5-1-3)

(1) Support ignition exciter (3) and remove self-locking nuts (5), washers (4) from bolts(1). Remove ignition exciter from mounting bracket (2).

(2) Support mounting bracket (2) and remove three bolts (6) and washers (7).

(3) Remove mounting bracket from accessory gearbox.

(4) Overhaul removed parts (Ref. Part 16).

6. PRESSURE OIL TRANSFER TUBES

A. Remove pressure oil transfer tubes (See Fig. 5-1-1):

(1) Remove bolts and washers securing front elbow (15) to front case of reductiongearbox.

(2) Remove bolts securing tube coupling (13) to flange C.

(3) Withdraw elbow (15), together with front transfer tube (14), from front case.

(4) Remove tube coupling (13) and center transfer tube (11).

(5) Remove bolts securing oil transfer tee (10) to gas generator case. Remove tee andinternal oil transfer tube.

(6) Detach retaining plates and seals at center and rear fireseals.

(7) Remove rear transfer tube (9).



Page 5-1-5May 23/2003

DETAIL A DETAIL B

DETAIL CDETAIL D

1

2

5 4

3

7

8

6

AB

17

9

18

C

D

1

11

10

12

13

1516

14

1918

17

21

20

22

C7993A

Ignition CablesFigure 5-1-2

Post SB1429



Page 5-1-6May 23/2003

(8) Remove bolts and washers securing tube-to-boss rear elbow (7) to compressor inletcase. Remove elbow.

(9) Remove preformed packings from transfer tubes.

(10) Remove self-locking nuts and bolts securing sealing sleeve (8) to rear fireseal.Remove sleeve.

7. SCAVENGE OIL TRANSFER TUBES

A. Remove scavenge oil transfer tubes (See Fig. 5-1-1):

(1) Remove bolts and washers securing front elbow (17) to front case of reductiongearbox.

(2) Remove elbow (17), sealing sleeve and front transfer tubes (18) from coupling (19).

(3) Remove self-locking nuts, washers and bolts securing coupling (19) to flange Cand remove coupling.

(4) Detach retaining plates and seals from center fireseal. Remove center transfertubes (20) from coupling (21).

Key to Figure 5-1-2

1. Spark Igniter2. Angle Bracket3. Loop Clamp4. Angle Bracket5. Loop Clamp6. Loop Clamp7. Ignition Cable (L.H.)8. Ignition Cable (R.H.)9. Igniter Exciter

10. Loop Clamp11. Angle Bracket12. Loop Clamp13. Angle Bracket14. Loop Clamp15. Loop Clamp16. Angle Bracket17. Loop Clamp18. Angle Bracket19. Loop Clamp20. Angle Bracket21. Loop Clamp22. Angle Bracket



Page 5-1-7May 23/2003

ACCESSORY GEARBOX(REF.)

1

2

3

76 4

5

C87257

Ignition Exciter InstallationFigure 5-1-3

Post SB1429



Page 5-1-8May 23/2003

(5) Remove bolts securing No. 2 bearing transfer tube (24) to coupling (21).

(6) Detach retaining plates and seals securing No. 3 and No. 4 bearing transfer tube(22) and reduction gearbox transfer tube (23) to rear fireseal.

(7) Remove bolts and washers securing coupling (21) to gas generator case.

(8) Remove coupling, together with transfer tubes (22) and (23), forward through rearfireseal.

(9) Remove retaining rings from transfer tubes (25) and remove tubes from rear elbow(26) and external scavenge pump (27).

(10) Remove self-locking nuts securing rear elbow (26) to flange G (4). Remove elbow.

(11) Remove preformed packings and packing retainers (if fitted) from transfer tubes.

(12) Remove bolts securing rear tee (29) to external scavenge pump (27).

(13) Remove bolts securing retaining plate (2) and scavenge oil rear tube (1) toaccessory gearbox boss. Remove rear tube, plate and tee and remove preformedpackings from tube and plate.

8. NO. 2 BEARING SCAVENGE OIL TUBE

A. Remove No. 2 bearing scavenge oil tube assembly (See Fig. 5-1-1):

(1) Detach retaining plates and seals at rear fireseal.

(2) Remove bolts securing rear flange of tube assembly (24) to compressor inlet case.

(3) Withdraw tube assembly through rear fireseal.

(4) Withdraw short, internal transfer tube from compressor inlet case using Puller(PWC30128-04).

(5) Remove preformed packings from transfer tubes.

Key to Figure 5-1-3

1. Bolt2. Mounting Bracket3. Ignition Exciter4. Washer5. Nut6. Bolt7. Washer



Page 5-1-9May 23/2003

9. FUEL TUBES

A. Remove fuel tubes (See Fig. 5-1-4):

(1) Disconnect coupling nuts of fuel pressure tube (18) at fuel control unit (1) andcoupling at rear fireseal (10). Remove tube.

(2) Disconnect coupling nuts of fuel pressure tube (35) from center tube (30) at centerfireseal (29), and from dump valve. Remove tube.

(3) Remove locknuts (15) and plain washers (28) securing fuel pressure tube (30) torear and center fireseals.

(4) Remove bolt and self-locking nut at loop clamp (31), and remove tube (30).

10. PROPELLER REVERSING INTERCONNECT LINKAGE - (PT6A-20, -20A AND -20BENGINES)

A. Disassemble propeller reversing interconnect linkage (See Fig. 5-1-5, 5-1-6 and 5-1-7):

NOTE: Before removing interconnect linkage, note respective locations of spacers,bushings and clamps. Note bolt and pin orientation.

CAUTION: AS A GENERAL PRACTICE, DO NOT INTERMINGLE REVERSINGLINKAGE PARTS OF A PT6A-20 WITH A PT6A-20A or B. THEY ARE NOTNECESSARILY THE SAME PART NUMBERS. IF IN DOUBT, REFERTO ILLUSTRATED PARTS CATALOG.

(1) Remove propeller reversing rear linkage as follows:

(a) Remove FCU interconnect rod (6, Fig. 5-1-5) from actuating lever (2) and FCUcontrol arm (9) by removing two cotterpins, castellated nuts, washers and bolts.

(b) Disconnect rear clevis rod end (3) from propeller control cam (1) by removingcotterpin, washer and straight pin.

(c) Loosen self-locking nut on clamp bolt (2, Fig. 5-1-6) and remove rear wirerope terminal by unscrewing from wire rope.

(d) Remove mounting bracket (8, Fig. 5-1-5) complete with rear linkage fromflange G, by removing two self-locking nuts and one bolt.

(e) Disassemble rear linkage from mounting bracket as follows:

1 Remove extension spring (5) from actuating lever (2) and mounting bracketby removing two cotterpins and washers.

2 Remove two cotterpins, washers, straight pin (17) cam follower pin (16),and remove control cam (1) and actuating lever (2) from mountingbracket (8).

3 Loosen lock bolt on cam follower lever (15). Remove splined, grooved pin(7) follower lever (15) and actuating lever (13) from mounting bracket (8).



Page 5-1-10May 23/2003

(2) Remove propeller reversing front linkage (PT6A-20 engines) as follows: (See Fig.5-1-6).

(a) Disconnect rear rod end clevis (1) from propeller control lever (8) by removingcotterpin, washer and shackle pin (6).

(b) Slacken nut on clamping bolt (2) and unscrew rear wire rope terminal (3) fromend of wire rope (26). Slacken locknut and remove rear rod end clevis (1) andlocknut from terminal (3).

NOTE: Wire rope thread is left handed.

(c) Remove control lever mounting bracket (32) with linkage from flange G, byremoving two nuts and bolts at flange, and single bolt at angle bracket.

(d) Remove cotterpin and washer securing shoulder pin (cam follower) (30).Withdraw shoulder pin securing propeller follower lever (9) to propeller controllever (8).

(e) Unscrew bolt securing follower lever (9) to grooved pin. Withdraw grooved pinto remove follower lever and FCU actuating lever (5) from mounting bracket(32).

(f) Remove cotterpins and washers from studs on mounting bracket (32) and FCUactuating lever (7), and remove spring (10).

(g) Remove cotterpin, washer and straight pin securing propeller control lever (8)and actuating lever (7) to mounting bracket (32).

(h) Remove cotterpins (45), nuts (46), washers (49), connecting front rod endclevis (43) and propeller interconnecting rod (16) to propeller reversinglever (17) and spacer sleeve (47).

(i) Disconnect propeller reversing lever interconnecting rod (16) from powerturbine governor lever (21) by removing cotterpin (45), nut (46), washers (49) andbolt (56).

(j) Unscrew front wire rope case (23) nut and locknut (22) from front swivel joint(35).

(k) Withdraw front swivel joint (35), complete with wire rope (26) and attachedlinkage, from engine lifting bracket (13). Post-SB1185; remove two nuts andbolts (13C) and retaining plate (13B) from bracket (13A).

(l) Disassemble front linkage as follows: (See Fig. 5-1-6 Detail B).

1 Remove self-locking nut and washer (44) from clamping bolt (37).

2 Unscrew wire rope (26) from terminal and front swivel joint (35) and terminal(15).

NOTE: Wire rope is left-hand threaded.



Page 5-1-11May 23/2003

3233

34

28 1535

30 29

31

19 20 2122

23 24

18

17

1 23

4 5 6 7

8

9

16

15 14 1312 11

10

25 26 2715

28

C1597A

Fuel Control unit, Fuel Pump, Temperature Compensator, Fuel Pressure and Air pressure TubesFigure 5-1-4



Page 5-1-12May 23/2003

Key to Figure 5-1-4

1. Fuel Control Unit2. Self-locking Nut and Washer3. Coupling4. Fuel Pump5. Nut6. Washer7. Gasket8. Preformed Packing9. Straight Nipple

10. Rear Fireseal11. Temperature Compensator12. Preformed Packing13. Hexagon Plug14. Bulkhead Coupling15. Locknut16. Hose Assembly17. Elbow, Nut and Preformed Packings18. Fuel Pressure Tube - Rear19. Preformed Packing20. Straight Nipple21. Air Pressure Tube Assembly22. Enrichment Air Pressure Tube23. Screw and Washer24. Air Pressure Tube - Front25. Temperature Compensator Bracket26. Electrical Receptacle27. Self-locking Nut and Washer28. Washer29. Center Fireseal30. Fuel Pressure Tube - Center31. Loop Clamp32. Gasket33. Flanged Elbow34. Double-hexagon Bolt35. Fuel Pressure Tube - Front



Page 5-1-13May 23/2003

1 2 3 4

15

16

17

5

6

7

8

910

11

14

13 12

C1969

Engine Rear LinkageFigure 5-1-5

PT6A-20, -20A and -20B Engines



Page 5-1-14May 23/2003

3 Unlock nut (42) and remove front rod end clevis (43) from terminal (15).

4 Slacken locknut (41) and unscrew low pitch adjuster stop (40) from low pitchstop adjuster (39). Remove adjuster stop (40), wire rope terminal (15) andcompression spring (36).

5 Remove lockbolt (38) securing low pitch stop adjuster (39) to front swiveljoint (35). Unscrew stop adjuster from swivel joint.

(m) Remove nuts and bolts securing two clamps around front wire rope casing, tobracket and governor air pressure tube, and remove clamps.

(n) Disconnect front wire rope casing (23) from cable coupling (24) and removecasing.

(o) Disconnect rear wire rope casing (27) from cable coupling (24), and rear swiveljoint (28), and remove casing.

(p) Remove nut and washer securing cable coupling (24) to center fireseal (25),and remove cable coupling and washer.

(q) Remove nut and washer securing rear swivel joint (28) to rear fireseal (29),and remove swivel joint.

(r) Remove self-locking nuts (55) and washers (49) securing propeller governorarms (54) to propeller governor (14).

Key to Figure 5-1-5

1. Propeller Control Cam2. Fuel Control Actuating Lever (6, Fig. 5-1-7)3. Clevis Rod End (2. Fig. 5-1-7)4. Locknut (3, Fig. 5-1-7)5. Extension Spring (36, Fig. 5-1-7)6. FCU Control Rod (41, Fig. 5-1-7)7. Grooved Pin (38, Fig. 5-1-7)8. Mounting Bracket9. FCU Control Arm (44, Fig. 5-1-7)

10. FCU Arm Extension (43, Fig. 5-1-7)11. Serrated Spacer (49, Fig. 5-1-7)12. Angle Bracket13. Actuating Lever (40, Fig. 5-1-7)14. Idle Deadband Adjusting Bolt (NON-STOL APPLICATION)

(5, Fig. 5-1-7)15. Cam Follower Lever (51, Fig. 5-1-7)16. Cam Follower Pin (37, Fig. 5-1-7)17. Straight Headed Pin



Page 5-1-15May 23/2003

C1598A

Propeller Reversing Interconnect LinkageFigure 5-1-6

PT6A-20 Engines



Page 5-1-16May 23/2003

Key to Figure 5-1-6

1. Rear Rod End Clevis2. Wire Rope Clamp Bolt3. Wire Rope Terminal4. Idle Deadband Adjustment5. FCU Actuating Lever6. Cotterpin, Washer and Shackle

Pin7. FCU Actuating Lever8. Propeller Control Lever9. Propeller Follower Lever

10. Extension Spring11. Fuel Control Unit (Reference)12. Beta Control Cylinder and Spring

Step13. Engine Front Lifting Bracket

(Pre-SB1185)13A. Engine Front Lifting Bracket

(Post-SB1185)13B. Retaining Plate13C. Bolt

14. Propeller Governor (Reference)15. Front Wire Rope Terminal16. Propeller Reversing Lever

Interconnecting Rod17. Propeller Reversing Lever18. Power Turbine Governor

(Reference)19. Power Turbine Governor Arm20. Power Turbine Governor

Interconnecting Rod21. Power Turbine Governor Lever22. Nut23. Front Wire Rope Casing24. Cable Coupling25. Center Fireseal26. Wire Rope27. Rear Wire Rope Casing28. Rear Swivel Joint

29. Rear Fireseal30. Shoulder Pin31. Power Control Lever (Reference)32. Control Lever Mounting Bracket33. FCU Control Rod34. FCU Control Arm35. Front Swivel Joint36. Compression Spring37. Wire Rope Clamp Bolt38. Bolt39. Low Pitch Stop Adjuster40. Low Pitch Adjuster Stop41. Nut42. Nut43. Front Rod End Clevis44. Self-locking Nut and Washer45. Cotterpin46. Castellated Nut47. Spacer Sleeve48. Shouldered Stud49. Plain Washer50. Bolt51. Plain Bearing52. Retaining Ring53. Bushing Sleeve54. Propeller Governor Arm55. Self-locking Nut56. Bolt57. Shoulder Bolt58. Propeller Governor Actuating

Lever59. Propeller Reversing Lever

Guidepin60. Power Turbine Governor Lever

Bracket61. Plain Bearing



Page 5-1-17May 23/2003

DETAIL A

8

26

POST−SB1185

LOW PITCH & REVERSE

HIGH PITCH & FEATHER

PROPELLER FEEDBACK RING13

AC

21

14

16

1112

TO COCKPIT PROPELLERCONTROL LEVER

CENTER FIRESEAL

10

7

8 9

B

35

733

32

17

18

3447

48

51 1

50 2

6

REAR FIRESEAL

46 45

44 43

42

41

49

4037

39

38

36

TO COCKPIT POWERCONTROL LEVER

C1967C_1

Propeller Reversing Interconnect LinkageFigure 5-1-7 (Sheet 1 of 2)

PT6A-20A and -20B Engines



Page 5-1-18May 23/2003

DETAIL B

DETAIL C

DETAIL C

REVERSE POSITIONTAKE−OFF POSITION

CAM TRACK POINT

IDLE POSITION

61 2

3 4

590 1° °±

30

29

2728

25 14 122423212220

1915

MAX. STOP

CARBONBLOCK(REF.)

PT6A−20A PUSH−PULL CONTROLROD ARRANGEMENT (SOLID LINK)

14

31

CARBONBLOCK(REF.)

LOCK BOLT

GOVERNOR AIRBLEED LINK

30

29

54

28

53

12

1425275224232221

MAX. STOP

19 15

31

14

PT6A−20B PUSH−PULL CONTROLROD ARRANGEMENT (TELESCOPIC LINK)

21

C1967C_2

Propeller Reversing Interconnect LinkageFigure 5-1-7 (Sheet 2)

PT6A-20A and -20B Engines



Page 5-1-19May 23/2003

Key to Figure 5-1-7

1. Propeller Control Cam2. Clevis Rod End3. Locknut4. Clamp Bolt5. Idle Deadband Adjustment

(NON-STOL APPLICATION)6. FCU Actuating Lever7. Coupling Nut8. Front Lifting Bracket9. Setting Maximum Stop

10. Propeller Governor11. Propeller Speed Adjusting Lever12. Clevis Rod End13. Propeller Feedback Ring14. Propeller Governor Interconnect-

ing Rod15. Lock Bolt16. Bracket17. Insulation Bracket18. Self-locking Nut19. Front Swivel Joint20. Locknut21. Low Pitch Adjuster Stop22. Spring23. Locknut24. Low Pitch Adjuster Stop25. Castellated Nut26. Retaining Plate27. Clamp Bolt

28. Self-locking Nut29. Propeller Reversing Lever30. Beta Valve Clevis31. Governor Air Bleed Link32. Wire Rope33. Wire Rope Casing34. Locknuts35. Rear Swivel Joint36. Extension Spring37. Cam Follower Pin38. Grooved Pin39. Power Input Lever (Airframe

Supplied)40. Actuating Lever41. FCU Control Rod42. Ng Maximum Stop43. FCU Arm Extension44. FCU Control Arm45. Cut-off Valve Lever46. Fuel Control Unit (FCU)47. Hi-idle Stop48. Cut-off Stop49. Serrated Spacer50. Governor Air Pressure Line (Py)51. Cam Follower Lever52. Terminal Housing53. Compression Spring54. Clevis Retaining Bolt



Page 5-1-20May 23/2003

(s) Remove cotterpins (45), castellated nuts (46) and shoulder bolts (57) securingpropeller governor arms (54) to propeller governor actuating lever (58).

NOTE: On engines fitted with spring stop (12), refer to Step (w), following.

(t) Remove cotterpin (45), castellated nut (46), bushing sleeves (53) and bolt (50)securing clevis end of propeller governor actuating lever (58) to propellerreversing lever (17). Remove retaining rings (52) and plain bearing (51) fromlever.

(u) Remove cotterpins (45), castellated nuts (46) plain washers (49) and bolts (56)securing power turbine governor interconnecting rod (20) to power turbinegovernor arm (19) and power turbine governor lever (21).

(v) Remove nut (55) and shoulder bolt (57) securing power turbine governor lever(21) and plain bearings (61) to power turbine governor lever bracket (60)mounted on flange A. Remove self-locking nuts and remove bracket (60) fromflange A.

(w) On engines fitted with spring stop (12), remove two self-locking nuts, bolts andflat washers securing control cylinder and stop spring to engine front liftingbracket (13). Remove control cylinder and stop spring.

NOTE: When removing propeller governor arms (54) (Ref. Step (s),preceding), remove propeller governor arm shield and additionalplain washer.

CAUTION: RELEASE PISTON SLOWLY TO AVOID SUDDEN SPRING ACTIONAFTER REMOVAL OF RETAINING RING.

(x) To disassemble spring stop (12) remove cotterpin and adjust bolt, depressplunger to compress internal springs, then remove spiral retaining ring,piston and two compression springs.

(y) Remove reversing lever guidepins (59) and washers (49) from thrust bearingcover.

(3) Remove propeller reversing front linkage (PT6A-20A and PT6A-20B Engines) asfollows: (See Fig. 5-1-7).

(a) Disconnect rear clevis rod end (2) from propeller control cam (1) by removingcotterpin, washer and straight pin.

(b) Loosen self-locking nut on clamping bolt (4) and remove rear wire ropeterminal by unscrewing from wire rope.

(c) Loosen and unscrew coupling nut (7) at front end of wire rope casing from frontswivel joint (19).

(d) Remove cotterpin, nut, spacer and clamp bolt (27) securing clevis rod end (12)to propeller reversing lever (29).



Page 5-1-21May 23/2003

(e) Remove cotterpin, washer and straight headed pin securing propeller reversinglever (29) to Beta control valve clevis (30). Remove control lever and sleevebushing.

(f) Remove cotterpin, castellated nut, washer and bolt securing propeller governorinterconnect rod (14) to propeller governor air bleed link (31).

(g) Remove cotterpin, castellated nut (25) and washer securing upper end ofinterconnect rod (14) to outer end of wire rope clamping bolt (27). Removeinterconnect rod (14).

(h) Pre-SB1185: Remove locknut (20) securing front swivel joint (19) to liftingbracket on flange A. Withdraw front swivel joint complete with wire ropeterminal, pitch stop adjuster (21), and low pitch adjuster stop (24).

1 PT6A-20A engines: this will include solid link assembly and attached wirerope.

2 PT6A-20B engines: this will include terminal housing (52), compressionspring (53) and wire rope.

(i) Post-SB1185: Remove innermost nut and bolt, and loosen remaining nutsecuring retaining plate (26) to lifting bracket (8). Loosen locknut (20) and pivotretaining plate outward. Remove front swivel joint (19) complete with wirerope terminal, pitch stop adjuster (21), low pitch adjuster stop (24).

1 PT6A-20A engines: this will include solid link assembly and attached wirerope.

2 PT6A-20B engines: this will include terminal housing (52), compressionspring (53) and wire rope.

(j) Remove self-locking nut and bolt securing wire rope casing clamp to bracketattached at flange C.

(k) Remove self-locking nut (18), washer and bolt securing wire rope casing (33)to bracket (16) attached to center fireseal.

(l) Remove two self-locking nuts (18) and bolts securing retaining plates, seals,insulation gaskets (17) and angle bracket (16) to center fireseal. Split retainingplates and seals to enable wire rope casing (33) to be withdrawn throughfireseal.

(m) Loosen and remove wire rope casing coupling nut (7) from front end of rearswivel joint (35). Carefully remove clamp, seals, insulation gaskets and anglebracket from casing. Withdraw casing forward through center fireseal.

(n) Remove rear swivel joint (35) from rear fireseal by removing swivel joint locknut(34) located on forward face of rear fireseal.

(o) PT6A-20A engines: disassemble solid link arrangement, removed inSubparagraph (h), preceding, as follows:



Page 5-1-22May 23/2003

1 Remove self-locking nut (28), and spacer from wire rope clamping bolt (27)to release tension on wire rope.

2 Remove wire rope (32) from front linkage assembly by unscrewing wirerope in a counterclockwise direction to disengage rope from clampingbolt (27) internal threads.

3 Remove clamping bolt (27) from wire rope terminal and fork end (12).

4 Remove locknut (23) from low pitch adjuster stop (24). Unscrew adjusterstop from low pitch stop adjuster (21), remove wire rope terminal andhelical compression spring (22), if installed.

5 Remove lockbolt (15) from stop adjuster (21) and swivel joint casing (19).

(p) PT6A-20B engines: disassemble force link arrangement, removed inSubparagraph (h), preceding, as follows:

1 Remove self-locking nut (28), and spacer from wire rope clamping bolt (27)to release tension on wire rope.

2 Remove wire rope (32) from front linkage assembly by unscrewing wirerope in a counterclockwise direction to disengage rope from internalthreads of clamping bolt (27).

3 Remove clamping bolt (27) and slide terminal housing (52) off wire ropeterminal.

4 Remove cotterpin, castellated nut and bolt (54) securing rod end clevis (12)to terminal housing. Remove rod end clevis, terminal sleeve, andcompression spring (53) from housing.

5 Remove locknut (23) securing low pitch adjuster stop (24) to low pitch stopadjuster (21).

6 Unscrew adjuster stop from stop adjuster and remove wire rope terminal.

7 Remove lock bolt (15) from stop adjuster (21) and swivel joint casing.

11. TEMPERATURE COMPENSATOR AND AIR PRESSURE TUBES (Pre-SB1294)

A. Remove temperature compensator and air pressure tubes (See Fig. 5-1-4):

(1) Loosen coupling nuts securing air pressure tube assembly (21) and enrichment airpressure tube (22) to temperature compensator (11).

(2) Remove two locknuts (15) securing temperature compensator to temperaturecompensator bracket (25). Remove compensator.

NOTE: Disassembly and all other relevant overhaul procedures for temperaturecompensator are contained in Bendix Energy Controls (VO6848) OverhaulManual With Parts List, P/N 3020501.



Page 5-1-23May 23/2003

(3) If temperature compensator is to be replaced during assembly, the hexagon plug(13), bulkhead coupling (14) and straight nipple (20) must be removed fromcompensator to facilitate reassembly. Remove preformed packings (12) and (19).

(4) Disconnect coupling nuts of front air pressure tube (24) from air pressure tubeassembly (21) at rear fireseal (10) and flanged elbow (33) on gas generatorcase. Remove air pressure tube assembly and front air pressure tube.

(5) Remove two double-hexagon bolts (34) securing flanged elbow and gasket (32) togas generator case. Remove elbow and gasket.

(6) Remove self-locking nuts and D-head bolts securing temperature compensatorbracket and electrical receptacle (26) to flange G.

(7) Disconnect coupling nut securing enrichment air pressure tube (22) to elbow (17)on fuel control unit. Remove tube complete with temperature compensator bracketassembly.

(8) Disconnect coupling nuts securing governor air pressure rear tube assembly (18) tostraight nipple to rear fireseal and fuel control unit (1). Remove tube assembly.

(9) Disconnect coupling nuts securing governor center air pressure tube assembly (30)to straight nipple at rear (10) and center (29) fireseals. Remove tube assembly.

(10) Disconnect coupling nuts securing governor front air pressure tube assembly (35)to straight nipple at center fireseal and power turbine governor (PT6A-20 PowerTurbine Governor, PT6A-20A and -20B Propeller Governor). Remove tube assemblyloop clamp from flange C, and remove assembly.

(11) Remove locknuts securing straight nipples to center and rear fireseals. Removenipples and preformed packings.

NOTE: If electrical receptacle is found to be unserviceable, remove electricalleads of enrichment air pressure tube from pins A and B of receptacle asfollows: PT6A-20 and -20B, pins A and B, PT6A-20A, pins B and D (Pins Aand C are not used). Remove self-locking nuts and washer (27) andscrews and washers (23) securing receptacle to mounting bracket andremove receptacle.

12. TEMPERATURE COMPENSATOR, ASSOCIATED AIR PRESSURE TUBES AND P3 FILTERASSEMBLY (Post-SB1294)

A. Remove temperature compensator, associated tubes and P3 filter assembly (See Fig.5-1-8):

(1) Remove self-locking nuts and bolts securing seals (6) or (8) and seal retainingplates (5) or (7) to fireseal mount ring; remove seals. Seal retaining platesshould be removed when tube assemblies are removed from engine.

(2) Loosen coupling nuts securing air pressure tube assembly (29) and heated tubeassembly (1) to temperature compensator (18).



Page 5-1-24May 23/2003

(3) Remove two locknuts (27) and (31) securing temperature compensator totemperature compensator bracket (26). Remove compensator.

NOTE: Disassembly and all other relevant overhaul procedures for temperaturecompensator are contained in Bendix Energy Controls (V06848) OverhaulManual With Parts List, P/N 3020501.

(4) If temperature compensator is replaced during assembly, hexagon plug (19),coupling (25) and straight nipple (36) must be removed from compensator to facilitatereassembly. Remove and discard preformed packings (20) and (24).

(5) Disconnect coupling nuts of front air pressure tube (28) from air pressure tubeassembly (29) at rear fireseal mount ring and flanged elbow (22) on gas generatorcase. Remove air pressure tube assembly (29) and front air pressure tube (28).

(6) Remove bolts that secure flanged elbow (22) and gasket (21) to gas generatorcase. Remove elbow and discard gasket.

(7) Remove four self-locking nuts and washers and four bolts and washers securingelectrical connector to bracket (26).

(8) Remove bolt and self-locking nut that secure bracket (35) and clamps (30) totemperature compensator bracket (26). Remove bolt and self-locking nut thatsecure clamps to heated tube leads. Remove clamps from leads.

(9) Disconnect coupling nut on tube assembly (1) at connector on filter housingassembly (14) and connector (25) on temperature compensator (18).

(10) Disconnect coupling nuts of tube assembly (4) at elbow (9) on filter housing (14)and elbow fitting on FCU. Remove tube assembly (4) and tube assembly (1)complete with electrical leads and electrical receptacle attached.

(11) Disconnect leads of relevant heated air pressure tube assembly from electricalreceptacle as follows: (See Fig. 5-1-9).

(a) Remove two clamp screws (5) and remove clamp halves from bell end fitting(4).

CAUTION: ENSURE LEADS OF CABLES DO NOT TURN WHEN UNSCREWINGBELL END FITTING FROM SHELL.

(b) Remove bell end fitting (4) from connector shell (1) and slide fitting and cablesleeve (6) back along cables.

(c) Slide nylon sleeve (3) and rubber insulator (2) back on cables to exposeterminal pins (7).

(d) Using suitable soldering iron, disconnect leads from Pins A and B.

(12) Remove two self-locking nuts, washers, spacers (13, Fig. 5-1-8) and bolts thatsecure filter housing assembly (14) to bracket (26). Remove housing assemblycomplete.



Page 5-1-25May 23/2003

20 36 29

28

2321

22

2625

CENTER FIRESEALMOUNT RING

31

30

30 35

27

34

33

32 15

24

GFLANGE

A19 20 18

REAR FIRESEALMOUNT RING

1 2 312

11

4

F.C.U.

910

13

14

17

16

5 6

5 6

7 878

PRE−SB1195 POST−SB1195

VIEW A

C8140

Temperature Compensator, Air Pressure Tubes and P3 Air FilterFigure 5-1-8

(Post-SB1294)



Page 5-1-26May 23/2003

Key to Figure 5-1-8

1. Heated Tube Assembly2. Straight Nipple3. Preformed Packing4. Heated Tube Assembly5. Seal Retaining Plate (Pre-SB1195)6. Seal (Pre-SB1195)7. Seal Retaining Plate (Post-SB1195)8. Seal (Post-SB1195)9. Elbow Fitting

10. Jam Nut11. Back-up Ring12. Preformed Packing13. Spacer14. Filter Housing Assembly15. Loop Clamp16. Bracket17. Preformed Packing18. Temperature Compensator19. Plug20. Preformed Packing21. Gasket22. Flanged Elbow23. Sealing Sleeve24. Preformed Packing25. Straight Nipple26. Bracket27. Jam Nut28. Insulated Air Pressure Tube29. Air Pressure Tube30. Loop Clamps31. Jam Nut32. Cover33. Preformed Packing34. Filter Element35. 90 Degree Bracket36. Straight Nipple



Page 5-1-27May 23/2003

1 2 3 4

7

5 6

C1865A

Heated Line Wiring Detail (Typical)Figure 5-1-9



Page 5-1-28May 23/2003

(13) Disassemble P3 filter assembly as follows:

(a) Unscrew cover (32) from housing assembly (14) and remove preformedpacking (33), filter element (34) and preformed packing (17). Discard preformedpacking (17).

(b) Pre-SB1277: Discard filter element (34).

(c) Post-SB1277: Clean filter element (34) (Ref. Part 6). Inspect filter element (Ref.Part 7).

(d) Remove nipple (2) from housing (14), and remove preformed packing (3).

(e) Loosen jam nut (10) on elbow fitting (9) at top of housing (14); remove elbow(9), locknut (10), back-up ring (11) and preformed packing (12).

(14) Remove self-locking nuts securing temperature compensator bracket (26) to studsat flange G. Remove bracket (26).

13. FUEL CONTROL UNIT (FCU) AND FUEL PUMP

A. Remove FCU and fuel pump (See Fig. 5-1-4 and 5-1-10):

(1) Disconnect coupling nuts securing fuel inlet hose (40, Fig. 5-1-10) to elbow (14) onoil-to-fuel heater (18) and fuel pump (4, Fig. 5-1-4). Remove hose.

(2) Disconnect coupling nuts securing fuel inlet hose (16) to elbow on FCU (1) andstraight nipple (9) on fuel pump. Remove hose.

(3) Remove three self-locking nuts (5) and plain washers (6) securing fuel pump (4)and FCU to accessory gearbox housing. Withdraw fuel pump with FCU and gasket(7) from mounting studs.

(4) If FCU and/or fuel pump is replaced at reinstallation, remove four self-locking nutsand plain washers (2) securing FCU (1) to fuel pump (4) and remove FCU frompump mounting studs.

(5) Remove and discard coupling (3).

Key to Figure 5-1-9

1. Connector Shell2. Rubber Insulator3. Nylon Sleeve4. Bell End Fitting5. Clamp Screws6. Cable Sleeve



Page 5-1-29May 23/2003

34

33

32 3130

2928

A

2425

26

27

A

39

38

37

3635

ALTERNATE ARRANGEMENT

19

21 22 23

20

12

13

14

1516

17

1840

11

10

9

8

7

6

5

4

12

3

C1706

Oil-to-Fuel Heater, Oil Pressure Relief Valve, Check Valve and TubingFigure 5-1-10



Page 5-1-30May 23/2003

Key to Figure 5-1-10

1. Engine Lifting Bracket2. Compressor Inlet Case3. Bolt4. Washer5. Cover6. Preformed Packing7. Spring8. Spacer (Zero to Four Units)9. Bypass Valve

10. Relief Valve Body11. Preformed Packing12. Washer13. Bolt14. Elbow15. Locknut16. Back-up Ring17. Preformed Packing18. Oil-to-fuel Heater19. Heater Mounting Bracket20. Washer and Self-locking Nut21. Bolt22. Elbow23. Preformed Packing24. Elbow25. Transfer Tube26. Preformed Packing27. Hose28. Elbow29. Locknut30. Back-up Ring31. Preformed Packing32. Bolt33. Tee34. Preformed Packing35. Plug36. Preformed Packing37. Adapter38. Copper Gasket39. Housing40. Fuel Inlet Hose



Page 5-1-31May 23/2003

(6) Remove preformed packing (8) from fuel bypass port in pump or FCU matingflange.

NOTE: When replacing FCU and/or fuel pump, ensure that elbow and straightnipples are removed from rejected units. Note their relative positions tofacilitate reinstallation on new units. Remove preformed packings andpacking retainers.

14. OIL-TO-FUEL HEATER, CHECK VALVE AND ASSOCIATED TUBES

A. Remove oil-to-fuel heater, check valve and associated tubes (See Fig. 5-1-10):

(1) Disconnect coupling nuts of oil inlet hose assembly (27) from elbow (28) on checkvalve housing (39), or alternatively pressure oil-to- fuel heater tee (33), and flangedelbow (24) on oil-to-fuel heater mounting bracket (19). Remove hose assembly.

(2) Remove self-locking nuts (20) and washers securing oil-to-fuel heater and mountingbracket (19) and flange G. Remove mounting bracket complete with oil-to-fuelheater.

(3) Remove three bolts (13) and washers (12) securing oil-to-fuel heater to mountingbracket.

(4) Remove transfer tube (25) from mounting bracket and remove preformed packings(23) and (26).

(5) Remove two bolts (21) securing flanged elbows (22) to mounting bracket. Removepreformed packing (23).

(6) Remove two bolts (32) securing check valve housing (39) or pressure oil-to-fuelheater tee (33) (as applicable), to accessory gearbox housing. Remove preformedpacking (34).

(7) If check valve housing (39) was installed, remove plug (35) and preformed packing(36) from straight adapter (37). Remove straight adapter and preformed packing(38) from check valve housing.

(8) Slacken locknut (29), and remove elbow (28), with locknut (29), back-up ring (30)and preformed packing (31) from check valve housing (39) or tee (33).

NOTE: If oil-to-fuel heater is to be replaced at assembly, remove elbow (14),locknut (15), back-up ring (16) and preformed packing (17) from heater forreinstallation.

15. AIR INLET SCREEN AND INLET FAIRING

A. Remove air inlet screen and inlet fairing (See Fig. 5-1-11):

CAUTION: KEEP INLET AREA CLEAR OF ALL FOREIGN OBJECTS WHICH COULDENTER ENGINE AND CAUSE INTERNAL DAMAGE.

(1) Remove self-locking nuts, washers and bolts securing air inlet screen at 6 o’clockposition. Separate mating flanges and remove screen.



Page 5-1-32May 23/2003

(2) Pre-SB1056: Remove bolts, nuts and plain washers securing upper and lower inletfairing halves (1) at mating flanges.

(3) Post-SB1056 and PT6A-20A engines: Remove bolts and plain washers securingupper and lower inlet fairing halves (1) to mounting brackets (2) at flange F (3).Remove inlet fairing halves and brackets from inlet area.

16. CENTER AND REAR FIRESEALS

A. Remove center and rear fireseals as follows:

(1) Remove self-locking nuts, bolts, and plain washers securing center fireseal andmounting brackets to gas generator case.

(2) Remove self-locking nuts and bolts securing top and bottom halves of centerfireseal and remove both halves of fireseal.

(3) Remove self-locking nuts, bolts and plain washers securing rear fireseal andmounting brackets to compressor inlet case.

(4) Remove self-locking nuts, bolts, Post-SB1441 spacers if applicable, and rearfireseal mount ring halves.

NOTE: SB1441 adds spacers between upper and lower mount ring mountingbracket.

(5) Remove self-locking nuts and bolts securing mounting brackets and seals tofireseal mount ring halves, remove mounting brackets and seals.

17. COMPRESSOR BLEED VALVE

A. Remove compressor bleed valve as follows:

(1) Remove two bolts securing bleed valve transfer tube flanged elbow to gasgenerator case.

(2) Remove bolts and plain washers attaching bleed valve to gas generator case.

(3) Withdraw compressor bleed valve, complete with transfer tube and flanged elbow,from engine.

18. DIPSTICK AND OIL FILLER TUBE

A. Remove dipstick and oil filler tube as follows:

(1) Unlock and remove oil filler cap and dipstick assembly.

(2) Remove retaining ring attaching filler tube assembly to accessory gearbox housingand withdraw tube assembly complete with preformed packings.



Page 5-1-33May 23/2003

1

2

3

5

4

C1600

Compressor Inlet Area - Inlet Screen RemovedFigure 5-1-11



Page 5-1-34May 23/2003

ENGINE - GENERAL

19. OIL FILTER ELEMENT, HOUSING AND CHECK VALVE (Pre-SB1247)

A. Remove oil filter element, housing and check valve (See Fig. 5-1-12 and 5-1-13):

(1) Remove self-locking nuts and washers attaching oil filter cover (6, Fig. 5-1-12) tocompressor inlet case, and remove cover complete with spacer (5). Removepreformed packing (4).

(2) On Post-SB1118 and PT6A-20A engines, remove filter element (2) using Puller(PWC30556), and remove preformed packings (1 and 3). On Pre-SB1118engines, remove and discard filter element.

(3) Remove oil filter housing (3, Fig. 5-1-13) from compressor inlet case using Puller(PWC30328) (4).

(4) Compress check valve spring (16, Fig. 5-1-12), and remove dowel pin (14) andspring retainer collar (15).

CAUTION: EXERCISE CARE WHEN REMOVING CHECK VALVE TO PREVENTDAMAGE TO VALVE FACE.

(5) Remove check valve spring (16) and washer (20) if fitted, and withdraw valve (7)and bypass valve assembly from oil filter housing (17).

(6) Compress bypass valve spring (8) and remove cotterpin (12). Remove washer (11),bypass valve piston (10), preformed packing (9) and spring (8) from check valve(7).

(7) Pre-SB1127: Remove preformed packing (19) and packing retainer (18) from oilfilter housing.

(8) Post-SB1127 and PT6A-20A Engines: Remove preformed packing (19) and plasticring (21).

(9) Remove preformed packing (13) from oil filter housing (17).

20. OIL FILTER ELEMENT, HOUSING AND CHECK VALVE (Post-SB1247)

A. Remove oil filter element, housing and check valve (See Fig. 5-1-14):

(1) Remove nuts (8), washers (7), cover (6), spacer (5) and preformed packing (4).Discard packing.


1. Inlet Fairing2. Fairing Mounting Bracket3. Flange F (Reference)4. Rear Fireseal5. Engine Inlet (Reference)



Page 5-1-35May 23/2003

1

2

3

4

5

6

7

8

9

10

11

12

18

19

1314

1516

17

20

C1342C

Oil Filter, Housing and Check ValveFigure 5-1-12

(Pre-SB1247)



Page 5-1-36May 23/2003

(2) Remove oil filter element (2) using Puller (PWC30556).

(3) Remove and discard preformed packings (1 and 3).

(4) Remove oil filter housing (23) using Puller (PWC30328).

(5) Remove and discard preformed packings (21 and 24) and plastic ring (22).

(6) Remove retaining ring (25) and check valve assembly (26).

(7) Remove and discard preformed packing (20).

WARNING: ASSEMBLY IS UNDER SPRING PRESSURE. RESTRAIN ASSEMBLYWHEN REMOVING RETAINING RING.

(8) Remove retaining ring (14), valve housing (19), check valve (17) and spring (16).

(9) Remove and discard preformed packing (18).

WARNING: ASSEMBLY IS UNDER SPRING PRESSURE. RESTRAIN BYPASS VALVEWHEN REMOVING COTTERPIN.

(10) Remove cotterpin (9), washer (10), bypass valve (11), spring (13) and packing (12).Discard packing and cotterpin.


1. Preformed Packing (Post-SB1118 and PT6A-20A Engines)2. Filter Element3. Preformed Packing4. Preformed Packing5. Teflon Spacer6. Cover7. Check Valve8. Bypass Valve Spring9. Packing

10. Bypass Valve Piston11. Cotterpin13. Preformed Packing14. Dowel Pin15. Collar16. Check Valve Spring17. Filter Housing18. Back-up Ring (Pre-SB1127)19. Preformed Packing20. Repair Washer (MS9321-08)21. Plastic Ring (Post-SB1127) and PT6A-20A Engines (Not

Illustrated)



Page 5-1-37May 23/2003

1 2 3 4

PLASTIC RING

PREFORMED PACKING

C25

Removal of Oil Filter Housing and Check ValveFigure 5-1-13



Page 5-1-38May 23/2003

21. OIL PRESSURE RELIEF VALVE

A. Remove oil pressure relief valve (See Fig. 5-1-10):

CAUTION: BEFORE REMOVING BOLTS, HOLD COVER AGAINST SPRINGPRESSURE.

(1) Remove bolts (3) and washers (4) securing pressure relief valve cover (5) tocompressor inlet case (2).

(2) Remove cover using Puller (PWC30046-53). Remove preformed packing (6) andrelief valve spring (7).

(3) Withdraw pressure relief valve assembly from inlet case.

(4) Remove spacer(s) (8) (if any) and pressure relief bypass valve (9) from relief valvebody (10). Remove preformed packing (11).

22. EXTERNAL SCAVENGE PUMP - WITHOUT VACUUM PUMP DRIVE

A. Remove external scavenge oil pump from accessory gearbox housing (See Fig.5-1-15):

(1) Remove four self-locking nuts and washers securing rear housing assembly (1) andspacer (4) to front housing (8). Remove rear housing assembly, complete withspacer and long spur gears (2), from front housing.

(2) Remove spacer (4) and two long spur gears from rear housing assembly (1).Remove preformed packings (3).

(3) Remove two short spur gears (7), retaining collars (15) and drive shaft (14) anddrive shaft coupling (5) from front housing.

(4) Remove two self-locking nuts and plain washers and two plain nuts and keywasherssecuring front housing to accessory gearbox mounting pad studs. Withdraw housingfrom mounting studs and remove preformed packing (9).

(5) Remove oil deflector (11) from accessory gearbox housing. Remove preformedpackings (12) from front housing (8).


1. Oil Filter Cover Mount Pad2. Check Valve Cover3. Filter Housing4. Filter Housing Puller (PWC30328)



Page 5-1-39May 23/2003

SECTION A−A

1

2524

INLET CASE

23

2221

2019

1817

1615

1413

12

11

A

A

10

9

26

2

34

5

6

7

8

C10454

Oil Filter, Housing and Check Valve - Exploded ViewFigure 5-1-14

(Post-SB1247)



Page 5-1-40May 23/2003

23. EXTERNAL SCAVENGE OIL PUMP - WITH VACUUM PUMP DRIVE

A. Remove external scavenge oil pump from accessory gearbox housing (See Fig.5-1-15):

(1) Remove four self-locking nuts and washers securing accessory drive cover (21)and gasket (20) to scavenge pump. Remove cover and gasket from mountingstuds.

(2) Remove oil seal retainer (19) from scavenge pump housing assembly (1) usingPuller (PWC30046-52) and press seal (17) out of retainer. Remove preformedpacking (18).

(3) Remove four nuts and washers and two D-head bolts (13) securing scavenge pumprear housing assembly (1) and scavenge pump spacer (4) to scavenge pumphousing (8).


1. Preformed Packing2. Filter Element3. Preformed Packing4. Preformed Packing5. Spacer6. Oil Filter Cover7. Washer8. Nut9. Cotterpin

10. Washer11. Bypass Valve12. Packing13. Spring14. Retaining Ring15. Bypass Valve Guide16. Spring17. Check Valve18. Preformed Packing (Pre-SB1379)19. Check Valve Housing20. Preformed Packing21. Preformed Packing22. Plastic Ring23. Oil Filter Housing24. Preformed Packing25. Retaining Ring26. Check Valve Assembly



Page 5-1-41May 23/2003

6

16 17 18 19 20 21

13

❉ ❉ ❉ ❉

NOTEON ENGINES WITH VACUUM PUMP DRIVE, PARTS MARKED

ARE REQUIRED IN PLACE OF ITEMS 5, 14 AND 15

❉

14 7 21211

❉105

6 7

389

4

15

3 21

C771B

External Scavenge Oil PumpFigure 5-1-15



Page 5-1-42May 23/2003

(4) Remove spacer (4), drive shaft coupling (16), two long spur gears (2) and collars (6)from rear housing assembly.

(5) Remove two short spur gears (7) from scavenge pump front housing (8).

(6) Remove two self-locking nuts and plain washers and two nuts and keywasherssecuring scavenge pump front housing to accessory gearbox mounting padstuds. Withdraw housing from mounting studs and remove preformed packing.

(7) Remove scavenge pump coupling (10) and oil deflector (11) from accessorygearbox housing. Remove preformed packing (12) from front housing (8).


1. Scavenge Pump Housing Assembly - Rear2. Spur Gears3. Bolt4. Preformed Packing5. Spacer6. Drive Shaft Coupling7. Spur Gears8. Scavenge Pump Housing Assembly - Front9. Preformed Packing

10. Scavenge Pump Coupling11. Oil Deflector12. Preformed Packing13. D-head Bolt14. Drive Shaft15. Drive Shaft Collar16. Drive Shaft17. Seal18. Preformed Packing19. Oil Seal Retainer20. Vacuum Pump Mounting Gasket21. Accessory drive Cover



Page 5-1-43May 23/2003

24. ACCESSORY GEARBOX (Post-SB1045, Pre-SB1104, Post-SB1134 AND PT6A-20AENGINES)

A. Remove and split accessory gearbox (See Fig. 5-1-16):

NOTE: 1. On PT6A-20 engines PC-E20361, and PC-E20380 to PC-E20402, accessorygearbox alignment is controlled by two additional 0.125 inch diameter dowelsbetween inlet case and accessory diaphragm. A number of enginessubsequent to PC-E20402 also embody similar but longer dowels, and atdifferent locations. These dowels must be retained for subsequent reassemblyof accessory gearbox to ensure original alignment.

NOTE: 2. Before removing gearbox, ensure that No. 2 bearing internal scavengetransfer tube and oil filter housing have been extracted from compressor inletcase. (Ref. Paragraphs 7. or 8. and 19., preceding.)

CAUTION: Diaphragm assembly is secured to rear housing assembly by fourcountersunk head screws (11), self-locking nuts (29) and washers (28). Thenuts are 4th, 8th, 14th and 18th in clockwise rotation, assuming numberone to be at the 12 o’clock position, and must not be removed at this stage.

(1) Remove self-locking nuts (32), washers (31) and spacers (30) securing rearhousing assembly (15) and diaphragm assembly (9) to compressor inlet case atflange G. Remove rear lifting bracket (14).

(2) Remove center boss hexagon plug (34) and preformed packing (33) from rearhousing and determine location of ball-lock by viewing through center boss hole.Rotate compressor until slot on washer at rear hub is at 3 o’clock position. This willensure that ball in locking arrangement is at top of rear splined end of inputcoupling shaft (1) prior to disengagement.

(3) Install Pusher (PWC30373) through housing center boss into input coupling shaft.Tighten nut on pusher to take up all slackness on input coupling shaft. This willprevent unnecessary loading of support bearing rollers during gearbox removal.

(4) Using four Jackscrews (PWC30226), separate rear housing (15) together withdiaphragm (9) from compressor inlet case. Withdraw gearbox slowly rearwards,keeping it horizontal until completely clear of case

(5) Remove ball from splined end of compressor rear hub.

NOTE: If ball has dropped out of locking arrangement during removal, retrieve itfrom No. 1 bearing housing area or oil scavenge passage in compressorinlet case.

(6) Remove preformed packing (3) from diaphragm (9) at flange G.

(7) Remove oil tank center tube (5) using Puller (PWC32340) and remove preformedpackings (4) and (8).

(8) Remove transfer tubes (7) and (13) from front face of diaphragm, and removepreformed packings (6) and (12) from tubes.



Page 5-1-44May 23/2003

(9) Support accessory gearbox assembly, with diaphragm facing down, on Stand(PWC30517) or on suitable wooden blocks. Remove nuts (29), washers (28)and four countersunk head screws (11) securing housing (15) to diaphragm (9).

(10) Remove bolts (18) securing breather boss cover (17) to housing, and removepreformed packing (16). Remove plug (26) and preformed packing (25).

(11) Push all gearshafts down into gearbox, and lift housing from diaphragm. Removepreformed packing (10).

(12) Remove two oil transfer tubes (20) and (22) and flanged tube (23) from diaphragm.Remove preformed packings (19), (21) and (24) from tubes.

(13) Remove all accessory drive gearshafts (4, 7, 9 and 10, Fig. 5-1-17) and couplings.

25. ACCESSORY GEARBOX (Post-SB1104 AND Pre-SB1134)

A. Remove and split accessory gearbox (See Fig. 5-1-16 and 5-1-17):

NOTE: Before removing gearbox, ensure that No. 2 bearing internal scavenge transfertube and oil filter housing have been removed from engine. (Ref. Paragraphs 7.or 8. and 19., preceding.)

CAUTION: DIAPHRAGM ASSEMBLY (9) IS SECURED TO REAR HOUSINGASSEMBLY (15) BY FOUR COUNTERSUNK HEAD SCREWS (11),SELF-LOCKING NUTS (29) AND WASHERS (28). THESE NUTS ARE4TH, 8TH, 14TH AND 18TH IN CLOCKWISE ROTATION, ASSUMINGNUMBER ONE TO BE AT THE 12 O’CLOCK POSITION, AND MUST NOTBE REMOVED AT THIS STAGE.

(1) Remove self-locking nuts, washers and spacers securing rear housing assembly(15, Fig. 5-1-16) and diaphragm assembly (9) to compressor inlet case at flangeG.

(2) Using four Jackscrews (PWC30226), separate housing (15), together withdiaphragm (9), from compressor inlet case. Withdraw gearbox slowly rearward,maintaining a horizontal position until completely clear.

(3) Remove oil tank center tube (5) and two oil transfer tubes (7) and (13) from front ofdiaphragm. Remove preformed packings (6) and (12) from tubes.

(4) Support gearbox with diaphragm face down, on Stand (PWC30517) or suitablewooden blocks. Remove self-locking nuts (29), washers (28) and countersunkhead screws (11) securing housing to diaphragm.

(5) Remove all accessory drive blanking covers from rear of housing (1, Fig. 5-1-17)and push all gearshafts into gearbox. Lift housing from diaphragm (5). Removepreformed packing.

(6) Remove oil transfer tubes (8) from rear of diaphragm and remove preformedpackings.



Page 5-1-45May 23/2003

22

21

21

19

20

1918

1716

1514

24 23 24

34

33

32

31

3029

28272625

REF. ONLY

COMPRESSORINLET CASE

1213

12

11

12

34

56

76

89 GFLANGE 10

C1601A

Removal of Accessory GearboxFigure 5-1-16



Page 5-1-46May 23/2003


1. Input Coupling Shaft2. Retaining Ring3. Preformed Packing4. Preformed Packing5. Oil Tank Center Tube6. Preformed Packing7. Transfer Tube8. Preformed Packing9. Diaphragm Assembly

10. Preformed Packing11. Countersunk Head Screw12. Preformed Packing13. Transfer Tube14. Lifting Bracket - Rear (PT6A-6B)15. Rear Housing Assembly16. Preformed Packing17. Breather Boss Cover18. Bolt19. Preformed Packing20. Transfer Tube21. Preformed Packing22. Transfer Tube23. Flanged Transfer Tube24. Preformed Packing25. Preformed Packing26. Plug27. Slotted Spacer28. Washer29. Self-locking Nut30. Spacer31. Washer32. Self-locking Nut33. Preformed Packing34. Plug



Page 5-1-47May 23/2003

8

10

9

8

4

5 6

7

1 2

3

13 12 11

14

C934B

Disassembly of Accessory GearboxFigure 5-1-17



Page 5-1-48May 23/2003

(7) Remove all accessory drive gearshafts (4), (7), (9) and (10) and input coupling shaft(3) from housing.

26. INTERNAL SCAVENGE PUMP AND OIL TRAY

A. Remove internal scavenge pump and (Post-SB1122) oil tray from rear housing (SeeFig. 5-1-17):

(1) Remove flexible coupling (14) from internal scavenge pump (13).

(2) Unlock keywashers and remove bolts and keywashers securing oil tray (12) andscavenge pump (13) to rear housing (1).

(3) Withdraw scavenge pump, housings, gears and cover from rear housing.

(4) Unlock keywashers and remove bolts and keywashers securing screen and spacersto scavenge pump inner housing.

27. ACCESSORY DRIVE BEARINGS

A. Remove accessory drive bearings (See Fig. 5-1-17):

(1) Unlock keywashers and remove bolts securing flanged roller bearings (2) torespective bosses.

CAUTION: MAINTAIN RECORD OF ALL BEARING LOCATIONS TO ENSUREREINSTALLATION IN ORIGINAL LOCATIONS.

(2) Remove bearings from their respective bosses. Record bearing serial numbers andlocations on suitable record sheet (see Fig. 5-1-18).


1. Rear Housing Assembly2. Gearbox Drive Bearing (Typical)3. Input Coupling Shaft (Post-SB1104 and Pre-SB1134)4. External Scavenge Pump Drive Gearshaft5. Diaphragm Assembly6. Centrifugal Breather Impeller7. Starter-generator Drive Gearshaft8. Oil Transfer Tube9. FCU Drive Gearshaft

10. Oil Pump Drive Gearshaft11. Optional Accessory Drive Bosses12. Oil Tray (Post-SB1122)13. Internal Scavenge Pump14. Flexible Coupling



Page 5-1-49May 23/2003

REAR VIEWACCESSORY GEARBOX DIAPHRAGM

NOTERECORD SERIAL NO.

IN SPACES PROVIDED

BOSS NO. 1BOSS NO. 6

BOSS NO. 5

BOSS NO. 4

BOSS NO. 1

BOSS NO. 2

BOSS NO. 3

BOSS NO. 2

BOSS NO. 3

BOSS NO. 6

BOSS NO. 5

BOSS NO. 4

FRONT VIEWACCESSORY GEARBOX HOUSING

C1111

Recommended Record Sheet for Drive BearingsFigure 5-1-18



Page 5-1-50May 23/2003

(3) Post-SB1045, Pre-SB1104, Post-SB1134 and PT6A-20A Engines: Remove inputcoupling shaft (1, Fig. 5-1-16) from input drive gearshaft by removing retainingring (2). Remove remaining bearings from diaphragm (5, Fig. 5-1-17).

(4) Post-SB1104 and Pre-SB1134: Remove three bolts and keywashers securing inputcoupling shaft (3) and bearing assembly to housing (1). Remove input couplingshaft and bearing assembly from gearbox housing.

(5) Remove centrifugal breather carbon seal carrier from gearbox diaphragm usingPuller (PWC30052). Remove seal from carrier using Drift (PWC30051-02 )andBase (PWC30051-01).

CAUTION: USE EXTREME CARE WHEN REMOVING AND HANDLING GEARSHAFT,NOT TO SCRATCH OR OTHERWISE DAMAGE CARBON FACE-SEALCONTACTING SURFACE AT END OF SHAFT.

(6) Separate centrifugal breather impeller from starter-generator gearshaft as follows:(See Fig. 5-1-19).

(a) Locate split plate (3) as shown, between centrifugal impeller (5) and gearshaft(6).

(b) Position assembly on base (4).

(c) Install compressor (1) on impeller (5) and mate lugs of compressor with slots inimpeller.

(d) Using drift (2), inserted in compressor, separate assembly.

(e) Remove split plate from impeller and gearshaft from bottom of base.

(f) Remove retaining ring (12, Fig. 5-1-16) and preformed packings (10) and (13)from impeller and gearshaft respectively.

28. ACCESSORY DRIVE SEALS

A. Remove accessory gearbox drive seals as follows:

NOTE: Starter-generator and fuel control unit drive seal carriers are secured ingearbox housing by retaining rings. Remove rings before withdrawing sealcarriers.

(1) Withdraw seal carriers from gearbox housing using Pullers (PWC30046-57) and(PWC30046-52) as applicable.

(2) On Pre-SB1083 engines, remove seals from carriers using applicable Drifts andBases (PWC30048) and (PWC30049). Remove preformed packings.

(3) On Post-SB1083 and PT6A-20A engines, remove seals (by hand) from sealcarriers. Remove preformed packings.



Page 5-1-51May 23/2003

1 1

5 6

7

1 3

4

2

IMPELLER AND GEARSHAFT SEPARATION

COMPRESSOR INSTALLATIONS

C3614

Impeller and Starter Gearshaft - DisassemblyFigure 5-1-19



Page 5-1-52May 23/2003

29. PRESSURE OIL PUMP

A. Remove pressure oil pump from front face of accessory gearbox diaphragm as follows:

(1) Remove bolts and plain washers securing pressure oil pump body to diaphragm.

(2) Withdraw pump body, gears and cover assembly from diaphragm. Remove retainingring securing screen to inlet port on pump body.

(3) Remove oil pump seal and seal carrier from diaphragm using Puller (PWC30046-57).Remove preformed packing.

(4) On Pre-SB1083 engines, remove teflon seal from carrier using Drift and Base(PWC30050).

(5) On Post-SB1083and PT6A-20A engines, remove silicone seal (by hand) from sealcarrier.

30. POWER SECTION

A. Remove power section from gas generator case as follows:

(1) Secure power section Sling (PWC30037) to propeller shaft flange.

(2) Remove interturbine temperature thermocouple (T5) terminal block retaining boltsand push terminal block and gasket into gas generator case.

(3) Remove self-locking nuts and bolts securing gas generator case to exhaust duct(flange C). Carefully withdraw power section from gas generator case.

(4) Install power section on Stand (PWC30039) and secure with nuts and bolts.Remove sling.

31. FUEL MANIFOLD AND FUEL DUMP VALVE

A. Remove fuel manifold and fuel dump valve (See Fig. 5-1-20):

(1) Remove adapter bolts (10) and lockplate (13) securing fuel manifold inlet adapter(9) at 6 o’clock position on gas generator case.

(2) Remove adapter bolts (1) and lockplates (2) from each adjacent manifold adapter(3).


1. Compressor (PWC30855)2. Drift (PWC30854)3. Split Plate (PWC30275)4. Base (PWC30274)5. Centrifugal Impeder6. Starter-generator Gearshaft



Page 5-1-53May 23/2003

6

7

8

9

4 5

3

2

13

12

11

10

14

1

C1750A

Fuel Manifold and Dump ValveFigure 5-1-20



Page 5-1-54May 23/2003

(3) Remove fuel manifold transfer tubes (14), and remove preformed packings fromtransfer tubes.

(4) Remove inlet adapter (9) and attached fuel dump valve (6) as an assembly fromgas generator case. Remove inlet adapter gasket.

(5) Loosen locknut (4) on fuel dump valve tube coupling (5) and remove dump valvefrom inlet adapter.

(6) Remove adapter bolts and lockplates from remaining fuel manifold adapters.

(7) Remove fuel manifold transfer tubes. Remove preformed packings from tubes.

(8) Remove fuel manifold adapters and remove gaskets.

(9) Place adapter assemblies in suitable containers.

NOTE: If dump valve has to be replaced at assembly, remove elbow (8), nut (7),tube coupling (5) and locknut (4) from valve for reinstallation on replacementvalve. Remove packing retainers and preformed packings from elbowand couplings.

32. COMBUSTION CHAMBER LINER AND GAS GENERATOR CASE DRAIN VALVES

A. Remove combustion chamber liner and gas generator case drain valves (See Fig. 5-1-20and 5-1-21):

CAUTION: DO NOT ATTEMPT TO PRY LINER LOOSE.

(1) Withdraw combustion chamber liner (1, Fig. 5-1-21) from gas generator case (2). Ifdifficulty is experienced in withdrawing liner, strike inside of liner sharply with palmof hand.


1. Bolts - Double Hexagon2. Transfer Tube Lockplate3. Manifold Adapter4. Locknut5. Tube Coupling6. Dump Valve7. Locknut8. Elbow9. Inlet Adapter

10. Bolts - Double Hexagon11. Gas Generator Case Front Drain Valve12. Bolts13. Inlet Tube Lockplate14. Transfer Tube



Page 5-1-55May 23/2003

1 2

3

4

C492A

Combustion Chamber LinerFigure 5-1-21



Page 5-1-56May 23/2003

(2) Remove bolts (12, Fig. 5-1-20) securing gas generator front drain valve (11) and reardrain valve to gas generator case. Remove drain valves.

(3) Remove gaskets from each drain valve.

(4) Remove retaining ring from each drain valve and remove valve and spring. Retainparts separately in plastic bags.

33. COMPRESSOR TURBINE SINGLE PLANE BALANCING ASSEMBLY (Pre-SB1043 Engines)

A. Remove turbine disk assembly (See Fig. 5-1-22):

(1) Disengage stubshaft bolt splined lock (5) installed in turbine stubshaft bolt (4) usingPuller (PWC30325) as follows:

(a) Back off puller body (2) until it touches nut on puller screw (1).

(b) Install puller by running puller screw into splined lock (5) until screw bottoms.

(c) Hold puller screw with suitable wrench and run-down puller body (2) until splinedlock is fully disengaged from splines of compressor front stubshaft (6) and bolt(4).

NOTE: The fully disengaged position of splined lock can only be determinedby feel; i.e. when splined lock contacts rear face of turbine stubshaftbolt (4), an increased torque will be felt.

(2) Remove turbine stubshaft bolt (4) using Wrench (PWC30042).

(3) Remove splined lock (5) and compression spring (3) from bolt.

CAUTION: CONTINUED OPERATION OF PULLER IN FOLLOWING STEP MAYCAUSE DAMAGE TO TRAILING EDGE OF BLADES IF HEAT SHIELD ISCONTACTED.

(4) Using Puller (PWC30330), release turbine disk spigot snap diameters only.Withdraw turbine disk assembly.

NOTE: Release of spigot snap diameters will be observed by a drop of disk orfreedom of puller operation.


1. Combustion Chamber Liner2. Gas Generator Cased3. Ignition Glow Plug / Spark Igniter Boss (Reference)4. Ignition Glow Plug / Spark Igniter Locating Hole (Reference)



Page 5-1-57May 23/2003

1 2 3 4 5 6

C1602

Compressor Turbine AssemblyFigure 5-1-22

(Pre-SB1043 Engines)



Page 5-1-58May 23/2003

34. COMPRESSOR TURBINE TWO PLANE BALANCING ASSEMBLY (Post-SB1043 ANDPT6A-20A Engines)

A. Remove compressor turbine assembly (See Fig. 5-1-23):

(1) Install Wrench (PWC30331) (1) at flange C (2) of gas generator case to preventturbine disk from rotating.

(2) Insert teflon Protector Sleeve (PWC30336) (3) into centerbore of turbine assembly(7).

(3) Using Tool (PWC30335) (4), unlock keywasher (5) retaining mounting bolt (6).

(4) Remove unlocking tool and break torque on bolt using conventional socket. Removebolt and keywasher.

NOTE: To facilitate loosening of (Post-SB1439) mounting bolt, apply sufficientapproved penetrating oil (50% kerosene, 50% engine oil is suitable),through center hole in bolt, to flood cavity in stubshaft. Rotate turbine severaltimes, allowing oil to reach slots in bolt thread. Allow oil to soak threadfor 20 minutes before loosening bolt.

(5) Remove wrench from flange C.

CAUTION: CONTINUED OPERATION OF PULLER IN FOLLOWING STEP MAYCAUSE DAMAGE TO TRAILING EDGE OF BLADES IF HEAT SHIELD ISCONTACTED.

(6) Using Puller (PWC30403) (8), release turbine disk snap diameter only. Withdrawturbine assembly.

NOTE: Release of spigot snap diameters will be observed by a drop of disk orfreedom of puller operation.

35. COMPRESSOR TURBINE VANES, SHROUD SEGMENTS, SHROUD HOUSING ANDSMALL (INNER) EXIT DUCT

A. Remove compressor turbine vanes, shrouds, shroud housing and small (inner) exit ductassembly (See Fig. 5-1-24):

(1) Pre-SB1172: Remove and discard eight bolts (12) securing turbine vane innersupport (10), combustion chamber small and large exit ducts (13) and (7) toNo.2 bearing cover in gas generator case.


1. Screw (Part of Puller PWC30325)2. Body (Part of Puller PWC30325)3. Helical Compression Spring4. Turbine Stubshaft Bolt5. Stubshaft Bolt Splined Lock6. Compressor Front Stubshaft



Page 5-1-59May 23/2003

1

2

4

8

5

6

1

4

3

7

C1603

Compressor Turbine AssemblyFigure 5-1-23



Page 5-1-60May 23/2003

(2) Post-SB1172 and PT6A-20A Engines: Remove and discard eight bolts (12) securingcompressor turbine vane support clamp (11), turbine vane inner support (10), smalland large exit ducts (13) and (7) to No.2 bearing cover in gas generator case.

(3) Withdraw assembly of small exit duct, turbine vane inner and outer supports (10)and (6), vane (9) shroud housing (2) and shroud segments (4), from No.2 bearingcover.

(4) Remove twelve bolts (1) securing T4 cable and thermocouple assembly shroudhousing (2) and turbine vane outer support (6) to small exit duct (13). Removeshroud housing from assembly.

(5) Remove heat shield (3) from shroud housing.

(6) Remove V-shaped packing (5) from turbine vane outer support (6).

(7) Remove compressor turbine vanes (9) from turbine vane inner support (10). Storevanes in individual containers to protect them from damage.

(8) Remove ceramic fiber cord (8) from front outer groove on vane inner support (10).

(9) On Pre-SB1147 engines, remove four shroud segments (4) from turbine shroudhousing.

(10) On Post-SB1147 and Post-SB1163and PT6A-20A Engines engines, removefourteen compressor turbine shroud segments (4) from turbine shroud housing.

36. COMPRESSOR TURBINE BLADES

A. Remove blades from compressor turbine assembly (See Fig. 5-1-25):

(1) Prepare Blade retaining rivet drilling fixture (PWC38296) as follows (Ref. Fig.5-1-25):

(a) Install Drill bit (1) (PWC38293) in chuck (2).

NOTE: Using drill gage (17) on column (18), ensure diameter of drill bitselected is required size.

(b) Connect compressed air supply to inlet of pedal valve (19).


1. Wrench (PWC30331)2. Flange C3. Protector Sleeve (PWC30336)4. Unlocking Tool (PWC30335)5. Keywasher6. Mounting Bolt7. Turbine Assembly8. Puller (PWC30403)



Page 5-1-61May 23/2003

13 12 1110

9 8

7

1 2 34

5

6

C1604

Compressor Turbine Vanes, Shroud Segments, Shroud Housing and Exit DuctsFigure 5-1-24



Page 5-1-62May 23/2003

(c) Depress foot pedal and gradually open air regulator valve (3) until airpressure reads 20 psig on gage (4).

(d) Insert disk (10) in bore of Disk Support (8) (PWC32251). Secure with pad (23)and knurled nut (7).

(e) Install disk (10)/disk support (8) assembly in cradle (20), and secure with screw(6).

NOTE: If necessary, release screw (5) and rotate cradle (20) sufficiently togain access to screw (6). Tighten screw (5).

(f) Release screw (5) and allow cradle (20) to settle at zero degree position onprotractor (9).

(g) Position cradle (20) at an angle of plus 26 degrees 30 minutes as indicated onprotractor (9). Tighten screw (5).

NOTE: When facing protractor, positive angle is obtained by rotating cradle tothe left of fixed zero degree, negative angle to the right (Ref. Fig.5-1-25, View C).

CAUTION: RIVET AND DRILL MUST BE CENTRALIZED TO ENSURE DAMAGETO DISK DOES NOT OCCUR.

(h) Release screw (11), and slide assembly to bring rivet under drill bit (1).Centralize rivet by rotating disk and sliding assembly laterally until drill bit iscorrectly aligned in rivet hole. Tighten screw (11).

(2) Set drill cutting depth as follows (Ref. Fig. 5-1-25, View A):

(a) Loosen knob (12) if necessary, and move gage (13) away from rod (14).


1. Bolt2. Compressor Turbine Shroud Housing3. Heat Shield4. Shroud Segments5. Packing6. Vane Outer Support7. Large (Outer) Exit Duct8. Ceramic Fiber Cord9. Turbine Vane

10. Vane Inner Support11. Support Clamp (Post-SB1172 and PT6A-20A Engines)12. Bolt13. Small (Inner) Exit Duct



Page 5-1-63May 23/2003

A

B

1416

12

1315

21

2

1

7

2310

17

4

3

822

95

11

2018

19

6

NOTE: THIS ILLUSTRATION SHOWS A TYPICAL EXAMPLE OF A FLARED RIVET HEADDRILLING INSTALLATION. ANGLE OF DISK NOT ILLUSTRATED FOR CLARITY.

C41722A

Compressor Turbine Blade RemovalFigure 5-1-25 (Sheet 1 of 2)



Page 5-1-64May 23/2003

VIEW A

VIEW BVIEW C

C

POSITIVE NEGATIVE

NOTE: VERNIER PROTRACTOR SET AT20 DEG. 15 MIN. POSITIVE ANGLE (EXAMPLEONLY, REFER TO TEXT FOR CORRECTANGULAR SETTING)

CONTACTING ROD AWAY FROM ROD

0.090 IN.

FLARED RIVET HEADCENTRALIZED WITH DRILLBIT

FLARED RIVET HEADDRILLED TO REQUIRED DEPTH

GAGE POSITIONS WITH CORRESPONDING DRILL POSITIONS

CL CL

1416

1512

13

C41723A

Compressor Turbine Blade RemovalFigure 5-1-25 (Sheet 2)



Page 5-1-65May 23/2003


1. Drill Bit2. Chuck3. Air Regulator Vale4. Gage5. Screw6. Screw7. Knurled Nut8. Disk Support9. Protractor

10. Disk11. Screw12. Knob13. Gage14. Rod15. Nut16. Nut17. Drill Gage18. Column19. Pedal Valve20. Cradle21. Lever22. Piston Brake23. Pad



Page 5-1-66May 23/2003

(b) Using lever (21), position drill bit (1) to contact centralized flared rivet headand, holding drill in that position, slide gage (13) to contact rod (14).

(c) Turn nut (15) to just make contact with gage (13).

(d) Slide gage (13) away from rod (14), release lever (21), and tighten nut (16) tolock nut (15) in position.

(e) Secure gage (13) in position away from rod (14) with knob (12).

(f) With drill retracted, depress pedal valve (19). Ensure drill is rotating and pistonbrake (22) is functioning (disk cannot rotate). Release pedal valve.

(3) Drill rivets as follows:

WARNING: WEAR PROTECTIVE EYE GOGGLES WHEN DRILLING RIVETHEADS.

(a) Apply one drop of engine oil to each flared rivet head.

(b) Ensure rivet is centralized (Ref. Step (1) (h), preceding).

(c) With drill retracted, depress pedal valve (19). Drill rivet, retract drill and releasepedal valve.

(d) Repeat Steps (b) and (c) until all rivets are drilled.

(e) Loosen screw (6), and remove disk (10)/disk support (8) assembly from cradle(20). Install assembly on Base (PWC38288).

(4) Remove turbine blades as follows:

CAUTION: USE EXTREME CARE DURING RIVET REMOVAL TO AVOIDMARKING OR OTHERWISE DAMAGING DISK.

(a) Using Punch (PWC38297) and suitable hammer, tap on drilled rivet head untilflare shears. Remove rivet.

NOTE: Some blades may fall out of disk with rivet.

(b) Repeat Step (a) until all rivets are removed.

(c) Using suitable fiber drift, remove blades by tapping lightly at fir tree root.

(d) Place blades (4) in container, preferably with individual compartments forprotection against possible damage during overhaul.

(e) Remove disk (10)/disk support (8) assembly from Base (PWC38288);disassemble knurled nut (7) and pad (23); and remove disk (10) from bore ofdisk support (8).

(5) Remove balance weights, retaining rivets and balance rivets as follows :

(a) Place disk on suitable wood or fiber supports.



Page 5-1-67May 23/2003

(b) Remove balance weights , retaining rivets and balance rivets from disk rims byremoving outer heads of rivets with flat chisel, then punching out shanks with0.062 inch diameter drift.

(c) Place disk in container for protection against possible damage during overhaul.

37. COMBUSTION CHAMBER LARGE (OUTER) EXIT DUCT

A. Remove combustion chamber large (outer) exit duct (See Fig. 5-1-24):

(1) Apply hand pressure evenly on each side of centerbore of large exit duct (7) andsimultaneously rotate duct counterclockwise approximately 20 degrees to disengageit from support brackets in gas generator case.

(2) Withdraw duct from gas generator case.

38. COMPRESSOR INLET CASE

A. Remove compressor inlet case as follows:

(1) Install splined end of Loading Wrench (PWC30716) in centerbore of compressorfront stubshaft and locate wrench on gas generator case at flange C. Fastenwrench with four bolts and wing nuts. Adjust loading bar of wrench to eliminateslack without pre-loading compressor assembly.

CAUTION: UNDER NO CIRCUMSTANCES DO NOT ROTATE COMPRESSORASSEMBLY.

(2) Rotate gas generator case on stand, so that flange C faces down.

(3) Remove four bolts and plain washers securing No. 1 bearing outer housing tocenterbore of compressor inlet case.

(4) Remove all but four self-locking nuts from compressor inlet case and gas generatorcase using Wrench (PWC30114-03).

NOTE: The four remaining nuts are to be equally spaced and flush with studends, to act as pushers during later stage of disassembly.

(5) Install Ring (PWC30231) on rear outside diameter (cone end) of gas generatorcase, and back off four self-locking nuts sufficiently to contact ring.

(6) Insert four Jackscrews (PWC30223) into compressor inlet case at centerbore ofNo. 1 bearing. Increase pressure evenly on jackscrews and four self-locking nutsuntil compressor inlet case separates from gas generator case.

(7) Remove compressor inlet case and place it on bench with flange G facing up.

(8) Remove Ring (PWC30231) and Jackscrews (PWC30223) from gas generator caseand compressor inlet case respectively.



Page 5-1-68May 23/2003

(9) Remove two bolts and withdraw No. 1 bearing oil nozzle assembly from compressorinlet case. Remove retaining ring, oil jet filter and preformed packing from nozzleassembly.

(10) Remove engine trim speed plate and identification plate.

39. NO. 1 BEARING

A. Remove No. 1 bearing from gas generator case (See Fig. 5-1-26):

(1) Remove compressor inlet locating disk from rear face of compressor assembly.Locate Protector (PWC30221) on compressor first stage vane and shroudassembly.

(2) On Pre-SB1094 engines, remove four bolts and washers securing bearing outerhousing (15) to No. 1 bearing seal cover (2) using Wrench (PWC30114-02).

(3) On Post-SB1094 and PT6A-20A engines, remove four bolts securing bearing outerhousing (15) to compressor rear stator air seal (2) using Wrench (PWC30114-02).

(4) Remove five bolts and keywashers securing bearing outer housing (15) to No. 1bearing flexible support (14) and adapter (11) assembly.

(5) Remove five bolts and keywashers securing No. 1 bearing flexible support (14) tobearing adapter (11). Withdraw bearing outer housing and flexible support.

(6) Install compressor rotor Support Fixture (PWC30233).

(7) Unlock cupwashers (12) and remove spanner nut (13) and cupwasher securingNo. 1 bearing rear split inner race (10) to compressor rear hub (1) using Wrench(PWC30716) and Socket (PWC30585).

(8) Remove No.1 bearing rear split inner race (10) using Puller (PWC30085).

(9) Withdraw No.1 bearing and bearing adapter (11). Remove bearing from adapter asfollows:

(a) Install bearing adapter in Support (PWC30586 ) and unlock keywasher (6).

(b) Remove spanner nut (5) and keywasher securing No.1 bearing outer race (9)in bearing adapter using Socket (PWC30115).

(c) Withdraw No.1 bearing outer race and ball and cage (8).

(10) Remove No.1 bearing front split inner race (7) using Puller (PWC30085) andremove adjusting spacer (4) from compressor rear hub (1).

(11) Remove rear stator air seal (2) (Post-SB1094 and PT6A-20A engines), or No.1bearing seal cover (Pre-SB1094), and remove preformed packing (3).

(12) Remove Protector (PWC30221) from gas generator case.



Page 5-1-69May 23/2003

1112

1314

15

17

16

12

34

5 6 78

910

C1859

No. 1 Bearing RemovalFigure 5-1-26



Page 5-1-70May 23/2003

40. COMPRESSOR ROTOR (Pre-SB1094)

A. Remove compressor rotor assembly from gas generator case as follows:

(1) Install Holding Fixture (PWC30232) over compressor rear nuts and secure it withspanner nut (13, Fig. 5-1-26).

(2) Unlock keywashers and, using Wrench (PWC30114-01), remove nuts securingimpeller housing to gas generator case.

(3) Using Wrench (PWC30114-04), remove eight impeller housing attachment bolts,thrust washers and lockplates.

(4) Install Puller (PWC30109) on gas generator case and attach split puller to rear hubcoupling. Withdraw rotor assembly from gas generator case

(5) Install compressor rotor assembly on Stand (PWC30455), and remove Puller(PWC30109) and Holding Fixture (PWC30232).

B. Disassemble compressor rotor assembly as follows:

CAUTION: TO AVOID ANY DISTORTION OF COMPRESSOR COMPONENTS,LOOSEN DIAMETRICALLY OPPOSITE TIE ROD NUTS IN INCREMENTSOF 1/4 TURN UNTIL ALL TENSION IS RELIEVED.

(1) Unlock keywashers (1, Fig. 5-1-27) and slacken nuts (2) using Wrench (PWC30414)(4).


1. Compressor Rear Hub2. Compressor Rear Stator Air Seal (Post-SB1094 Engines)

No.1 Bearing Seal Cover (Pre-SB1094 Engines)3. Preformed Packing4. Adjusting Spacer5. Spanner Nut6. Keywasher7. No. 1 Bearing Front Split Inner Race8. No. 1 Bearing Balls and Cage Assembly9. No. 1 Bearing Outer Race

10. No. 1 Bearing Rear Split Inner Race11. Bearing Adapter12. Cupwasher13. Spanner Nut14. Flexible Support15. Bearing Outer Housing16. Bolt and Washer17. Bolt and Washer



Page 5-1-71May 23/2003

4

5

2

1

3

C3215

Compressor Tie Rod RemovalFigure 5-1-27



Page 5-1-72May 23/2003

(2) Remove nuts, keywashers and six tie rods (3).

(3) Install Puller (PWC30819) (1, Fig. 5-1-28) on compressor hub, locate feet in hubholes ensuring that offset foot is in offset hole in hub. Secure puller with spannernut (2).

(4) Separate hub from first stage spacer by tightening evenly on three screws (3) untilhub is released. Using handles (4), lift hub assembly from compressor rotor.Remove spanner nut and puller from hub.

(5) Remove first stage compressor blades (24, Fig. 5-1-29) from hub (33), and placethem in a suitable container.

(6) Withdraw compressor breather tube (22) from center bore of compressor rotor.Remove preformed packings (23 and 21).

(7) Remove first stage vane and shroud assembly (34) by prying it off evenly.

(8) Remove first stage compressor spacer and sleeve assembly (13) using Puller(PWC30277) (face A uppermost), Adapter Plug (PWC30278) and three Inserts(PWC30280).

(9) Remove second stage compressor blades (12) from disk (14) and place in asuitable container.

(10) Remove second stage compressor disk using Puller (PWC30152).

(11) Remove second stage vane and shroud assembly (15) by prying it off evenly.

(12) Remove second stage compressor spacer and sleeve assembly (16) usingPuller(PWC30277) , Adapter Plug (PWC30278) and three Inserts (PWC30280).

(13) Remove third stage compressor blades (11) from disk (17) and place in a suitablecontainer.

(14) Remove third stage compressor disk (17) using Puller (PWC30152).

(15) Remove third stage vane and shroud assembly (18) by prying it off evenly.

(16) Remove third stage compressor spacer and sleeve assembly (19) using Puller(PWC30277) (face B uppermost), Adapter Plug (PWC30279) and three Inserts(PWC30181).


1. Keywasher2. Nut3. Tie Rod4. Wrench (PWC30414)5. Compressor Hub



Page 5-1-73May 23/2003

2

43

1

5

6

7

8

C3216

Compressor Rear Hub RemovalFigure 5-1-28



Page 5-1-74May 23/2003

(17) Remove centrifugal impeller from stand and place impeller with leading edge facedown on bench.

(18) Remove rotor air seal (10) and No. 2 bearing inner race using Puller (PWC30489).

(19) On Pre-SB1043 engines, remove compressor front stubshaft rotor air seal fromfront stubshaft using Puller (PWC30350).

(20) Remove compressor front stubshaft (6) from impeller using Puller Rod (PWC30366)and Adapter Body (PWC30368) for Pre-SB1043 engines or Puller Rod (PWC30367)and Adapter Body (PWC30368) for Post-SB1043 engines.

(21) Remove compressor rotor air seal from rear hub using Puller (PWC30108).

CAUTION: USE EXTREME CARE WHEN REMOVING BALANCING WEIGHTS TOPREVENT DAMAGING RETAINING RING. GOUGING AND CRACKING OFRING ARE NOT ACCEPTABLE AND ARE REASON FOR REJECTIONOF RING.

(22) Remove all balancing rivets and balance weights (26) and (25) from compressorrear hub. Retain balance weights.

(23) Remove counterweight balancing bolts (5) and keywashers (4) from front stubshaft.Discard bolts and keywashers.

41. COMPRESSOR ROTOR (Post-SB1094 AND PT6A-20A ENGINES ENGINES)

A. Remove compressor rotor assembly from gas generator case as follows:

(1) Install Holding Fixture (PWC30420) and secure to compressor rear hub withspanner nut (13, Fig. 5-1-26).

(2) Unlock keywashers and remove eight nuts securing impeller housing to gasgenerator case using Wrench (PWC30114-01).

(3) Remove eight impeller housing bolts, six washers and two lockplates using Wrench(PWC30114-04).

(4) Remove holding fixture and withdraw compressor rotor from gas generator caseusing Puller (PWC30109).


1. Puller (PWC30819)2. Spanner Nut3. Screw4. Handle5. First-Stage Compressor Stator Assembly6. Nut and Bolt7. Third-Stage Compressor Stator Assembly8. Impeller Housing



Page 5-1-75May 23/2003

2426

25 27

2829

34 33

32

31 30

17 16

131415

20

19 182123 22

32

1

10 9 8 7 6 54

C1901

Compressor Rotor AssemblyFigure 5-1-29

Pre-SB1094



Page 5-1-76May 23/2003


1. Tie Rod2. Performed Packing3. Centrifugal Impeller4. Keywasher5. Bolt - Counterweight Balance6. Front Stub7. No. 2 Bearing8. Keywasher9. Bolt

10. Rotor Air Seal11. Third Stage Compressor Blades12. Second Stage Compressor Blades13. First Stage Disk Spacer14. Second Stage Compressor Disk15. Second Stage Stator Vane and Shroud Assembly16. Second Stage Disk Spacer17. Third Stage Compressor Disk18. Third Stage Shroud Assembly19. Third Stage Disk Spacer20. Impeller Housing21. Preformed Packing22. Compressor Breather Tube23. Preformed Packing24. First Stage Compressor Blades25. Balance Weight26. Balance Weight Rivet27. Rivet Final Balancing28. Keywasher29. Nut30. Rear Rotor Air Seal31. Rear Hub Coupling32. Straight Pin33. Compressor Rear Hub Assembly34. First Stage Vane and Shroud Assembly



Page 5-1-77May 23/2003

(5) Remove puller and install compressor rotor in Stand (PWC30455) with rear hubfacing up.

B. Disassemble compressor rotor assembly (See Fig. 5-1-30):

CAUTION: TO AVOID ANY DISTORTION OF COMPRESSOR COMPONENTS,LOOSEN DIAMETRICALLY OPPOSITE TIE ROD NUTS IN INCREMENTSOF 1/4-TURN UNTIL ALL TENSION IS RELIEVED.

(1) Unlock keywashers (1, Fig. 5-1-27) and slacken nuts (2) using Wrench (PWC30414)(4).

(2) Remove nuts, keywashers and six tie rods (3).

(3) Install Puller (PWC30819) (1, Fig. 5-1-28) on compressor hub, locate feet in hubholes ensuring that offset foot is in offset hole in hub. Secure puller with spannernut (2).

(4) Separate hub from first stage spacer by tightening evenly on three screws (3) untilhub is released. Using handles (4), lift hub assembly from compressor rotor.Remove spanner nut and puller from hub. Place hub on bench with blade trailingedges uppermost.

(5) Remove first stage blades (12, Fig. 5-1-30) from hub assembly and place insuitable container.

(6) Withdraw compressor breather tube (5) from centerbore of compressor. Removepreformed packings (4).

(7) Remove first stage vane and shroud assembly (25) by prying off evenly.

(8) Remove first stage disk spacer (24) using Puller (PWC30501).

(9) Remove second stage compressor blades (14) from disk (23) and place in suitablecontainer.

(10) Remove second stage compressor disk (23) using Puller (PWC30487).

(11) Remove second stage vane and shroud assembly (22) by prying off evenly.

(12) Remove second stage disk spacer (21) using Puller (PWC30422).

(13) Remove third stage compressor blades (19) from disk (20) and place in suitablecontainer.

(14) Remove third stage compressor disk (20) using Puller(PWC30487) .

(15) Remove third stage vane and shroud assembly (8) by prying off evenly.

(16) Remove third stage disk spacer (7) using Puller (PWC30422).

(17) Remove impeller housing (6).



Page 5-1-78May 23/2003

(18) Remove centrifugal impeller (3) from stand and place on bench with stubshaftfacing up.

(19) Remove rotor air seal (18) and No. 2 bearing inner race using Puller (PWC30489).

(20) Remove compressor front stubshaft (2) from impeller using Puller Rod(PWC30367) and Adapter Body (PWC30368). Remove preformed packing (13).

(21) Remove compressor rotor air seal (29) from compressor rear hub using Puller(PWC30108).

CAUTION: USE EXTREME CARE WHEN REMOVING BALANCE WEIGHT TOPREVENT DAMAGING RETAINING RING. GOUGES AND CRACKS ARENOT ACCEPTABLE AND ARE REASONS FOR REJECTION OF THE RING.

(22) Remove all balancing rivets and balance weights (10) and (11) from compressorrear hub. Retain balance weights.

(23) Remove counterweights balancing bolts and keywashers (15) from front stubshaftand discard bolts and keywashers.

42. NO. 2 BEARING FRONT STATOR AIR SEAL AND GAS GENERATOR CASE

A. Remove No. 2 bearing front stator air seal and gas generator case as follows:

(1) Remove bolts, cabin air outlet, blanking covers and gasket from gas generator case.

(2) Remove bolts and washers securing air inlet screen support ring to gas generatorcase. Remove ring.

(3) Remove eight bolts and withdraw front stubshaft stator air seal and spiral-woundgasket from rear of gas generator case.

(4) Rotate gas generator case on stand, with flange C face up.

(5) Remove eight double-hexagon bolts and withdraw No. 2 bearing cover.

(6) Remove eight hexagon bolts and withdraw stator air seal and spiral-wound gasketfrom front of gas generator case.

(7) Remove No. 2 bearing oil nozzle by pulling outward until it clears bearing flange,rotate nozzle 90 degrees counterclockwise and withdraw from case.

(8) Remove spring pin from rear end of nozzle and remove oil jet strainer .

(9) Unlock four keywashers, remove bolts and washers (17, Fig. 5-1-30) and withdrawouter race of No. 2 bearing (16) from gas generator case.

(10) Remove gas generator case from overhaul stand.



Page 5-1-79May 23/2003

2021

2223

2425

2627

28 29

1211

109

19

14

1817

1615

13

12

34 5

46

78

C1605

Compressor Rotor AssemblyFigure 5-1-30

(Post-SB1094) AND PT6A-20A ENGINES



Page 5-1-80May 23/2003

43. T5 THERMOCOUPLE HARNESS ASSEMBLY (Pre-SB1073 WITH Post-SB1246)

A. Remove T5 thermocouple harness assembly (Ref. Fig. 5-1-31 and 5-1-32):

(1) With sling installed on power section (Ref. Paragraph 30., preceding), locate powersection on Mount Ring (PWC30269) of Stand (PWC30800) and secure with nutsand bolts. Remove sling and rotate power section on stand until flange C is vertical.Lock stand in this position.

(2) SB1218: Remove interstage sealing rings (6, Fig. 5-1-31) from rear of statorhousing. Overlap and compress spring ends to clear retaining plates (9).

(3) Post-SB1246: Remove 10 bolts (23, Fig. 5-1-32) securing containment ring (22) toflange D. Allow ring to rest on flange.


1. Tie Rod2. Front Stubshaft3. Centrifugal Impeller4. Preformed Packing5. Compressor Breather Tube6. Impeller Housing7. Third Stage Disk Spacer8. Third Stage Vane and Shroud Assembly9. Nut and Keywasher

10. Rivet - Final Balancing11. Balance Weight and Rivet12. First Stage Compressor Blade13. Preformed Packing14. Second Stage Compressor Blade15. Bolt - Counterweight Balance and Keywasher16. No. 2 Bearing17. Bolt and Keywasher18. Rotor Air Seal19. Third Stage Compressor Blades20. Third Stage Compressor Disk21. Second Stage Disk Spacer22. Second Stage Vane and Shroud Assembly23. Second Stage Compressor Disk24. First Stage Disk Spacer25. First Stage Vane and Shroud Assembly26. Compressor Rear Hub Assembly27. Straight Pin28. Rear Hub Coupling29. Rear Rotor Air Seal



Page 5-1-81May 23/2003

3

4

91

7

10

DETAIL OF LOWER PROBE BOSSBLANKING PLUG (POST−SB1212)

11 9

1

2

3

4

5

6

7

8

C1606B

T5 Thermocouple Harness and ProbesFigure 5-1-31

Pre-SB1073 Engines



Page 5-1-82May 23/2003

(4) Post-SB1246: Exercising care to prevent excessive pressure being applied toharness and probes, move containment ring (22) sufficiently and remove lockwiresecuring harness leads to clips (8) and (9) on exhaust duct.

(5) Using Wrench (PWC30114-05), unscrew coupling nuts (1, Fig. 5-1-31) and removeT5 probes (7) from respective bosses on stator housing (2).

(6) Remove lockwire securing harness leads to clips on stator housing.

(7) Carefully remove harness assembly together with containment ring (22, Fig. 5-1-32).

(8) Place harness assembly in suitable container.

(9) SB1212: Remove two plugs (11) from redundant probe bosses at 6 o’clock positionon stator housing.

44. T5 THERMOCOUPLE HARNESS, BUS-BAR AND PROBES (Post-SB1073 AND ALLPT6A-20A ENGINES) WITH Post-SB1246

A. Remove thermocouple harness, bus-bar assembly and probes (Ref. Fig. 5-1-32):

(1) With sling installed on power section (Ref. Paragraph 30., preceding), locate powersection on Mount Ring (PWC30269), of Stand (PWC30800) and secure with nutsand bolts. Remove sling and rotate power section on stand until flange C is vertical.Lock stand in this position.

(2) Disconnect leads (6) and (12) from respective terminals on bus-bar assembly. Cutlacings and release leads from clips (4) and (10) on stator housing (13).

CAUTION: EXERCISE CARE WHEN REMOVING CAPSCREWS. DO NOT APPLYEXCESSIVE PRESSURE ON PROBE TERMINAL BARS, AS CERAMICINSULATION IS EXTREMELY FRAGILE.

(3) Using a 9/32-inch open end wrench, hold probe and remove capscrews (26,Pre-SB1503) or bolts (Post-SB1503) connecting bus-bar straps (19) to probes.


1. Retaining Nut2. Stator Housing3. T5 Harness4. Terminal Block5. Clips6. Interstage Sealing Ring(s)7. T5 Probe Assembly8. Exhaust Duct9. Sealing Retaining Plate

10. Spacer11. Blanking Plugs (Post-SB1212)



Page 5-1-83May 23/2003

30

DETAIL OF LOWER PROBEBOSS BLANKING PLUGS

24

25

26

2728

29

DETAIL OF TYPICALTHERMOCOUPLE PROBES 11

2

3

9

1

2322

21

45

20

19

18

17

16

1514 10 13

12

11

10

876

B

C6242

T5 Thermocouple Harness, Busbar and ProbesFigure 5-1-32

Post-SB1073 and all PT6A-20 Engines with Post-SB1246



Page 5-1-84May 23/2003

(a) Pre-SB1503: Use a 9/64-inch Allen wrench for capscrews at alumel terminal (25)and a 7/64-inch Allen wrench at chromel terminal (24).

(b) Post-SB1503: Use a 7/32-inch socket for bolts at alumel terminal (25). Use a3/16 inch socket for bolts at chromel terminal (24).

(4) Remove five screws (17) and seal ring retaining plates (18) ( Post-SB1102) andremove bus-bar assembly from stator housing (13).

(5) SB1218: Remove interstage sealing ring(s) (14).

(6) Using Wrench (PWC30114-08), unscrew coupling nuts (27) and remove probes (29)and washers (28) from respective bosses on stator housing.


1. Exhaust Duct2. T5 Terminal Block3. T5 Thermocouple Harness4. Clip5. Bolt6. Lon Lead7. Half Rings (Post-SB1246)8. Clip9. Clip

10. Clip11. Thermocouple Probe12. Short Lead13. Stator Housing14. Interstage Sealing Ring(s) (SB1218)15. Alumel Bus-bar16. Chromel Bus-bar17. Screws18. Retaining Plates (Post-SB1102)19. Bus-bar Straps20. Power Turbine Vane Ring21. Socket Head Screw22. Containment Ring (Post-SB1246)23. Bolt24. Chromel Terminal25. Alumel Terminal26. Capscrew27. Coupling Nut28. Copper Washer29. Thermocouple Probe30. Plug (Post-SB1212)



Page 5-1-85May 23/2003

(7) SB1212: Remove two plugs (30) from redundant probe bosses at 6 o’clock positionon stator housing.

(8) Post-SB1246: Remove containment ring (22) from flange D by removing 10 bolts(23). Exercise care not to chafe harness when removing ring.

(9) Cut lacings and remove harness (3) from clips (8) and (9) on exhaust duct (1).

45. POWER TURBINE INTERSTAGE BAFFLE AND VANES (Pre-SB1061)

A. Remove power turbine interstage baffle and power turbine vanes (See Fig. 5-1-33):

(1) With power section mounted in overhaul stand, rotate power section until flange Cis vertical, lock stand in this position.

(2) Remove stator housing attachment parts as follows:

(a) Pre-SB1246: Remove 12 bolts (12) securing housing to flange D of exhaustduct (1).

(b) Post-SB1246: Remove two bolts (5, Fig. 5-1-32) at 1 and 7 o’clock positionson flange D and remove upper and lower half ring (7) from front face of flange.

CAUTION: USE CARE DURING REMOVAL TO PREVENT TURBINE VANES (11)FALLING FREE OF STATOR HOUSING AND CAUSING POSSIBLEDAMAGE.

(3) Withdraw assembly and place on bench with leading edge of vanes face up.

(4) Remove stator housing assembly (14) from interstage baffle assembly (10) andfront air seal (13).

(5) Remove power turbine vanes (11), sealing strip (5), sealing strip cover (6) andpacking (7) from interstage baffle assembly. Place vanes in suitable containers.

(6) Remove two packings (8) and (9) from interstage baffle inner platform.

(7) Pre-SB1246: Back off exhaust duct flange reinforcing ring halves (3) and (17) fromflange D; remove headed pins (2) from ring clevis and remove ring halves.

46. TURBINE INTERSTAGE STATOR HOUSING AND POWER TURBINE VANE RING(Post-SB1061 AND PT6A-20A ENGINES)

A. Remove turbine interstage stator housing and power turbine vane ring from powersection (Ref. Fig. 5-1-33):

(1) Remove 12 bolts (12) securing stator housing (14) to exhaust duct (1) at flange D.Withdraw stator housing and power turbine shroud assembly (15) by pulling onvanes.

(2) Place stator housing and power turbine shroud assembly on bench with leadingedge of vanes up, then lift stator housing from power turbine shroud assembly.



Page 5-1-86May 23/2003

(3) Back off exhaust duct flange reinforcing ring halves (3) and (17) from flange D;remove headed pins (2) from ring clevis and remove ring halves.

47. POWER TURBINE ASSEMBLY AND SHROUD (Pre-SB1046)

A. Remove power turbine assembly and shroud (Ref. Fig. 5-1-34):

(1) Unlock tabwasher (3) and remove five nuts (4), tabwasher and rotor air seal (5).

(2) Remove power turbine disk (7) and blades from power turbine shaft using Puller(PWC30310).

(3) Using an approved marking method (Ref. Part 3), index-mark power turbine shroudring with respect to offset hole on exhaust duct; this action will ensure correctlocation if same shroud is reinstalled.

(4) Install Puller (PWC30139) and remove power turbine shroud (6) from exhaust ductassembly (1), rotating puller 90 degrees to ensure even removal of shroud.

48. POWER TURBINE ASSEMBLY AND SHROUD RING (Post-SB1046 AND PT6A-20AENGINES)

A. Remove power turbine disk and blade assembly as follows (Ref. Fig. 5-1-35):

(1) Install Wrench (PWC30332) at flange D of exhaust duct ensuring that dogs arecorrectly seated to prevent power turbine disk rotating.

(2) Install teflon Protector Sleeve (PWC30336) in centerbore of power turbine disk.

(3) Install Unlocking Tool (PWC30335) in centerbore of power turbine disk and unlockcenter bolt keywasher.

(4) Remove unlocking tool and break torque on mounting bolt using conventionalsocket. Remove bolt and keywasher.

(5) Remove protector from turbine disk centerbore and wrench from flange D. InstallPuller (PWC30403) (1) in centerbore of power turbine disk and remove disk andblade assembly from power section. Place assembly on bench and remove puller.

(6) Using an approved marking method (Ref. Part 3), index-mark power turbine shroudring with respect to the off set hole on exhaust duct; this action will ensure correctlocation if same shroud is reinstalled.

(7) Using Puller (PWC30139), withdraw power turbine shroud ring from exhaust duct,rotating puller 90 degrees to ensure even removal of shroud ring.

49. POWER TURBINE BLADES

A. Remove blades from power turbine assembly (See Fig. 5-1-36 and 5-1-25):

NOTE: Before removing blades (3, Fig. 5-1-36), inspect both sides of disk assembly(2) for blade shift. If shift has occurred on one or more blades, measure andrecord amount of shift for reference at subsequent inspection.



Page 5-1-87May 23/2003

17CFLANGE

DFLANGE

1615

14

POST−SB1061

12

13

1 2 3

4 5 67

8

9

10

11PRE−SB1061

C1607A

Power Turbine Vanes, Shroud and Exhaust DuctFigure 5-1-33



Page 5-1-88May 23/2003

CAUTION: THIS PROCEDURE APPLIES TO DISKS WITH TUBULAR BLADERETAINING RIVETS ONLY.

(1) Prepare blade retaining Rivet Drilling Fixture (PWC38296) as follows (Ref. Fig.5-1-25):

(a) Install Drill Bit (1) (PWC38293) in chuck (2).

NOTE: Using drill gage (17) on column (18), ensure diameter of drill bitselected is required size.

(b) Connect compressed air supply to inlet of pedal valve (19).

(c) Depress foot pedal and gradually open air regulator valve (3) until air pressurereads 20 psig on gage (4).

(d) Assemble disk (10) to Disk Support (8) (PWC32252). Secure with pad (23) andknurled nut (7).

(e) Install disk (10)/disk support (8) assembly in cradle (20), and secure with screw(6).

NOTE: If necessary, release screw (5) and rotate cradle (20) sufficiently togain access to screw (6). Tighten screw (5).

(f) Release screw (5) and allow cradle (20) to settle at zero degree position onprotractor (9).


1. Exhaust Duct2. Head Pin3. Flange Reinforcing Ring - Upper Half (Pre-SB1246)4. Power Turbine Shroud5. Sealing Strip6. Sealing Strip Cover7. Packing - Vane8. Packing - Vane Inner Platform9. Packing - Vane Inner Platform

10. Interstage Baffle Assembly11. Turbine Vane12. Double-hexagon Bolt13. Interstage Front Air Seal14. Power Turbine Stator Housing Assembly15. Power Turbine Shroud Assembly (Post-SB1061 and all

PT6A-20A Engines)16. Power Turbine Shroud (Post-SB1061 and all PT6A-20A

Engines)17. Flange Reinforcing Ring - Lower Half (Pre-SB1246)



Page 5-1-89May 23/2003

3

21

4

5

6

7

8

C41508

Power Turbine AssemblyFigure 5-1-34

Pre-SB1046



Page 5-1-90May 23/2003

(g) Position cradle (20) at an angle of minus 20 degrees as indicated onprotractor (9). Tighten screw (5).

NOTE: When facing protractor, negative angle is obtained by rotating cradleto the right of fixed zero degree, positive angle to the left (Ref. Fig.5-1-25, View C).

CAUTION: RIVET AND DRILL MUST BE CENTRALIZED TO ENSURE DAMAGETO DISK DOES NOT OCCUR.

(h) Release screw (11), and slide assembly to bring rivet under drill bit (1).Centralize rivet by rotating disk and sliding assembly laterally until drill bit iscorrectly aligned in rivet hole. Tighten screw (11).

(2) Set drill cutting depth as follows (Ref. Fig. 5-1-25, View A):

(a) Loosen knob (12) if necessary, and move gage (13) away from rod (14).

(b) Using lever (21), position drill bit (1) to contact centralized flared rivet headand, holding drill in position, slide gage (13) to contact rod (14).

(c) Turn nut (15) to just make contact with gage (13).

(d) Slide gage (13) away from rod (14), release lever (21), and tighten nut (16) tolock nut (15) in position.

(e) Secure gage (13) in position away from rod (14) with knob (12).

(f) With drill retracted, depress pedal valve (19). Ensure drill is rotating and pistonbrake (22) is functioning (disk cannot rotate). Release pedal valve.

(3) Drill rivets as follows:

WARNING: WEAR PROTECTIVE EYE GOGGLES WHEN DRILLING RIVETHEADS.

(a) Apply one drop of engine oil to each flared rivet head.

(b) Ensure rivet is centralized (Ref. Para. A., Step (1) (h), preceding).


1. Exhaust Duct2. Flange D3. Tabwasher4. Nuts5. Rotor Air Seal6. Power Turbine Shroud7. Turbine Disk8. Exhaust Case Drain Valve (Pre-SB1040)

Exhaust Case Drain Plug (Post-SB1040)



Page 5-1-91May 23/2003

3 1

2

C671A

Power Turbine AssemblyFigure 5-1-35



Page 5-1-92May 23/2003

(c) With drill retracted, depress pedal valve (19). Drill rivet, retract drill andrelease pedal valve.

(d) Repeat Steps (b) and (c) until all rivets are drilled.

(e) Loosen screw (6), and remove disk (10)/disk support (8) assembly from cradle(20). Install assembly on Base (PWC38288).

(4) Shear rivets and remove turbine blades as follows:

CAUTION: USE EXTREME CARE DURING RIVET REMOVAL TO AVOIDMARKING OR OTHERWISE DAMAGING DISK.

(a) Using Rivet Punch (PWC38297) and suitable hammer, tap on drilled rivet headuntil flare shears. Remove rivet.

(b) Repeat Step (a) until all rivets are removed.

(c) Remove blades from disk collectively by tapping fir tree roots lightly withsuitable fiber drift, working progressively around disk. Use penetrating oil ifnecessary to facilitate blade removal.

NOTE: Interlocked shrouded blades cannot be removed individually.

(d) Place blades (3, Fig. 5-1-36) in separate containers, preferably with individualcompartments, to ensure blades receive adequate protection during overhaul.

(e) Remove disk (10, Fig. 5-1-25)/disk support (8) assembly from Base(PWC38288); disassemble knurled nut (7) and pad (23); and remove disk (10)from disk support (8).

B. Remove balance weights, retaining rivets and balance rivets (Ref. Fig. 5-1-36):

(1) Place disk on suitable wood or fiber supports.

(2) Remove balance weights, retaining rivets and balance rivets from disk rim byremoving outer heads of rivets with flat chisel, then punching out stems with0.062 inch diameter drift.

(3) Place disk in container for protection against possible damage during overhaul.


1. Puller (PWC30403)2. No. 3 Bearing Cover (Pre-SB1171 Engines)

No. 3 Bearing Cover/Spacer Assembly (Post-SB1171 andPT6A-20A Engines)

3. Power Turbine Shroud Ring



Page 5-1-93May 23/2003

VIEW A

A

8

2

13

4

56

7

C8447

Power Turbine Blades RemovalFigure 5-1-36



Page 5-1-94May 23/2003

50. REDUCTION GEARBOX

A. Remove reduction gearbox from exhaust duct (Ref. Figs. 5-1-34, 5-1-35, 5-1-37, and5-1-38):

(1) On Pre-SB1171 engines, remove retaining ring, No. 3 bearing cover spacer andNo. 3 bearing cover (2, Ref. Fig. 5-1-35) from rear of power turbine shafthousing.

(2) On Post-SB1171 and PT6A-20A engines, remove retaining ring and No. 3 bearingcover assembly (2) from rear of power turbine shaft housing.

(3) Rotate power section in overhaul stand until propeller shaft flange is facing up.Lock stand in this position.

(4) Remove self-locking nuts, washers and bolts from flange A, and remove enginefront lifting bracket.

(5) Install one Jackscrew (PWC30226) (4, Fig. 5-1-37) in each of four jacking insertsin flange A (5). Tighten jackscrews to separate front and rear cases of reductiongearbox.

(6) Attach Lifting Eye (PWC30040) (1) or Sling (PWC30037) to flange of propeller shaft(2). Lift gearbox (3) and transfer to bench. Remove lifting eye or sling, invertgearbox and mount on Base (PWC30322).

(7) Remove all oil transfer tubes and jackscrews. Remove preformed packings fromtubes and from groove in flange A.

(8) Lift rear case of reduction gearbox (1, Fig. 5-1-38) complete with power turbineshaft housing from exhaust duct (3). Place assembly on bench with flange Afacing down.

(9) Pre-SB1089: Remove two halves of insulation blanket (2) from exhaust duct innercore.

(10) Post-SB1089 and PT6A-20A: Remove single-piece insulation blanket (2) fromexhaust duct inner core.


1. Punch2. Power Turbine Disk3. Power Turbine Blade4. Balance Rivet5. Balance Weight6. Weight Retaining Rivet7. Balancing Rim8. Blade Retaining Rivet



Page 5-1-95May 23/2003

1

2

3

4

5

C682C

Reduction Gearbox Front CaseFigure 5-1-37



Page 5-1-96May 23/2003

(11) Pre-SB1040: Unlock keywasher and remove drain valve stop and keywasher fromexhaust duct. Remove drain valve (8, Fig. 5-1-34) and spring from housing.

(12) Post-SB1040: Drain valve has been replaced by a drilled plug permanently stakedin position on exhaust duct. Do not remove plug.

(13) Remove nuts and bolts securing exhaust duct to overhaul stand mount ring.Remove exhaust duct.

51. POWER TURBINE SHAFT AND SHAFT HOUSING (Pre-SB1046)

A. Remove and Disassemble Power Turbine Shaft and Shaft Housing (Ref. Fig. 5-1-39):

(1) Remove five bolts (14) securing heat shield to stator air seal (15). Withdraw heatshield from shaft housing assembly (23).

(2) Remove 12 self-locking nuts (24) securing shaft housing to rear case of reductiongearbox at flange B.

(3) Separate shaft housing from rear case by lightly tapping with a soft-faced hammer.

(4) Remove transfer tubes (27) and (36) from shaft housing or from rear case.Remove preformed packings (26), (35) and (34).

(5) Remove oil filter (25) from oil pressure tube in shaft housing.

(6) Install assembly of power turbine shaft and housing on Assembly Base (PWC30090).Secure shaft to base with bolts and nuts.

(7) Remove retaining ring (2) from outer groove in shaft coupling (6). Remove sun gear(1) and retaining ring (3) from inner groove in shaft coupling.

(8) Unlock cupwasher (5) and remove spanner nut (4) and cupwasher securing shaftcoupling to power turbine shaft using Socket (PWC30088).

(9) Remove shaft coupling and positioning ring (7) from power turbine shaft.

(10) Remove No. 4 bearing front split inner race using Puller (PWC30085).

(11) Insert Retainer (PWC30132) into No. 4 bearing location and remove shaft housingassembly from power turbine shaft, leaving shaft on base.

(12) Remove No. 4 bearing balls and cage from outer race at rear of shaft housing.


1. Lifting Eye(PWC30040) or Sling (PWC30037)2. Propeller Shaft Flange3. Reduction Gearbox Front Case4. Jackscrew (PWC30226)5. Flange A



Page 5-1-97May 23/2003

1

2

5

4

3

C681A

Removal of Rear Case of Reduction Gearbox from Exhaust DuctFigure 5-1-38



Page 5-1-98May 23/2003

(13) Unlock keywashers (19) and remove nuts, keywashers and D-head bolts (16)securing flanged outer race of No. 4 bearing (8) to shaft housing. Withdraw outerrace.

(14) Unlock keywasher (10) and remove external thread spanner nut (9) and keywasherusing Socket (PWC30091 ) and Wrench (PWC30218), and remove No. 3 bearingouter race (13) from shaft housing.

(15) Unlock keywasher (21) and remove No. 3 bearing fluid passage bolt (22),keywasher and oil nozzle assembly (20) from oil pressure tube rear boss.

(16) Unlock keywasher (30) and remove No. 3 bearing oil nozzle (29) and keywasherfrom oil pressure tube front boss.

(17) Remove No. 4 bearing rear split inner race from power turbine shaft using Puller(PWC30085).

(18) Unlock keywasher (12) and remove spanner nut (11) and keywasher securing No. 3bearing inner race using Socket (PWC30089).

(19) Remove No. 3 bearing inner race and rollers together with oil slinger (18) usingPuller (PWC30082).

(20) Remove spiral-wound gasket (17) and stator air seal (15).

(21) Remove rotor air seal (33) from power turbine shaft (28) using Puller (PWC30082).

(22) Remove power turbine shaft from assembly base and withdraw disk mountingbolts (32).

(23) Remove power turbine rear rotor air seal (31) using Puller (PWC30082) andAdapter (PWC30125).

52. POWER TURBINE SHAFT AND SHAFT HOUSING (Post-SB1046 and Pre-SB1057)

A. Remove and disassemble power turbine shaft and shaft housing (See Fig. 5-1-40):

(1) Remove five bolts (35) securing heat shield to stator air seal (34). Withdraw heatshield from shaft housing assembly (19).

(2) Remove 12 self-locking nuts (18) securing shaft housing to rear case of reductiongearbox at flange B.

(3) Separate shaft housing from rear case by lightly tapping with soft-faced hammer.


1. Reduction Gearbox Rear Case2. Insulation Blanket3. Exhaust Duct4. Mount Ring (PWC30269)5. Exhaust Duct (Flange C)



Page 5-1-99May 23/2003

35 3635

34

3332

30

29

3128

FWD 26

2527 26

2423

1415

1718

202122

16

19

12 3 4 5

6

78

9 10 11 12 13

C1608

Power Turbine Shaft and Shaft HousingFigure 5-1-39

Pre-SB1046



Page 5-1-100May 23/2003


1. Sun Gear2. Retaining Ring3. Retaining Ring4. Spanner Nut5. Cupwasher6. Power Turbine Shaft Coupling7. Positioning Ring8. No. 4 Flanged Bearing9. Spanner Nut

10. Keywasher11. Spanner Nut12. Keywasher13. No. 3 Roller Bearing14. Bolt15. Stator Labyrinth Air Seal16. D-head Bolt17. Spiral-wound Gasket18. Oil Slinger19. Keywasher and Nut20. Oil Nozzle Assembly21. Keywasher22. Bolt - Fluid Passage23. Shaft Housing Assembly24. Self-locking Nut25. Oil Filter26. Preformed Packing27. Transfer Tube28. Power Turbine Shaft29. Oil Nozzle30. Keywasher31. Rotor Air Seal - Rear32. D-head Bolt33. Rotor Air Seal - Front34. Preformed Packing35. Preformed Packing36. Transfer Tube



Page 5-1-101May 23/2003

29

28

2726

25

3031

3233

34

2423

35

2021

22

1415

16 17 18 19

1 2 3 4 56

7 8 9 10 11

13

12

C1609A

Power Turbine Shaft and Shaft HousingFigure 5-1-40

Post-SB1046 and Pre-SB1057



Page 5-1-102May 23/2003


1. Sun Gear2. Retaining Ring3. Retaining Ring4. Spanner Nut5. Cupwasher6. Shaft Coupling7. Positioning Ring8. No. 4 Flanged Ball Bearing9. Spanner Nut

10. Keywasher11. No. 3 Bearing Outer Race12. D-head Bolt13. Keywasher and Nut14. Preformed Packing15. Transfer Tube16. Preformed Packing17. Oil Filter18. Self-locking Nut19. Power Turbine Shaft Housing Assembly20. Bolt - Fluid Passage21. Keywasher22. Oil Nozzle Assembly23. Oil Nozzle24. Keywasher25. Preformed Packing26. Transfer Tube27. Preformed Packing28. Preformed Packing29. Power Turbine Shaft30. Spacer31. No. 3 Bearing Inner Race and Roller Assembly32. Rotor Air Seal33. Spiral Wound Gasket34. Stator Air Seal35. Double-Hexagon Bolt



Page 5-1-103May 23/2003

(4) Remove transfer tubes (15) and (26) from shaft housing or from rear case. Removepreformed packings (14), (16), (25), (27) and (28).

(5) Remove oil filter (17) from oil pressure tube in shaft housing.

(6) Install assembly of power turbine shaft and housing on Fixture (PWC30560).

(7) Remove retaining ring (2) from outer groove in shaft coupling (6). Remove sun gear(1) and retaining ring (3) from inner groove in shaft coupling.

(8) Unlock cupwasher (5) and remove spanner nut (4) and cupwasher securing shaftcoupling to power turbine shaft (29), using Socket (PWC30384).


(10) Remove No.4 bearing front split inner race using Puller (PWC30473).

(11) Insert bearing Retainer (PWC30132) into No.4 bearing location and remove shafthousing assembly from power turbine shaft, leaving shaft on fixture.

(12) Remove No. 4 bearing balls and cage from outer race at rear of shaft housing.

(13) Unlock keywashers (13) and remove nuts, keywashers and D-head bolts (12)securing flanged outer race of No. 4 bearing (8) to shaft housing.

(14) Remove outer race from housing.

(15) Unlock keywasher (10), and remove external thread spanner nut (9) and keywasherusing Socket (PWC30091) and Wrench (PWC30218). Remove outer race (11) fromshaft housing.

(16) Unlock keywasher (21) and remove No. 3 bearing fluid passage bolt (20),keywasher and oil nozzle assembly (22) from oil pressure tube rear boss.

(17) Unlock keywasher (24) and remove No. 3 bearing oil nozzle (23) and keywasherfrom oil pressure tube front boss.

(18) Remove No. 4 bearing rear split inner race using Puller (PWC30473).

(19) Invert power turbine shaft (29) on fixture.

(20) Remove spiral-wound gasket (33) and stator air seal (34).

(21) Remove rotor air seal (32) and No. 3 bearing inner race and roller assembly (31)from shaft using Puller (PWC30489).

(22) Remove No. 3 bearing spacer (30) (if fitted) from shaft.

(23) Remove shaft from fixture.



Page 5-1-104May 23/2003

53. POWER TURBINE SHAFT HOUSING (Post-SB1057 AND Pre-SB1089 ENGINES)

A. Remove and disassemble power turbine shaft housing (See Fig. 5-1-41):

(1) Remove retaining ring (27) securing heat shield (28) at rear of shaft housingassembly (14). On Post-SB1287 cover assemblies, care should be taken not todamage anti-rotation dimples during removal of No. 3 bearing cover assembly.

(2) Withdraw heat shield from shaft housing assembly.

(3) Remove 12 self-locking nuts (25) securing shaft housing assembly to rear case ofreduction gearbox at flange B.

(4) Separate shaft housing from rear case. Remove transfer tube (20) from rear case,or shaft housing (as applicable), and remove preformed packings (21).

NOTE: On Post-SB1057 and Post-SB1138 engines, remove shaft housing sleeve(31) (with housing) as an assembly.


(6) Remove retaining ring (2) securing sun gear (1) in shaft coupling (6). Remove sungear and retaining ring (3) from shaft coupling.



(9) Remove No. 4 bearing front split inner race (8) using Puller (PWC30473).

(10) Unlock keywashers and remove bolts and keywashers securing No. 4 bearing outerrace (10) to bearing mounting flange (15) in shaft housing. Remove bearing outerrace complete with balls and cage (9).

(11) Remove power turbine shaft assembly from housing.

(12) Remove No. 3 bearing scavenge oil tube assembly (23) from shaft housing.Remove preformed packing (22).

(13) Remove No. 3 bearing oil pressure tube (18) from shaft housing and remove oil jetstrainer (19) from tube.

(14) Unlock keywashers (26) and remove bolts, keywashers and No. 3 bearing outerrace (13) from bearing mounting flange (12) in shaft housing.

54. POWER TURBINE SHAFT HOUSING (Post-SB1089 and PT6A-20A ENGINES)

A. Remove and disassemble power turbine shaft housing (See Fig. 5-1-41):

(1) Remove 12 self-locking nuts (25) securing shaft housing assembly to rear case ofreduction gearbox at flange B.



Page 5-1-105May 23/2003

3029

28

27

14

31

2526

23

2217

1312

15

11

2120

2119

18

16

24

12

34

5

6

78

9

10

FWD

C1610

Power Turbine Shaft HousingFigure 5-1-41

(Post-SB1057 and SB1089 and all PT6A-20A Engines)



Page 5-1-106May 23/2003

(2) Separate shaft housing from rear case.

NOTE: On Post-SB1138 engines, remove shaft housing sleeve (31) with shafthousing.


(4) Remove retaining ring (2) securing sun gear (1) in shaft coupling (6). Remove sungear and retaining ring (3) from shaft coupling.



1. Sun Gear2. Retaining Ring3. Retaining Ring4. Spanner Nut5. Cupwasher6. Shaft Coupling7. Coupling Positioning Ring8. No. 4 Bearing Front Split Inner Race9. No. 4 Bearing Balls and Cage

10. No. 4 Bearing Outer Race11. No. 4 Bearing Rear Split Inner Race12. No. 3 Bearing Outer Race14. Shaft Housing Assembly15. No. 4 Bearing Mounting Flange16. No. 3 Bearing Inner Race and Rollers17. Power Turbine Shaft18. No. 3 Bearing Oil Pressure Tube Assembly19. Oil Jet Strainer20. Transfer Tube21. Preformed Packing22. preformed Packing23. No. 3 Bearing Scavenge Oil Tube Assembly24. Rotor Air Seal25. Self-locking Nut26. Bolt and Keywasher27. Retaining Ring28. Heat Shield29. Retaining Ring30. Stator Air Seal31. Shaft Housing Sleeve



Page 5-1-107May 23/2003

(6) Remove shaft coupling and positioning ring (7) from shaft.

(7) Remove No. 4 bearing front split inner race (8) from shaft using Puller (PWC30473).

(8) Unlock keywashers and remove bolts and keywashers securing No. 4 bearingouter race (10) to bearing mounting flange (15) in shaft housing.

(9) Remove shaft housing from shaft assembly.

(10) Remove No. 3 bearing scavenge oil tube assembly (23) from shaft housing.Remove preformed packing (22).

(11) Remove No. 3 bearing oil pressure tube (18) from shaft housing and remove oil jetstrainer (19) from tube.

(12) Unlock keywashers (26) and remove bolts, keywashers and No. 3 bearing outerrace (13) from bearing mounting flange (12) in shaft housing.

NOTE: Because of the relatively tight fit involved, the No. 3 bearing stator air seal(30), installed at rear of shaft housing and retained by ring (29), should notbe removed at disassembly. If removal is required, refer to Part 8.

(13) Invert power turbine shaft assembly on fixture with No. 4 bearing facing up.

55. POWER TURBINE SHAFT

A. Disassemble power turbine shaft (See Fig. 5-1-41):

(1) Using Puller (PWC30473), remove No.4 bearing rear split inner race (11) frompower turbine shaft (17).

(2) Invert power turbine shaft on Fixture (PWC30560).

(3) Using Puller (PWC30489), remove No. 3 bearing inner race and roller assembly(16) and rotor air seal (24) from power turbine shaft.

(4) Remove turbine shaft from fixture.

56. REDUCTION GEARBOX REAR CASE

A. Disassemble reduction gearbox rear case (See Fig. 5-1-42):

(1) With rear case (37) flange A face down on bench, remove first stage carrier thrustwasher (38) and retaining ring (39) from rear of planet gear carrier (25) or (12)using Puller (PWC30353).

(2) Remove thrust washer, retaining ring and dowel pin (40).

(3) Lift rear case from first stage planet gear carrier. Install case on Support Plate(PWC30225).

(4) Remove six bolts (24) and retaining plates (23) securing first stage reduction ringgear (22) to rear case. Remove ring gear.



Page 5-1-108May 23/2003

(5) Remove torquemeter piston (21), seal rings (20), torquemeter valve (35), and valvespring (36) from rear case recess.

(6) Unlock keywashers (33) and remove eight bolts (32) and keywashers (33) securingtorquemeter cylinder (34) to rear case. Remove cylinder using fiber drift.

(7) Remove rear case from support plate.

57. FIRST STAGE REDUCTION PLANET GEAR CARRIER (Pre-SB1124)

A. Disassemble first-stage reduction planet gear carrier (See Fig. 5-1-42):

(1) Install planet gear carrier (25) on Assembly Fixture (PWC30057).

(2) Unlock keywasher (30) and remove spanner nut (31) and keywasher securingsecond stage sun gear (27) to carrier using Socket (PWC30061).

(3) Remove splined adapter (29) flexible coupling (28), second-stage sun gear (27) andspacer (26), as applicable.

(4) Unlock keywasher (14), and remove planet gearpin screws (13) and keywashers.

(5) Remove first-stage planet gear carrier (25) from holding fixture.

(6) Remove planet gearpin assemblies (18)and remove first stage planet gears (15),sleeve bearings (16) and gearshafts (17) from carrier.

58. FIRST STAGE REDUCTION PLANET GEAR CARRIER (Post-SB1124 and PT6A-20AEngines)

A. Disassemble first-stage reduction planet gear carrier (See Fig. 5-1-42):

(1) Install planet gear carrier (12) on Assembly Fixture (PWC30057).

(2) Unlock keywasher (2) and remove spanner nut (1) and keywasher securingsecond-stage sun gear (9) to carrier, using Socket (PWC30061).

(3) Remove splined adapter (4), flexible coupling (7), second-stage sun gear (9) andsun gear stop (45) (Post-SB1367), as an assembly.

(4) Remove retaining rings (3), (5), (6), (8), and (46) (Post-SB1367). Separate splinedadapter, flexible coupling and second-stage sun gear stop (Post-SB1367). Discardretaining rings (3) and (5).

(5) Unlock keywashers (14) and remove planet gearpin screws (13) and keywashers.Remove oil seals (44) (Post-SB1397) from counterbores of gearpin screws.

(6) Remove planet gearpin assemblies and remove first-stage planet gears (15), sleevebearings (16), and gearshafts (17) from planet gear carrier. Using Puller(PWC30128-6), extract oil separator (41) (Pre-SB1397) or oil strainer (41)(Post-SB1397) and preformed packing (42) from gearpin. Discard preformed packingand Woodruff Key (43) (Post-SB1397).



Page 5-1-109May 23/2003

35 36 37 38 39

3233

3431 30 29

2827

2625

40

7 8 945 46

A

B

A CONFIGURATION

CONFIGURATION

1 2 3 4 5 6

10 11 12

A

DETAIL A

24 23 22 21 2013 14 15 16 17

4142 18

19

43

44

POST−SB1263PRE−SB1397

POST−SB1397

C13629

Reduction Gearbox Rear Housing ComponentsFigure 5-1-42



Page 5-1-110May 23/2003


1. Spanner Nut2. Keywasher3. Retaining Ring4. Splined Adapter5. Retaining Ring6. Retaining Ring7. Flexible Coupling8. Retaining Ring9. Second-stage Sun Gear

10. Preformed Packing11. Oil Restrictor12. Planet Gear Carrier (Pre-SB1124)13. Planet Gearpin Screw14. Keywasher15. Planet Gear16. Sleeve Bearing17. Planet Gearshaft18. Planet Gearpin19. Lockpin (Pre-SB1397)20. Seal Rings21. Torquemeter Piston22. First-stage Reduction Ring Gear23. Retaining Plate24. Bolt

25. Planet Gear Carrier (Post-SB1124)

26. Sun Gear Spacer27. Second-stage Sun Gear28. Flexible Coupling29. Splined Adapter30. Keywasher31. Spanner Nut32. Bolt33. Keywasher34. Torquemeter Cylinder35. Torquemeter Valve36. Valve Spring37. Reduction Gearbox Rear Case38. First-stage Carrier Thrust Washer39. Retaining Ring40. Dowel Pin41. Oil Separator (Pre-SB1397) or Oil

Strainer (Post-SB1397)42. Preformed Packing43. Woodruff Key (Post-SB1397)44. Oil Seal (Post-SB1397)45. Sun Gear Stop (Post-SB1397)46. Retaining Ring (Post-SB1397)



Page 5-1-111May 23/2003

(7) Remove first stage reduction oil restrictors (11) using a slave 0.190-32 bolt.Remove preformed packings (10) and discard.

(8) Remove first-stage reduction planet gear carrier from assembly fixture.

59. REDUCTION GEARBOX FRONT CASE (Pre-SB1124)

A. With front case of reduction gearbox mounted on Base (PWC30322), disassemble frontcase (See Fig. 5-1-43, 5-1-44 and 5-1-45):

(1) Remove retaining ring (15, Fig. 5-1-43) securing assembly of oil transfer tube (2)and No. 4 bearing oil nozzle (4) in propeller shaft (14), and release assembly intobore of shaft using Drift (PWC30066).

(2) Unlock keywasher (9, Fig. 5-1-44) and remove nut (8) and keywasher securingsecond-stage planet gear carrier (10) to propeller shaft, using Socket (PWC30324).

(3) Withdraw gear carrier assembly from propeller shaft using Puller (PWC30127) andinstall assembly on Holding Fixture (PWC30131).

(4) Install Bearing Retainer (PWC30062) on propeller shaft to prevent second-stagecarrier bearing (11) rollers spilling into front case.

(5) Unlock keywashers (21) and remove bolts (22), keywashers and retaining plates (6)securing second-stage reduction ring gear (7) to front case. Remove ring gear.

(6) Remove eight self-locking nuts (32, Fig. 5-1-43) and plain washers (31) securingthrust bearing cover (30) and flanged ball bearing (25) to front case.

(7) Remove bolts (12, Fig. 5-1-45) and plain washers (11) securing transfer tubelocating cover (10) to front case (5). Remove cover and preformed packing (9).

(8) Withdraw oil transfer tube (8) from front case using Puller (PWC30128-02). Removepreformed packings (6) and packing retainers (7) from tube.

(9) Pre-SB1223: Remove bolts (15) and plain washers (16) securing packing cover(17) and flanged oil transfer tube (19) to front case. Remove cover and preformedpacking (18). Withdraw flanged oil transfer tube from front case using Puller(PWC30128-01). Remove preformed packings (20 and 21).

(10) Post-SB1223: Remove bolts (15) and plain washers (16) securing flanged oiltransfer tube (19) to front case. Withdraw flanged oil transfer tube from frontcase using Puller (PWC30128-01). Remove preformed packings (20) and (21).

(11) Remove bolt (24) and plain washer (25) securing scavenge oil strainer plug (26) tofront case. Remove plug, preformed packing (27) and strainer (28) from front case.

(12) Remove two bolts (31) securing torquemeter pressure tapping connector (32) tofront case. Remove connector and preformed packing (33).

(13) Remove preformed packing (4) from transmitter boss on front case.

(14) Remove oil strainer (13) from cored passage at rear of front case.



Page 5-1-112May 23/2003

(15) Remove self-locking nuts (2) and plain washers (1) securing propeller governormounting gasket (3) and overspeed governor gasket (14) to respective mountingpads, and remove gaskets.

(16) Pre-SB1217: Remove drain plug (22) and preformed packing (23).

(17) Post-SB1217: Remove chip detector cover, chip detector (22) and preformedpacking (23).

(18) Remove self-locking nuts (39) and plain washers (38) securing power turbinegovernor and tachometer gasket (37) to front case, and remove gasket.

(19) Remove seal carrier (36) from front case using Puller (PWC30046-51). Removepreformed packing (35) from carrier. Remove seal (34).

CAUTION: DO NOT ROTATE FRONT CASE DURING FOLLOWING STEP. DAMAGECOULD RESULT IF THE BEVEL GEARSHAFTS (45 AND 51, Fig. 5-1-43)CONTACT OIL TRANSFER HOUSING (16).

(20) Carefully lift front case from propeller shaft by tapping with a fiber drift. Place caseon bench with flange A facing up.

(21) Unlock keywashers (23, Fig. 5-1-44) and remove bolts (24) and keywasherssecuring flanged roller bearing (11) to front case.

(22) Remove bearing retainer from propeller shaft. Install Puller (PWC30063), andremove bearing from front case.

(23) Remove oil transfer gallery (30, Fig. 5-1-45) from case using a fiber drift. Removepreformed packings (29).

(24) Disassemble propeller shaft as detailed in Para. 61.following.

60. REDUCTION GEARBOX FRONT CASE (Post-SB1124 AND PT6A-20A ENGINES)

A. With reduction gearbox front case mounted on Base (PWC30322) disassemble front case(Ref. Fig. 5-1-43, 5-1-44 and 5-1-45):

(1) Remove retaining ring (15, Fig. 5-1-43) securing assembly of oil transfer tube (11)and No. 4 bearing oil nozzle (9) in propeller shaft (14), and push assembly intobore of shaft using Drift (PWC30515).

(2) Unlock keywasher (9, Fig. 5-1-44) and remove plain nut (8) and keywashersecuring second stage planet gear carrier (25) to propeller shaft using Socket(PWC30324).

(3) Withdraw gear carrier assembly from propeller shaft using Puller (PWC30127) andinstall assembly on Holding Fixture (PWC30131).

(4) Install Bearing Retainer (PWC30062) on propeller shaft to prevent second stagecarrier bearing (11) rollers from spilling into front case.



Page 5-1-113May 23/2003

1455 15

47

48

49

50

51

47

46

45

DETAIL A

A

37 38 37

3940

PRE−SB1223

29

28 27 28 26 25 24 2322 21 20

19 18

1716

PRE−SB1223

41 42 43 44

PRE−SB122358

57

56

FCONFIGURATION

3334

3553

54

36

52

ECONFIGURATION

12 3 4 5

B CONFIGURATION

6 7 89 10 11

12

13

C CONFIGURATION

303132

POST−SB1137

33 34 59

30DCONFIGURATION

36

3132

POST−SB1390

C941H

Propeller Shaft and Bevel Gear ShaftsFigure 5-1-43



Page 5-1-114May 23/2003


1. Preformed Packing2. Oil Transfer Tube3. Preformed Packing4. Oil Nozzle, No. 4 Bearing5. Retaining Ring6. Retaining Ring7. Oil Transfer Tube Adapter8. Preformed Packing9. No. 4 Bearing Oil Nozzle

10. Preformed Packing11. Propeller Shaft Oil Transfer Tube13. Preformed Packing14. Propeller Shaft15. Retaining Ring16. Oil Transfer Tube Housing

Assembly17. Oil Transfer Bosses18. Preformed Packing (Pre-SB1223)19. Packing Retainer (Pre-SB1223)20. Spanner Nut21. Keywasher22. Front Accessory Drive Bevel

Gear23. Adjusting Spacer24. Preformed Packing25. Flanged Ball Bearing26. Packing Retainer (Pre-SB1223)27. Transfer Tube28. Preformed Packings29. Oil Seal Runner (Pre-SB1431/

Post-SB1431)30. Thrust Bearing Cover31. Plain Washer32. Self-locking Nut33. Bolt34. Plain Washer

35. Oil Seal Retaining Ring(Pre-SB1137)Oil Seal Split Retaining Ring(Post-SB1137 and PT6A-20AEngines)

36. Oil Seal37. Preformed Packing38. Transfer Tube39. Bolt (Pre-SB1223)40. Keywasher (Pre-SB1223)41. Preformed Packing (Pre-SB1223)42. Packing Retainer (Pre-SB1223)43. Shaft Sleeve (Pre-SB1223)44. Preformed Packing (Pre-SB1223)45. Power Turbine Governor and

Tachometer Drive BevelGearshaft

46. Adjusting Spacer47. Retaining Rings48. Adjusting Spacer49. Governor Drive Couplings50. Retaining Rings51. Propeller and Overspeed

Governor Drive Bevel Gearshafts52. Nipple and Cover (Post-SB1227)53. Gasket (Post-SB1227)54. Propeller Shaft Oil Seal Support

Half Rings (Post-SB1390)55. Preformed Packing (Post-

SB1431)B Pre-SB1124C Post-SB1124 and PT6A-20A

EnginesD Pre-SB1227E Post-SB1227



Page 5-1-115May 23/2003

18 25 19 20

1017

12 1314

16

17 15B

A27

2324

11

2221

67

89

29

2 3

4 5

POST−SB1263PRE−SB1397

POST−SB1397

1

128 29

30

26

C952C

Second-stage Planet Gear CarrierFigure 5-1-44



Page 5-1-116May 23/2003


1. Planet Gearpin2. Gearshaft3. Planet Gear Assembly4. Keywasher5. Gearpin Screw6. Retaining Plate7. Ring Gear8. Plain Nut9. Keywasher

10. Second Stage Planet Gear Carrier (Pre-SB1124)11. Flanged Roller Bearing12. Oil Nozzle13. Flow Restrictor14. Oil Nozzle Cover15. Bolt16. Keywasher17. Gaskets18. Oil Nozzle19. Keywasher20. Bolt21. Keywasher22. Bolt23. Keywasher24. Bolt25. Second Stage Reduction Carrier (Post-SB1124 and

PT6A-20A Engines)26. Lockpin (Pre-SB1397)27. Woodruff Key (Post-SB1397)28. Preformed Packing29. Oil Separator (Pre-SB1397)

Oil Strainer (Post-SB1397)30. Oil Seal (Post-SB1397)A. Pre-SB1124B. Post-SB1124 and PT6A-20A Engines



Page 5-1-117May 23/2003

A

A

6 7 6 8

29

3029

2827

2625

2423

2240

2120

19

1314

12

2120

19

1817

1615

15

PRE−SB1223

POST−SB1223

39

38

37

36

35

34

3132

33

1 2 3

4

5 6 78 7 6 9 10

11

12

C1587A

Reduction Gearbox Front Housing ExternalsFigure 5-1-45



Page 5-1-118May 23/2003


1. Washer2. Self-locking Nut3. Propeller Governor Mounting Gasket4. Preformed Packing5. Front Case Assembly6. Preformed Packing7. Packing Retainer8. Oil Transfer Tube9. Preformed Packing

10. Cover11. Plain Washer12. Bolt13. Strainer14. Gasket15. Bolt16. Plain Washer17. Packing Cover (Pre-SB1223)18. Preformed Packing19. Flanged Oil Transfer Tube20. Preformed Packing21. Preformed Packing22. Chip Detector and Cover or Drain Plug (Ref. SB1217)23. Preformed Packing24. Bolt25. Plain Washer26. Scavenge Oil Strainer Plug27. Preformed Packing28. Strainer29. Preformed Packing30. Oil Transfer Gallery31. Bolt32. Pressure Tapping Connector33. Preformed Packing34. Plain Seal35. Preformed Packing36. Seal Carrier37. Power Turbine Governor and Tachometer Gasket38. Washer39. Self-locking Nut40. Chip Detector (Post-SB1217)



Page 5-1-119May 23/2003

(5) Unlock keywashers (21) and remove bolts (22), keywashers, and retaining plates(6) securing second stage reduction ring gear (7) to front case. Remove ring gear.

(6) Remove eight self-locking nuts (32, Fig. 5-1-43) and plain washers (31) securingthrust bearing cover (30) and flanged ball bearing (25) to front case.

(7) Remove bolts (12, Fig. 5-1-45) and plain washers (11) securing transfer tubelocating cover (10) to front case (5). Remove cover and preformed packing (9).

(8) Withdraw oil transfer tube (8) from front case using Puller (PWC30128-02). Removepreformed packing (6) and packing retainers (7) from tube.

(9) Pre-SB1223: Remove bolts (15) and plain washers (16) securing packing cover(17) and flanged oil transfer tube (19) to front case. Remove cover and preformedpacking (18). Withdraw flanged oil transfer tube from front case using Puller(PWC30128-01). Remove preformed packings (20) and (21).

(10) Post-SB1223: Remove bolts (15) and plain washers (16) securing flanged oiltransfer tube (19) to front case. Withdraw flanged oil transfer tube from frontcase using Puller (PWC30128-01). Remove preformed packings (20) and (21).

(11) Remove bolt (24) and plain washer (25) securing scavenge oil strainer plug (26) tofront case. Remove plug, preformed packing (27) and strainer (28).

(12) Remove bolts (31) securing torquemeter pressure tapping connector (32) to frontcase. Remove connector and preformed packing (33).

(13) Remove preformed packing (4) from transmitter boss on front case.

(14) Remove oil strainer (13) from cored passage at rear of front case.

(15) Remove self-locking nuts (2) and plain washers (1) securing propeller governormounting gasket (3) and overspeed governor gasket (14) to respective mountingpads, and remove gaskets.

(16) Pre-SB1217: Remove drain plug (22) and preformed packing (23).

(17) Post-SB1217: Remove chip detector cover, chip detector (40) and preformedpacking (23).

(18) Remove self-locking nuts (39) and plain washers (38) securing power turbinegovernor and tachometer gasket (37) to front case, and remove gasket.

(19) Remove seal carrier (36) from front case using Puller (PWC30046-51). Removepreformed packing (35) and seal (34) from carrier.

CAUTION: DO NOT ROTATE FRONT CASE DURING THE FOLLOWING STEP.DAMAGE COULD RESULT SHOULD THE BEVEL GEARSHAFTS (45 AND51, Fig. 5-1-43) CONTACT OIL TRANSFER HOUSING ASSEMBLY (16).

(20) Carefully lift front case from propeller shaft by tapping with fiber drift. Place case onbench with flange A facing up.



Page 5-1-120May 23/2003

(21) Unlock keywashers (23, Fig. 5-1-44) and remove bolts (24) and keywasherssecuring flanged roller bearing (11) to front case.

(22) Remove bearing retainer from propeller shaft, install Puller (PWC30063) andremove bearing from front case.

(23) Remove oil transfer gallery (30, Fig. 5-1-45) from case using a fiber drift. Removepreformed packings (29).

61. PROPELLER SHAFT

A. Disassemble propeller shaft (See Fig. 5-1-43):

(1) Pre-SB1223: Remove shaft sleeve (43) and oil transfer housing (16) (as anassembly) from propeller shaft (14). Unlock keywasher (40) and remove bolt (39) andkeywasher securing shaft sleeve to oil transfer housing. Using Pusher(PWC30224), remove shaft sleeve from oil transfer housing. Remove packingretainer (42) and preformed packings (41) and (44) from shaft sleeve, and packingretainer (19) and preformed packing (18) from oil transfer housing.

(2) Post-SB1223: Remove oil transfer housing (16) from propeller shaft (14).

CAUTION: A LATER CONFIGURATION, P/N 3109950-01, SPANNER NUT (20) HASLEFT-HAND THREADS.

(3) Unlock keywasher (21) and remove spanner nut (20) and keywasher using Socket(PWC32430), Wrench (PWC31050), Drive bar (PWC31515) and Adapter(PWC32422).

(4) Remove bevel gear (22) and adjusting spacer (23) from shaft.

(5) Remove flanged ball (thrust) bearing (25) from shaft using Puller (PWC30435)(Post-SB1034 and PT6A-20A Engines) or Puller (PWC30450) (Pre-SB1034).Remove and discard preformed packing (26).

(6) Remove thrust bearing cover (30) complete with oil seal (36), retaining ring (35),gasket (53), and half-rings (54), where applicable.

(7) Carefully remove oil seal runner (29) from shaft (4). On Post-SB1381/1431installations, remove preformed packing (55) from shaft and discard.

(8) Remove two oil transfer tubes (27) and (38) from thrust bearing cover. Removepreformed packings (37)( and (28) from tubes.

(9) Remove seal retaining assembly from thrust bearing cover (30) as follows:

(a) Pre-SB1137: Remove bolts (33) and washers (34) securing retaining ring (35)to thrust bearing cover.

(b) Post-SB1137, Pre-SB1227, Post-SB1381: Remove bolts (33) and washers (34)securing retaining ring halves to thrust bearing cover.



Page 5-1-121Jul 01/2005

(c) Post-SB1227: Remove bolts (33) and washers (34) securing retaining ring ,gasket (53) and support half-rings (54) (Post-SB1390) to thrust bearing cover.

(10) Remove seal (36) and seal spacers, if applicable, from thrust bearing cover, anddiscard.

NOTE: Alternative oil seal with spacers may have been installed as field repair.

(11) Remove cover and nipple (52) from thrust bearing cover. Remove preformed packingfrom nipple cover.

(12) Remove propeller shaft from base.

(13) Remove oil transfer tube assembly (2) from bore of propeller shaft.

62. PROPELLER SHAFT OIL TRANSFER TUBE (Pre-SB1124)

A. Disassemble propeller shaft oil transfer tube assembly (See Fig. 5-1-43):

(1) Remove preformed packings (1 or 3)) from oil transfer tube assembly (2).

NOTE: No. 4 bearing oil nozzle (4) is not normally removed from propeller shaftoil transfer tube; however, if engine oil system has been contaminated, thenozzle must be removed in order to clean oil transfer tube. (Ref. Part 8)

63. PROPELLER SHAFT OIL TRANSFER TUBE (Post-SB1124 AND PT6A-20A ENGINES)

A. Disassemble propeller shaft oil transfer tube assembly (Ref. Fig. 5-1-45):

(1) Remove retaining ring (6) securing transfer tube adapter (7) in propeller shaft oiltransfer tube (11) and withdraw adapter using Puller (PWC30128-04). Removepreformed packing (8) from adapter.

(2) Remove retaining ring (13) and remove oil nozzle (9) from transfer tube using Drift(PWC30515). Remove preformed packings (10) and (12).

64. FRONT ACCESSORY DRIVES

A. Remove accessory drives from reduction gearbox front case (See Fig. 5-1-43):

(1) Remove retaining ring (47, Detail A) and adjusting spacer (46) securing power turbinegovernor and tachometer drive bevel gearshaft (45) in front case and withdrawgearshaft assemblies.

(2) Remove retaining rings (47) and adjusting spacers (48) securing bevel gearshaftassemblies (51) in front case. Remove gearshaft assemblies.

(3) Disassemble propeller governor and overspeed governor bevel gearshaft assemblies(51) by releasing internal retaining rings (50) using Compressor (PWC30220).Separate drive couplings (49) from respective gearshafts.



Page 5-1-122Jul 01/2005

65. SECOND-STAGE REDUCTION PLANET GEAR CARRIER AND OIL NOZZLES

A. With planet gear carrier (10 or 25, Fig. 5-1-44) installed on Holding Fixture (PWC30131),disassemble planet gear carrier and remove oil nozzles as follows:

(1) Unlock keywasher (4) and remove planet gearpin screws (5) and keywashers.Remove oil seal (30) (Post-SB1397) from counterbore of gearpin screws anddiscard.

(2) Remove gearpin assemblies (1), gearshafts (2) and planet gears (3) from carrier.

(3) Post-SB1397: Using Puller (PWC30128-6), extract strainer (29) and preformedpacking (28) from gearpin (1). Discard preformed packing.

NOTE: Retain gear shafts and planet gears in sets by appropriate vibropeenindexing (if not previously marked), relative to their positions on carrier (i.e.1,2,3,4 and 5), to ensure their installation in same locations.

(4) Post-SB1124 and PT6A-20A Engines: Unlock keywashers (19) and remove bolts(20), keywashers and oil nozzles (18) from carrier (25).

(5) Pre-SB1124 : Unlock keywashers (16); remove bolts (15), keywashers nozzlecovers (14), gaskets (17), oil nozzles (12) and flow restrictors (13) from carrier(10).

(6) Remove planet gear carrier from holding fixture.



Page 5-1-123/124May 23/2003

PART 5 LEP

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