Piper Navajo PA-31 User manual

PIPER
AIRPLANE
SERVICE
MANUAL
CARD
1OF5
PA-31
PA-31-300
PA-31-325
PIPER
AIRCRAFT
CORPORATION
(PART
NUMBER
753704)
lAl

PIPER NAVAJOSERVICE MANUAL
AEROFICHE EXPLANATION
AND REVISION STATUS
Servicemanual
informationincorporated
inthissetofAerofiche
cardsis arranged
in accordancewith
general specifications
of Aerofiche
adoptedbyGeneral
AviationManufacturer's
Association.Information
compiled in this Aerofiche service manualis kept current by revisions distributed
periodically.
These
revisions supersedeall previousrevisionsandare completeAerofiche
card replacements
and supersede
Aerofichecardsofsamenumberinset,except
asnotedbelow.
Identification
of revisedmaterial: Revisedtext andillustrationsareindicatedbya blackverticalline
along the left-handmarginof the frame,oppositerevised,
or addedmaterial.
Revision
lines indicateonly
current revisionswith changesand additions
to existingtext and illustrations.
Changesin capitalization,
spelling,punctuation,indexing.
physicallocation
of materialor complete
pageadditionsarenot identified
by revisionlines.
Revisions to service manual 753 704 issuedOctober 1, 1966are as follows:
Revisions PublicationDate Aerofiche
CardEffectivity
ORG661001
CR720707
CR791012
PR800923
PR810311
P R8 10924
PR820129
PR821115
PR831012
PR840302
PR840503
IR860429
IR860921
IR870505
IR871009
IR900313
PR940218
IR941202
October 1,1966
July 7, 1972
October 12, 1979
September23, 1980
March 11.1981
September24, 1981
January29, 1982
November 15,1982
October 12,1983
March 2, 1984
May 3,1984
April29,1986
September21, 1986
June 12, 1987
June 15, 1988
Marchl3, 1990
February 18,1994
December2, 1994
1, 2, 3,4 and5
1,2, 3,4 and 5
1,2, 3,4 and5
1,2, 3,4 and5
1,2, 3,4 and5
1,2, 3,4and5
1,2, 3,4and5
1,2, 3,4 and5
1
1
1
1
2
1
1,2, 3,4 and 5
1
INTERIM REVISION
REVISIONS APPEAR IN THE INTRODUCTION AND
SECTION III OF CARD 1. PLEASE DISPOSE OF YOUR
CURRENT CARD 1, AND REPLACE IT WITH THE
REVISED CARD.
Consult the Customer Service Information Aerofichefor currentrevision dates for this manual.
Revised: February18,1994
InterimRevision: December2,1994 1A2

TABLEOFCONTENTS
AEROFICHE CARD NO. 1GRID NO.
I
III
IV
V
INTRODUCTION ........................
HANDLING AND SERVICING ...........
INSPECTION ............................
STRUCTURES ...........................
SURFACE CONTROLS ..................
...........
...........
...........
...........
...........
1A17
1A20
1D9
1E11
1H20
AEROFICHE CARD NO. 2
VI
VII
VIII
VIIIA
VIIIB
HYDRAULIC SYSTEM...................
LANDING GEAR AND BRAKE SYSTEM .
POWER PLANT(PA-31 Turbo)...........
POWER PLANT(PA-31-300) ............
POWER PLANT (PA-31-325) ............
...........
...........
...........
...........
...........
2A9
2E4
2H6
2K8
2K18
AEROFICHE CARD NO. 3
IX
XFUELSYSTEM ..........................
INSTRUMENTS ......................... ...........
...........
3A8
3C21
XI
AEROFICHE CARD NO. 4
ELECTRICALSYSTEM ..................
AEROFICHE CARD NO. 5
ELECTRONICS..........................
HEATING AND VENTILATING...........
ACCESSORIES AND UTILITIES .........
4A7
XII
XIII
XIV
5A9
5B3
5E1
1A3

INTENTIONALLY LEFT BLANK

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS
Figure Aerofiche
GridNo.
2-1. Three-View of Navajo .................. ......... ... ................ 1A23
2-2. Station Reference Lines ..................... .......... ................. .B4
2-3. Access Plates and Panels, Fuselage Interior ................................. 1B7
2-4. Access Plates and Panels. Fuselage and Empennage ................ ............ 1B8
2-5. Access Plates and Panels. Wings ............................................. B9
2-5a. Torque Wrench Formula ........................... ..... .......... ..... 1B13
2-6. Jacking Arrangements ...................................................... 1B14
2-7. Weighing the Airplane ................................................... 1B15
2-8. Leveling Longitudinally .............................................. IB15
2-9. Leveling Laterally ........................................ ................. 1B15
2-10. Tow Turn Limits Indicator ........................................ ......... B17
2-11. Service Points ............................................................ 1B19
2-12. Servicing Landing Gear Shock Struts ........................................ IB22
2-12a. Tire Balancer ............................................................. 1C1
2-13. Lubrication Chart (Landing Gear. Main) ............. ........................ 1C10
2-13a. Lubrication Chart (Landing Gear, Nose).................................... ICII
2-13b. Lubrication Chart (Control System) ..... ......... ................ ............ 1C12
2-13c. Lubrication Chart (Control System) (cont.) ................................... 1C13
2-13d. Lubrication Chart (Power Plant. Propeller and Cowl Flap) ..................... IC14
2-13e. Lubrication Chart (Doors and Seats) ........................................ IC15
2-14. Fabricated Jack Stand for Piper Jack, Part No. 18338-00....................... 1C19
2-15. Fabricated Tail Stand ......................... ............................. 1C20
2-16. Removal of Cherrylock Rivets ............................................... IDI
2-17. Identification of Aircraft Fluid Lines .......................................... 1D2
3-1. Wing Flap Transmission Inspection .................... ....................... ID12
3-2. Wing Flap Actuator Cable - 100 Hour Inspection .............................. ID13
3-2a. Wing Flap Actuator Cable - 500 Hour Inspection ............................. ID14
3-3. Friction Reduction in Wing Flap System ................................... ............... 1D18
3-4. Wing Flap Motor.......................................................... 1D19
3-5. Fuel Selector and Crossfeed Valve Control Cables ................... .......... ID21
3-6. Inspection of Aileron Sprocket and Chain .................................... 1D22
4-1. Landing Light ............... .................................... .......... IE16
4-2. Aileron and Flap Installation ................................................ 1E18
4-3. Methods of Blocking Trim Cables ........................................... 1E22
4-4. Fuselage Cradle ........................................................... 1E23
4-5. Wing Installation .......................................................... 1E24
4-6. Empennage Installation ..................................................... 1F3
4-7 Windshield Installation (Standard) ........................................... IFII
4-8. Windshield Installation (Heated) ............................................. 1F12
4-9. Windshield Wiper ........................................................ IF15
4-10. Side Window Installation (Typical) ......................................... IF17
4-11. Cabin Entrance Door Latch Assembly....................................... 1F19
4-12. Nacelle Wing Lockers ...................................................... 1F23
Revised: 3/2/84 1A5

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS (cont.)
Figure Aerofiche
Grid No
4-13 Cargo Door................................................. IGI
4-14. Pilot Door.......... ............................................... 1G
4-15. Aileron Balancing.1G7
4-15. Aileron Balancing ......................................................... IG7
4-16. Elevator Balancing .... ............................................ 1G8
4-17 Elevator Trim Weight Installation ............................................ IG10
4-18. Elevator Trim Weight Installation (Without Wing Lockers) .................. .. .. 1G11
4-19. Elevator Trim Weight Installation (With Wing Lockers) ......................... IGII
4-20. Elevator Friction Measurement......................................... 1G
4-21. Rudder Balancing.1G14
4-1. Rudder Balancing ......................................................... 1G14
4-22. Balancing Rudder .......................................................... 1G15
4-23. Balancing Rudder ....................................................... IG16
4-24. Empennage and Nacelle Skin Material and Thickness ........................... 1G17
4-25 Fuselage and Wing Skin Material and Thickness ............................... 1G19
4-26. Typical Access Holes ......... 1G21
4-27 Installation of Balance Weight Anchor Nut. Elevators P N 40140-00
and P N 40140-01 1G22
and P N 40140-01 ........................................................ 1G22
4-28. Installation of Balance Weight Anchor Nut. Elevators P N 43757-00
and P N 43757-01 .......................................... 1G24
4-29 Installation of Rudder Balance Weight Anchor Nut ............................. 1H1
4-30. Ballast Weight Lifting Handle (PA-31-300) ..................................... 1H2
4-31 Surface Scratches Abrasions or Ground-In-Dirt ...................... .... 1H7
4-32. Deep Scratches. Shallow Nicks and Small Holes ............... 1H7
4-33. Mixing of Epoxy Patching Compound ....................................... 1H8
4-34. Welding Repair Method.............................. 1H8
4-35 Repairing of Cracks.... ..... .. 1H10.. ........... 1H10
4-36. Various Repairs ................ 1H11
4-37 Repair of Stress Lines ................ 1
4-38. Repair of Impacted Damage ................................................. 1
4-39 Installation of Radome Erosion Shield ....................... H 17
4-40 Wing,Front Spar Attachment Bulkhead Repair ................................ 1H19
5-1 Control Column Installation ....................................... 114
5-1a. Correct Method of Installing Rod End Bearings ................................
5-2. Ailcron and Aileron Trim Controls ...........
5-3. Installation of Bellcrank R in Tool....................................... 1114
5-4. Installation of Aileron Rigging Tool .................................. ..111
5-5 Elevator and Eleator Trim Contols........................................... 1121
5-6. Installation of Elevator Rigging Tool .......................................
5-7 Elevator Travel Stops ....................................... .1123
5-7a. Safety Wiring Control Surface Stops ................................... .1124
5-8. Methods of Blocking Trim Cables .............. 111
5-8a. Cable Routing on Elevator Trim Sero ............................... 1J4
5-9 Rudder Pedal Installation ............................................... ....
5-10. Rudder and Rudder Trim Controls ........................................ 1J10
5-11 Clamping Rudder Pedals in Neutral Position ................................... 1J13
5-12. Installation of Rudder RiggingTool
5-12. Installation of Rudder Rigging Tool .......................................... 1G13
5-13. Trim Screw Assembly 5-13. Trim Screw Assembly ....................................................... 1J13
5-14. Control Pedestal............. 1J18
Revised: 3/2/84 1A6

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS (cont.)
Figure Aerofiche
Grid No.
5-15.
5-16.
5-17
5-18.
5-19.
5-20.
5-21
5-23.
5-24.
5-25.
5-26.
5-26a.
5-26b
5-27.
5-28.
5-29
6-1
6-2.
6-3.
6-4.
6-5.
6-6.
6-7
6-8.
6-9.
6-10.
6-11
6-12.
6-13.
6-14.
6-15.
6-16.
6-17
6-18.
6-19
6-20.
6-21.
6-22.
6-23.
6-24.
6-25.
6-26.
6-27.
Flap Controls (Piper System) ................................................
Flap Circuit Schematic (Dukes System)........................................
Flap Rigging Check ........................................................
Flap System Diagram (Calco) ................................................
Motor Assembly. Exploded View.............................................
Flap Controls (Calco System) ................................................
Deleted ...................................................................
Deleted ...................................................................
Deleted . . . ...........................................
Deleted ...................................................... ............
Flap Rigging Adjustments ...................................................
Use of Flap Rigging Tool ....................................................
Amplifier - Electrical Schematic (Calco) P N8482 .............................
Amplifier - Electrical Schematic (Calco) P N 8502M I ..........................
IJ20
IJ24
IKI
IK3
IK5
IK8
IK16
1K16
1KI8
1K21
1L 15
Fabricated Bellcrank Rigging Tool ..........................
Fabricated Aileron - Elevator Rigging Tool ..................
Fabricated Rudder Rigging Tool ...........................
Schematic Diagram of Hydraulic System (Ozone 2930-1) ......
Schematic Diagram of Hydraulic System (Ozone 2930-3) ......
Schematic Diagram of Hydraulic System (Ozone 2930-5and -7)
or (Wiebel 2135-1 and -3)................................
Schematic of Power Pack Electrical S\stem ..................
Power Pack Installation (Ozone 2930-1) .....................
Power Pack Installation (Ozone 2930-3) .....................
Power Pack Installation (Ozone 2930-5and -7) or (Wiebel 2135-
Identification of Power Pack ...............................
Location of Power Pack Components (Ozone) ................
Hydraulic Power Pack (Ozone 2930-1) ......................
Hydraulic Power Pack (Ozone 2930-3. -5 and -7) .............
Power Pack Manifold (Ozone) .............................
Power Pack Handle Release (Ozone) ....... ................
Safetying Control Arms (Ozone) ............................
Timing of Selector Spool (Ozone). ..........................
Handle Release Adjustment (Ozone) ........................
Location of Power Pack Components (Wiebel Tool) ..........
Hydraulic Power Pack (Wiebel Tool). .................
Power Pack Manifold (Wiebel Tool) ........................
Power Pack Handle-Release Mechanism (Wiebel Tool) ........
Safetying Control Arm (Wiebel Tool) ......................
Indexing of Selector Spool (Wiebel Tool) ....................
Handle Release Adjustment (Wiebel Tool) ...................
Landing Gear Selector Mechanism. Serial Nos. 31-5 thru 31-511
Landing Gear Selector Mechanism. Serial Nos. 31-512 and up..
Hand Pump (Ozone)......................................
Hand Pump (Wiebel Tool) .................................
.................
. . .. .. ...
. . . . . . . .
. . .. .. ...
. . .. .. ...
..........
..................
.. .. .... .. ... .. ..
...................
..............
...................
... .. ... ... .. ... ..
...................
...................
..................
.. ... .... .. ... .. .
.. ... ... ... ... .. .
11.16
1l.17
2A17
2A18
2A19
2A20
2A21
2A22
2A23
2B13
2B16
2B21
2B22
2Cl
2C1
2C4
2C9
2C I
2C14
2C15
2C17
2C21
2C24
2D2
2D5
Revised: 3/2/84 1A7

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS
(cont.)
Aerofiche
Figure Grid No.
6-28. Hydraulic System Installation ........ ...................................................... 2D6
6-29. Gear Actuating Cylinder (Ozone) ........................................................................................ 2D8
6-3 0. Gear Actuating Cylinder (W
iebel Tool)...............................................................2D10
6-31. Gear Door Actuating Cylinder (Ozone)....... .......................................... 2D12
6-32. Gear Door Actuating Cylinder (WiebelTool)......................................................15
6-33. Hydraulic Filter ....................................................................................... 2D16
6-34. Hydraulic Pum p.............................................................................................................. 2D19
6-35. Power Pack Test Harness Schematic..................................................................................... 2D23
7-1. Nose Gear Oleo Strut Assembly ........ ........................................................... E8
7-2. Nose Landing Gear Installation........................................... ................................ 2E17
7-3. Clamping Rudder Pedals in Neutral Position.............................................................................2E22
7-4. Rudder Pedals Neutral Angle .................................................................................... 2E22
7-5. Aligning Nose Gear. ............................................. 2E22
7-6. Main Gear Oleo Strut Assembly................................................................................................
2F
7-6a. Correct Method of installing Rod End Bearings
............ ............................................... 2F4
7-7. MainLanding Gear Installation (Left)............................................................................ 2F7
7-8. Actuator Cylinder Lock Installation...........................................................................................
2F
7-9. Aligning Main Gear ..........
............................................................................................... 2F12
7-10. Landing Gear Circuit Diagram (S/N 31-2to 31-184 Inc.)
........................................... 2F16
7-10a. Landing Gear Circuit Diagram (S/N 31-185and up) ............................................. 2F17
7-11. Adjusting Main Gear Down Light Switch............................................................................ 2F18
7-12. Gear Warning Switches Installation........................................... .................
2F20
7-13. Nose W
heel Assembly ................................................................
7-14. Main W
heel Asse m bly.....................................................................................2F24
7-15. Brake Installation .................................................................................................. 2G
7-16. W
heel Brake Assembly (30-68 and 30-68A)
........................................... ........ ... 2G3
7-16a. Removal and Installation of Anchor Bolts...............................................................................2G4
7-16b. Wheel Brake Assembly (30-95 and 30-95A ...................................... 2G5
7-17. Brake M
aster Cylinder Assembly ..............................................................................................
2G8
7-18. Parking Brake ValveAssembly ........................................................................................... 2G10
7-19. Bleeding Brake ................... ........................................................................... 2G
I
7-19a. Nose Gear Wear Limits .. ....................................................................... 2G12
7-19b. Main Gear Wear Limits ............................................................................................ 2G16
7-20. Fabricated Tool, Checking Nose Wheel Alignment ............................................... 2H2
7-21. Fabricated Tool, Checking Nose Gear Drag Link Travel ..............................................
2H3
7-22. Fabricated Tool, Checking Main GearSide Brace Link Travel............................................... 2H4
7-23. Fabricated Tool, Checking Main GearToe-inAdjustment............................................... 2H5
8-1. Engine Cowling ........................................................................................................ 12
8-2. Cowl Flap Transmission and Sender Assembly..................................................................... 2H14
8-3. Propeller Installation ......................................................................................................... 2H17
8-4. Typical Nicks and Removal Method........................................................................... 2H18
8-5. Propeller Governor................................................................................................... 2H22
8-6. Engine Installation.......................................................................................211
8-7. Schematic Diagram of Turbocharger System............................................... ................. 217
8-7a. Turbocharger Installation (PA-310-325)....... ............................................. 218
8-7b. Exhaust W tegate....................................................................................................................2I11
8-8. Fuel Injector ...............................................................................................................................
2117
Revised: 2/18/94 LANDING
GEAR AND
BRAKE
SYSTEM
1A8

PIPERNAVAJOSERVICEMANUAL
LIST OF ILLUSTRATIONS (cont.)
Figure
8-9.
8-10.
8-11.
8-12.
8-13.
8-14.
8-15.
8-16.
8-17.
8-18.
8-19.
8-20.
8-21.
8-22.
8-23.
8-24.
8-25.
8-26.
8-27.
8-28.
8-29.
8-30.
8-31.
8A-1.
8A-2.
8A-3.
8B-1.
8B-2.
8B-3.
8B-4.
8B-5.
8B-6.
8B-7.
8B-8.
8B-9.
8B-10.
8B-11.
8B-12.
8B-13.
8B-14.
8B-15.
8B-16.
8B-17.
8B-18.
Fuel-Air Bleed Nozzle ....................
Contact Points .........................
Rotor Holding Tool Installed ................
Timing Kit Installed ......................
Aligning Timing Marks SingleContact Assembly Magneto
Forming Leads in Breaker Compartment ..........
Engine Timing Marks .....................
Magneto Timing Marks ....................
Removing Spring From Lead Assembly ..........
Assembly Tool .........................
Using Assembly Tool .....................
Measuring Lead Assembly Length ..............
Cutting Metallic Braid From End of Lead .........
Unbraiding Metallic Shielding ................
Forming Shielding Around Ferrule .............
Ferrule Seating Tool .....................
Needle . .. ... . .............. . ......
Measuring Wire From Top of Ferrule ............
Installing Grommet Over Lead Assemblies .........
Lead Assembly Installed in Grommet ..... ......
Wire Doubled Over for Installation of Eyelet .......
Ignition System Schematic (PA-31 Turbo) .........
Removing Frozen Spark Plug ................
Propeller Governor ......................
Engine Installation ......................
Fuel-Air Bleed Nozzle ....................
Engine Installation ......................
Height of Spring in Distributor Block Tower .......
Contact Points .........................
Engine Timing Marks ......................
Timing Light Connected to Magneto ............
Timing Marks on Magneto Rotor .......
Painted Tooth Centered in Timing Window ........
Timing Mark on Rotor Aligned with Pointer (Right-Hand Rotation)
Timing Light Connected to Magneto ............
Timing Light Connected to Magneto and Breakers ....
Checking Harness Lead Continuity .............
Checking Harness Lead Insulation Resistance .......
Modified Pliers .........................
Removing Spring From Lead Assembly ..........
Assembly Tool .........................
Using Assembly Tool .....................
Ferrule Positioned Under Braid ...............
Ferrule Seating Tool 11-7074 ................
Rotation)
Aerofiche
Grid No.
......... . . . . . . 2118
............... 2120
............... 2122
.......... ..... 2122
.......... .... .2I23
....... ... .. ... 2124
. ... .. . .. . ..... 2Jl
. ..... . ... ... .. 2J1
. .. ........ . . . . 2J3
.... .. . .. .... .. 2J4
...... . ... .. . . .2J4
............... 2J4
. ... ... ... ... . . 2J5
............... 2J5
... .... ... .. .. . 2J6
............... 2J6
... .... .. .. . . . . 2J6
... . ... ... .. . . . 2J7
. .. . ... ... .. . . .2J7
... . ... .. . . . . . . 2J8
. .. . ... . .. .. . . . 2J8
. . .. ........ . . . 2J9
. . . . . . . . . . . . . . . 2J1l
. ............ .. 2K
12
. ...... ... ..... 2K13
. ......... ..... 2K16
............... 2K23
. . . . . . . . . . . . ... 2L1
.. . . . . . . ....... 2L2
. . . . .. . . ..... ..2L4
. . . . .. . . . ..... . 2L4
... .. . ... ..... . 2L5
...... ... ..... . 2L5
otation) .......... 2L7
............ . .. 2L7
..... .. . ..... . . 2L7
. .. . .. . . ....... 2L7
.............. . 2L11
............... 2LII
. .. . .. . ........ 2L11
. ... ... ... . . . .. .2L12
............... 2L14
. .. . ... ... . . . . . 2L14
8B-19. Position of 11-8627 Kit and Contact Spring at Start of Installation .. 2L14
Revised: 11/15/82
1A9

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS (cont.)
Figure Aerofiche
Grid No.
8B-20. Position of 11-8627 Kit and Contact Spring After Installation ................... 2L14
8B-21. Lubricating Sleeve .......................... ............................... 2L15
8B-22. Lubricating Ferrule Shoulder ............................................... 2L15
8B-23. Ignition System Schematic (PA-31-325) ....................................... 2L17
9-1. Fuel System Schematic (PA-31-310) .. ....................................... 3A11
9-la. Fuel System Schematic (PA-31-300) ......................................... 3A12
9-lb. Fuel System Schematic (PA-31-325) ...................... ................... 3A13
9-1c. Fuel Boost Pump Installation (PA-31-325) ................................................. 3A15
9-1d. Fuel Cell Installation (Nacelle Optional) PA-31-325 only ........ ............ 3A16
9-2. Fuel Cell Installation (Main Inboard) ........................................ 3A21
9-3. Fuel Cell Installation (Auxiliary Outboard) .............................. 3A22
9-4. Installation of Fuel Valve Drain Plate ........................................ 3A24
9-5. Fuel Gauge Adjustment Wires............................................... 3B3
9-6. Scott Fuel Selector Valve ................................................... 3B12
9-7. Crossfeed Valve ........................................................... 3B13
9-8. Emergency Shut-Off Valve .................................................. 3B15
9-9. Fuel System Installation (PA-31 Turbo) ............................. ......... 3B16
9-9a. Fuel System Installation (PA-31-300) ........................... ................. 3B18
9-10. Adjustment of Crossfeed %alve .............................................. 3B20
9-1
1. Fuel Filter ................................................................ 3B22
9-12. Electric Fuel Pump (PA-31-310 and -325) ......... .................. 3C2
9-12a. Electric Fuel Pump (PA-31-300) ............................................. 3C6
9-13. Fuel Cell Tie Detail ........................................................ 3C11
9-14. Low Fuel Warning Sender Sealing ........................................... 3C12
10-1. Instrument Panel (Typical) .................................................. 3C23
10-2. Instrument Air System Installation (Typical) .............. ................ 3D2
10-2a. Single Attitude and Directional Gyro Installation .............................. 3D7
10-3. Dual Attitude and Directional Gyro Installation ....................... ........ 3D8
10-4. Single or Dual Attitude and Directional Gyro Installation with
Deicer Boots ............................................................ 3D10
10-5. Test Take-Off ............................................................. 3D 14
10-6. Single or Dual Attitude and Directional Gyro Installation with
H-14 Autopilot .......................................................... 3D15
10-7 Pneumatic Relay .......................................................... 3D17
10-8. Single or Dual Attitude and Directional Gyro Installation with
Deicer Boots and H-14 Autopilot .......................................... 3D19
10-9. Digital Clock ............................................................. 3D22
11-1. Overhead Switch Panel ..................................................... 4A17
11-2. Switch and Circuit Breaker Control Panel .................................... 4A18
11-3. Dual Alternator Wiring System (Delco-Remy) ................................. 4A23
11-4. Cross-Sectional View of Alternator .......................................... 4B2
Revised: 9/24/81 lA10

PIPERNAVAJOSERVICEMANUAL
LIST OF ILLUSTRATIONS (cont.)
Aerofiche
Figure Grid No.
11-5.
11-6.
11-7.
11-8.
11-9.
11-10.
11-11.
11-12.
11-13.
11-14.
11-15.
11-16.
11-17.
11-18.
11-19.
11-20.
11.21
Checking Rotor ............................
Slip Ring End Frame .........................
Checking Stator ............................
Checking Diodes ............................
Brush Holder Assembly ........................
Alternator Output Check .......................
Exploded View of Heat Sink Assembly ...............
Volt-Ohmmeter Test......................................
Jumper Connection ......................................
Regulator Checks ........................................
Relay Tests..............................................
Exploded View of Alternator ..............................
Dual Alternator Wiring System (Prestolite)..................
Removal of Rectifier .....................................
Removal of Slip Ring End Bearing .........................
Removal of Drive End Head ..............................
... . . . ...
.... . . . .
....... . .
..... . . . .
..........
.... .·. . . . .
........ . ......
...... . ........
........ . ......
. .. ... .... . . . .
11- 1. RemovalofEnd Head Bearing............................................
.11-22. Testing Rotor for Ground ................................................
.11-23. Testing Rotor for Shorts .................................................
11-24. Installation of Bearing ...................................................
11-25. Installation of Rectifier ..................................................
11-26. Terminal Assembly ......................................................
11-27. Slip Ring End Bearing Assembly ..........................................
11-28. Testing Alternator. . ............................ .......................
11-29. Brush Installation .......................................................
11-30. Internal Wiring Diagram ................................. ...............
11-31. Alternator Paralleling System .............................................
11-32. Regulator Diagram (Prestolite) ...........................................
11-33. Regulator Diagram (Lamar) ..............................................
11-34. Testing Regulator (Prestolite) .............................................
11-35. Testing Regulator (Lamar) ...............................................
11-36. Adjusting Regulator (Lamar) .............................................
11-37. Application of Overvoltage Control .......................................
11-38. Testing Overvoltage Control ..............................................
11-39 Exploded View of Gear Reduction Starting Motor ..........................
11-40. Turning Starting Motor Commutator ......................................
11-41. Testing Motor Armature for Shorts .......................................
11-42. Testing Motor Fields for Grounds .........................................
11-43. No Load Test Hook-up ..................................................
11-44. Stall-Torque Hook-up ...................................................
11-45. Door Ajar Switch (Cargo Door Installed) ..................................
11-46. Landing Light ..........................................................
.4B3
.4B3
.4B4
. 4B4
.4B6
.4B6
4B7
... 4B10
. 4B10
... 4BII
...4B13
... 4B14
... 4B15
... 4B18
...4B18
... 4B19
... 4B19
... 4B20
... 4B20
... 4B21
... 4B21
.. 4B22
... 4B23
... 4B23
.. 4C1
... 4C1
... 4C3
... 4C5
... 4C7
... 4C9
... 4C10
... 4C12
... 4C14
... 4C14
... 4C17
... 4C20
... 4C20
... 4C21
... 4C21
... 4C22
... 4D9
. 4D11
NOTE
Index for Electrical Schematics may be found in Table XI-VII. Grid 4E 15
Reissued: 10/12/79 1All

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS (cont.)
Figure Aerofiche
Grid No.
12-1.
12-2.
12-3.
12-4.
12-5.
12-6.
12-7.
12-8.
Two Year Magnesium Battery Connections ...................................
Garrett ELT Schematic .....................................................
Communications Components ELT Schematic (Early Models)...................
Communications Components ELT Schematic (Later Models) ...................
Emergency Locator Transmitter Schematic (Narco) ............................
ELT Portable Folding Antenna (Narco) ......................................
ELT Using Fixed Antenna (Narco) ..........................................
Avionic Antenna Locations ................................................
NOTE
5A12
5A18
5A20
5A21
5A22
5A24
5A24
5B1
Index for Electronic Installation Schematics may be found in Table
X11-1 Page 4A10.
13-1.
13-2.
13-3.
13-4.
13-5.
13-6.
13-7.
13-8.
13-9.
13-10.
13-11.
13-12.
13-13.
13-14.
3-15.
3-16.
13-17.
13-18.
13-19
13-20.
13-21
13-22.
13-23.
13-24.
13-25.
13-26.
13-27.
Heating and Ventilating System .............................................
Heating and Ventilating System .............................................
39D59 Heater Assembly and Combustion Air Blower. System No I .............
39D59 Heater Assembly and Combustion Air Blower. System No 2 .............
B39D59. D39D59 Heater Assembly and Combustion Air Blower
.................
Cutaway of Heater. Showing Whirling Flame (Typical) .........................
Fuel Regulator and Shutoff Valve ...........................................
Top View-Duct Switch. 39D59 Heater System No I ...........................
Top View-Duct Switch. 39D59 Heater System No. 2 and B39D59. D39D39
Heater System ..........................................................
Wiring Schematic. 39D59 Heater System No. 1................................
Wiring Schematic. 39D59 Heater System No. 2................................
Wiring Schematic. B39D59. D39D39 Heater System ...........................
Primary Power Circuit. 39D59 Heater System No. 1 ...........................
Primary Power Circuit. 39D59 Heater System No 2............................
Primary Power Circuit. B39D59, D39D39 Heater System .......................
Starting Power Circuit. 39D59 Heater System No. I ...........................
Starting Power Circuit. 39D59 Heater System No. 2 ...........................
Starting Power Circuit. B39D59. D39D39 Heater System .......................
Spark Plug Gap Adjustment (39D59 Heater) ..................................
Spark Plug Gap Adjustment and Tool (B39D59. D39D39 Heater) ...............
Spark Plug Fixture (39D18 Plug) ............................................
Wiring - Test Setup ........................................................
Test Setup for Fuel Regulator and Shutoff Valve ..............................
Suggested Design for Seal Plate. Plugs and Caps for Combustion
Tube Leakage Test.......................................................
Test Setup for Combustion Air Pressure Switch ...............................
Test Setup for Combustion Air Blower Switch ................................
Heater Assembly 39D59. System No. I ......................................
5B6
5B7
5B8
5B9
5B10
5BII
5B12
5B13
5B13
5B14
5B14
5B15
5B18
5B18
5B 19
5B20
5
B20
5B21
5B23
5B24
5C2
5C2
5C6
5C14
5C15
5C16
5C23
Revised: 9/24/81 1A12

PIPER NAVAJO SERVICE MANUAL
LIST OF ILLUSTRATIONS (cont.)
Aerofiche
Figure Grid No.
13-28.
13-29.
13-30.
13-31.
13-32.
13-33.
13-34.
13-35.
13-36.
14-1.
14-la.
14-lb.
14-2.
14-3.
.14-4.
.14-5.
.14-6.
14-7.
14-8.
14-9.
14-10.
14-11.
14-12.
14-13.
14-14.
14-15.
14-16.
14-17.
14-18.
14-19.
14-20.
14-20a.
14-20b.
14-21.
14-22.
14-23.
14-24.
14-25.
14-26.
14-27.
14-28.
14-29.
14-30.
Heater Assembly 39D59, System No. 2 .....................................
Exploded View of Heater Assembly Part No. 755 257 (28 Volt) ..................
Combustion Air Blower and Motor Assembly 41D07, System No. 1..............
Combustion Air Blower and Motor Assembly 41D07, System No. 2..............
Combustion Air Blower and Motor Assembly 89D26-1 .........................
Suggested Setup for Heater Operation Test ...................................
Wiring Connections for 39D59 Heater Operation Test. System No. 1.............
Wiring Connections for 39D59 Heater Operation Test. System No. 2.............
Wiring Connections for B39D59 Heater Operation Test ........................
Typical Oxygen System Installation (FWD Mounted Cylinder) ..................
Typical Oxygen System Installation (Aft Mounted Cylinder).
(Optional FWD Mounted Cylinder) ...... ................................
Oxygen Tubing Installation .................................................
Two-Bladed Propeller Electric Deicer Installation .............................
Three-Bladed Propeller Electric Deicer Installation ............................
Electrical Diagram Showing Cycle Sequence, Two Blades .......................
Electrical Diagram Showing Cycle Sequence. Two Blades .......................
Electrical Diagram Showing Cycle Sequence, Two Blades .......................
Electrical Diagram Showing Cycle Sequence, Two Blades .......................
Electrical Diagram Showing Cycle Sequence, Three Blades......................
Electrical Diagram Showing Cycle Sequence, Three Blades......................
Electrical Diagram Showing Cycle Sequence, Three Blades ......................
Electrical Diagram Showing Cycle Sequence, Three Blades ......................
Typical Use of Dial Indicator ...............................................
Centering of Brushes on Slip Rings ..........................................
Wiring Schematic, Electric Propeller Deicing System, Two Blades ...............
Wiring Schematic. Electric Propeller Deicing System, Three Blades ..............
Brush Block Assemblies ...................................................
Angle of Contact Brushes to Slip Rings ......................................
Repair of Lead Strip .......................................................
Installation of Deicer Boot..................................................
Wrinkled Deicers ..........................................................
Sealer Application (Boot) ........ ...........................................
Sealer Application (Lead Strap) .............................................
Propeller Blade in Low Pitch ...............................................
Propeller Blade in Feather Position ..........................................
Aft Cabin Heater Installation ...............................................
Aft Cabin Heater Schematic ................................................
Exploded View of Electric Fuel Pump and Installation .........................
5DI
5D3
5D6
5D7
5D8
5D9
5D10
5D 10
5DII
5E8
5E10
5Ell
5E14
5E15
5E16
5E16
5E17
5E17
5E18
5E18
5E19
5E19
5E22
5E22
5E24
5E24
5FI
5F6
5F7
5F10
5F10
5F12
5F12
5F13
5F13
5F23
5GI
5G2
5G4
5G9
5G10
5G11
5G12
System Installation ...............................
Service Valves ...................................
Manifold Set Operation ...........................
Test Gauge and Manifold Set ......................
Leak Test Hookup ................................
. ...... ...
...........
...........
...........
...........
Revised: 9/23/80 1A13

PIPER
NAVAJOSERVICEMANUAL
LIST OF ILLUSTRATIONS (cont)
Figure Aerofiche
Grid No.
14-31. Evacuation Hookup ........................................................ 5G13
14-32. Charging Stand ........................................ 5G15
14-33. Charging Hookup ...................................... 5G18
14-34. Compressor and Fabricated Oil Dipstick ..................................... 5G21
14-35. Magnetic Clutch 14-35. Magnetic Clutch ............................................ ........... .5H1
14-36. Expansion Valve ......................................... 5H4
14-37. Service Points ............................................................ 5H6
14-37a. Air Conditioning Outlets ................................................... 5H7
14-37b. Positioning of Airflow Probe ............................................... 5H8
14-37c. Sealing of Ducts .......................................................... 5H9
14-37d. Installation of Voi-Shan Seals ................................. 5H10
14-37e. Air Conditioning Schematic ................... ..
..... ........ ........... 5H11
14-38. Synchrophaser Installation .............. ................................... 5H21
14-39. Strobe Sensor ....................................... ................... 513
14-40. Pulse Generator .......................................................... 514
14-41. Computer Assembly ............................................... 515
14-42. Fabricated Test Box ..................................... 517
14-43. Electrical Schematic ....................................................... 517
14-44. Strobe Sensor Internal Wiring Test Unit ................... 518
.... 518
14-45. Strobe Sensor Simulator ............................................. 18
14-46. Patch Cable and Test Terminal ................... 519
14-47. Pulse Generator Simulator .................................................. 519
14-47a. Synchrophaser Schematic....................... .............. .......... 5110
14-48. Propeller Synchronizer System Installation .................. ........ .......... 5I13
14-49. Synchronizer Schematic .................................................... 5115
14-50. Mechanical Connections .................. ·.................. 5115
14-51. Fabricated Test Box .......................................... ............. 5117
14-52. Pneumatic Deicer System Installation (Early Models) .......................... 5121
14-53. Pneumatic Deicer System Installation (Later Models) .......................... 5122
14-54. Pneumatic Deicer Boot Operation ........................................... 5124
Reissued: 10/12/79 1A14

PIPER NAVAJO SERVICE MANUAL
LIST OF TABLES
Table Aerofiche
Grid No.
11-1.
11-lla.
11-11l.
II-IV.
11-V.
II-VI.
II-VII.
II-VIII.
111-l.
IV-I.
1V-II.
V-1.
V-1l.
VI-1.
V1-I.
VI-111.
V1-ll.
Vl-IV.
VII-I.
VIII-IA.
VIII-IA.
VIII-Il.
VIIIA-I.
VIIIB-I.
VIIIB-II.
VIIIB-III.
IX-I.
IX-la.
IX-II.
X-I.
X-IA.
XI-11.
X-III.
XI-I.
Xl-ll.
Xl-III.
XI-IV
XI-V.
XI-VI.
XI-VII.
XII-I.
XIII-I.
Leading Particulars and Principal Dimensions................................
Recommended Nut Torques ...............................................
Thread Lubricants ........................................................
Indicated Oxygen Pressures for Given Ambient Temperatures ..................
Consumable Materials ...................................................
Maximum Distance Between Supports for Fluid Tubing .......................
Decimal, Millimeter Equivalents of Drill Sizes................................
Decimal Conversion Chart......... ........................................
Conversion Chart ........................................................
Inspection Report ........................................................
Balance Data ............................................................
List of Materials (Thermoplastic Repair) ....................................
Control Surface Travel and Cable Tension ......... .........................
Troubleshooting Chart (Surface Controls) ...................................
Leading Particulars. Hydraulic Power Pack (Ozone) ..........................
Leading Particulars. Hydraulic Power Pack (Wiebel Tool) .....................
Inspection and Repair. Hydraulic Pump .....................................
Troubleshooting Chart (Hydraulic System) ..................................
Troubleshooting Chart (Landing Gear System) ...............................
Propeller Specifications (PA-31-310 and -325) ................................
Turbocharger Installation Torque Values in Inch-Pounds ......................
Troubleshooting Chart (Engine) and (Turbocharger) ..........................
Propeller Specifications (PA-31-300) .......................................
Propeller Specifications (PA-31-325)........................................
Coupling Torques .......................................................
Troubleshooting Chart (Engine) ............................................
Fuel Quantity Sender Resistance Limits .....................................
Wear Limits for Electric Fuel Pump ........................................
Troubleshooting Chart (Fuel System) .......................................
Deleted
Deleted
Troubleshooting Chart (Instruments) ........................................
Troubleshooting Chart (Pressure System) ....................................
Index - Electrical System Schematics ........................................
Troubleshooting Chart (Electrical System) ...................................
Circuit Load Chart.......................................................
Lamp Replacement Guide.................................................
Component Values to Obtain Balanced Light Output Intensity .................
Electrical Wire Coding ....................................................
Electrical Symbols ........................................................
Index - Electronics Installation Schematics ..................................
Troubleshooting Chart (Heating System) ....................................
IA24
IBII
IC7
IC18
IC21
IC24
ID3
1D4
ID5
ID23
IG6
IH6
1H24
219
2J16
2K I
2K21
2L15
2L19
3B2
3C3
3C13
3E2
3E12
4A 1
4E1
4E8
4E11
4E12
4E13
4E14
5A10
5D14
Revised: 3/2/84 1A15

PIPER NAVAJO SERVICE MANUAL
LIST OF TABLES (cont.)
Table Aerofiche
Grid No.
XIV-I.
XIV-II.
XIV-IIA.
XIV-III.
XIV-IV.
XIV-V.
XIV-VA.
XIV-VI.
XIV-VII.
XIV-VIII.
XI -IX.
XIV-X.
XIV-XI.
Troubleshooting Chart (Oxygen System) ....................................
Troubleshooting Chart (Propeller Deicer System) ......... ....................
Temperature Pressure Chart ...............................................
Aluminum Tubing Torque ......... .......................................
Compressor Oil Charge ...................................................
Belt Tensions (TIO-540-A2C Engine) ........................................
Air Velocity Chart........................................................
Troubleshooting Chart (Air Conditioning) ...................................
Troubleshooting Chart (Engine Synchrophaser) ............................
Troubleshooting Chart (Propeller Synchronizer) ..............................
Operating Pressures .......................................................
Material and Supplies for Cold Repair ......................................
Troubleshooting Chart (Pneumatic Deicer System) ...........................
82 1A16
5E12
5F16
.5G5
5G8
5G20
5G24
5H7
5H12
5I11
5I18
5J2
5J4
5J10
Revised: 1/29/

SECTION I
INTRODUCTION
Paragraph
1-1. General ..................................................................
1-2. Scope of Manual ..........................................................
1-3. Description . ............................................................
1-4. Fuselage .........................................................
1-5. Wing ............................................................
1-6. Empennage .... . . . . . . . ..... .....................
1-7. Flight Controls...................................................
1-8. Hydraulic S stem .................................................
1-9. Landing Gear ....................................................
1-10. Engines and Propellers ............................................
1-11. Fuel System .
1-11. Fuel System ......................................................
1-12. Instruments......................................................
1-13. Electronic Equipment ....................................
1-14. Heating and Ventilating System .....................................
Aerofiche
Grid No.
IA18
1A18
IA18
1A18
1A18
1A18
1A19
1A19
1A19
1A19
1A19
A19
IA 19
1A19
Revised: 11/15/82 1A17

PIPERNAVAJOSERVICEMANUAL
SECTION I
INTRODUCTION
1-1. GENERAL. This manual contains service and maintenance instructions for the Piper PA-31 Navajo,
designed and manufactured as a versatile aircraft in the personal and business avation field, by the Piper
Aircraft Corporation, Lock Haven, Pennsylvania.
1-2. SCOPE OF MANUAL. Sections II and III comprise the service part of this manual. whereas Sections
IV through XIV compnse the maintenance instructions. The service instructions include ground handling,
servicing and inspection. The maintenance instructions for each system include troubleshooting, removal
and installation of components, and corrective maintenance and testing; each major system of the airplane
is covered in a separate section. Only qualified personnel should perform the operations described in this
manual.
The description of the airplane included in this section is limited to general information. Section II
gives leading particulars and principal dimensions, while each major system is described in its appropriate
section of the manual.
1-3. DESCRIPTION. The Piper PA-31 Navajo is a six to eight place, twin engine, low-wingmonoplane of
all metal construction. The following paragraphs provide descriptions of the major components and
systems.
1-4. FUSELAGE. The fuselage is a semi-monocoque structure that consists of three basic units: the nose
section, the cabin section, and the tail cone section.
1-5. WING. The laminar flow wing is of all metal stressed skin, full cantilever design, consisting of two
wing panels bolted together at the center of the fuselage. The wing tips are removable. The ailerons are
cable and push rod controlled and are statically and dynamically balanced. The trailing edge wing flaps are
electrically operated.
1-6. EMPENNAGE. The empennage consists of the vertical stabilizer (fin), rudder with trim tab,
horizontal stabilizer, and elevator with trim tab. The control surfaces are cable controlled, and are
dynamically and statically balanced.
Reissued: 10/12/79 INTRODUCTION
1A18

PIPERNAVAJOSERVICEMANUAL
1-7. FLIGHT CONTROLS. The flight controls are conventional, consisting of dual control wheels that
operate the ailerons and elevator, and dual foot pedals that operate the rudder. The trim tabs for each
control are operated by wheels or knobs located in the control pedestal.
1-8. HYDRAULIC SYSTEM. Two separate hydraulic systems are incorporated in the airplane. The main
system incorporates a hydraulic Power Pack that operates the landing gear and inboard main gear door
actuating cylinders. The second system operates the airplane's brake system.
1-9. LANDING GEAR. The tricycle landing gear system is hydraulically operated and fully retractable
with doors that completely cover the gear when retracted. The gears are air-oil type units.
1-10 ENGINES AND PROPELLERS. The airplane is powered bytwo Avco-Lycoming six cylinder, direct
drive, wet sump, horizontally opposed. fuel injected engines. The propellers are Hartzell full feathering.
constant speed units controlled bya governor mounted on each engine. Referto Section II. Table 11-1.
for all
engine and propeller leading particulars.
1-1
1. FUEL SYSTEM. The fuel system consists of four rubber-type cells located in the wings with a total
fuel capacity of 192 U.S. gallons. Optional 27 gallon Nacelle fuel cells are available for the 31-325.
Incorporated in the system are fuel filters, electric auxiliary fuel pumps, engine driven pumps and a cross feed
system.
1-12. INSTRUMENTS. Provisions for the instrument installation includes panels for engine instruments
and advance flight instruments, as well as space for an optional second set of flight instruments for the
co-pilot. The panel is shock mounted to minimize vibration to the instruments.
1-13. ELECTRONIC EQUIPMENT. Provision for electronic equipment includes various combinations of
radio installations, Auto-Pilot and radar.
1-14. HEATING AND VENTILATING SYSTEM. Heated air for the cabin and defroster is obtained from
a 35,000 B.T.U. Janitrol heater installed in the nose section. Fresh air for the cabin interior is obtained
from two individual sources; one from an intake in the nose section and the other from a scoop located in
the dorsal fin.
Revised: 11/15/82 INTRODUCTION
1A19

SECTION II
HANDLING AND SERVICING
Aerofiche
Paragraph Grid No.
2-1. Introduction ................................................ .. 1A22
2-2. Dimensions .............................................................. 1A22
2-2a. Serial Number Plates ....................................................... 1A22
2-3. Station Reference Lines ....................................................
2-4. Weight and Balance Data ................................................... A2
2-5. Access and Inspection Provisions ............................................ A22
2-6. Tools and Test Equipment .................................................. 1A22
2-7 Torque Requirements ...................................................... 1B13
2-7a. Torque Wrenches .......................................................... 1B13
2-8. Ground Handling .......................................................... B14
2-9. Introduction to Ground Handling ................................... 1B14
2-10. Jacking .......................................................... 1B14
2-11 Weighing ........................................................ 1B14
2-12. Leveling .................................................... .... 1B15
2-13. Mooring ........................................................ 1B16
2-14. Parking .......................................................... 1B16
2-15. Towing .......................................................... B17
2-16. Taxiing .......................................................... IBIS
2-17. External Power Receptacle .................................................. 1B18
2-18. Operation of External Power Receptacle ............................. 1B18
2-19. Servicing ................................................................. 1B18
2-20. General .......................................................... 1B18
2-21. Fuel System .............................................................. B20
2-22. Servicing Fuel System ............................................. B20
2-23. Filling Fuel Cells ................................................. B20
2-24. Draining Moisture from Fuel System ................................ B20
2-25 Draining Fuel System ............................................. 1B20
2-26. Brake System ............................................................ B
2-27. Servicing Brake System ............................................ 1B20
2-28. Filling Brake Cylinder Reservoir .................................... 1B20
2-29. Draining Brake System ............................................ B21
2-30. Oleo Struts ............................................................... 1B21
2-31. Servicing Oleo Struts .............................................. 1B21
2-32. Adding Fluid to Struts ........................... ...... ........ 1B21
2-33. Filling Oleo Struts .................................. ....... ..... B22
2-34. Inflating Oleo Struts .............................................. 1B22
Revised: 3/14/83
1A20