Foreword General California Proposition 65 Warning This manual provides detailed information and procedures to safely repair and maintain the following: WARNING Jacobsen AR-522 rotary mower and associated accessory attachments Certain vehicle components contain or emit This manual is intended to introduce and guide the user chemicals known to the State of California to through the latest factory-approved troubleshooting and cause cancer and birth defects or other...
Near the beginning of each chapter is a specifications listing. This listing contains any specifications contained within the chapter. Copyright 2013, Jacobsen, a Textron Company “All rights reserved, including the right to reproduce this material or portions thereof in any form.” 4181383-Second Edition...
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Table of Contents Safety Electrical Hydrostatic Power Train Hydraulics Steering Cutting Units 4181383-Second Edition...
SAFETY Introduction Safety Notices Safety is the most important element of any repair Throughout this manual, the following key safety words procedure. Knowledge of the procedure to be performed will be used to alert the reader of potential hazards. and safe work habits are essential to preventing death, Become familiar with these words and their meaning.
SAFETY Inspect Safety Labels Use Lifting Equipment Safely Safety decals are critical to the safe operation of the WARNING mower. Inspect the mower for any damaged, missing, or unreadable decals. Replace decals as needed before Always check the lifting capacity and condition of placing the mower back in service.
SAFETY Use Compressed Air and Air Service Tires Safely Tools Safely WARNING WARNING An inflated tire contains explosive force. Use care when handling wheels and tires. Always wear approved eye and ear protection while using compressed air. Misuse of compressed air could result in death or serious •...
SAFETY Handle Fuel Safely Handle Chemical Products Safely Handle fuel with care—it is highly flammable. WARNING WARNING • Never remove the fuel cap from the fuel tank, Exposure to chemical products could result in or add fuel, when the engine is running or serious injury.
SAFETY Service Hydraulic System Safety Service Electrical Components Safely WARNING WARNING The hydraulic system is under pressure, and the oil may be hot! Always disconnect the negative terminal first and • Always allow the machine to cool completely positive terminal last.
ELECTRICAL Specifications Test and Adjustment Specifications Specifications Resistance Across Solenoid Coil—Lift 7.0 ± 10% ohms Solenoid Coil at 68° F (20° C) Resistance Across Solenoid Coil— 6.0 ± 10% ohms Lower Solenoid Coil at 68° F (20° C) Resistance Across Solenoid Coil— 9.8 ±...
ELECTRICAL Theory and Diagnostic Information Electrical Component Symbols The following symbols are used in the electrical schematics to represent various electrical components. Switches Single Pole, Single Throw Double Pole, Single Throw (SPST) (DPST) Single Pole, Double Throw Double Pole, Double Throw (SPDT) (DPDT) Proximity Switch...
ELECTRICAL Miscellaneous Symbols Enclosure Wires (crossing but not (cabinet, housing, etc.) connected) Ground (to earth) Wiring Connections Ground (to chassis) Coil Direct Current (DC) Battery (as shown on an oscilloscope) Alternating Current (AC) Diode (as shown on an oscilloscope) Resistor Pin and Socket Connector 4181383-Second Edition...
ELECTRICAL Electrical Schematic Component Identification Electrical components shown in the main schematic are identified with an alpha-numeric callout. All electrical components shown in the electrical schematic are listed below. • B1—Battery (See Figure 4-1) • SW6—Ignition Switch (See Figure 4-2) •...
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J6-23 108 - Wh 600 - Wh +5V 3 ECU 1-03 Crank +5V J6-40 109 - Rd 626 - Rd Crankshaft ECU 1-42 Crank Sig Sig 2 J6-19 Position Sensor 110 - Bk 627 - Bk Gnd 1 ECU 1-43 Crank Ground J6-24 111 - Gn...
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507 - Ye 507 - Ye V CAN H ECU 2-30 508 - Gn 508 - Gn V CAN L ECU 2-42 526 - Gn 526 - Gn Park Regen Sw ECU 2-28 525 - Bn/Ye 525 - Bn/Ye Regen Inhibit ECU 2-39 514 - Bu 514 - Bu...
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Vehicle CAN 11-A 507 - Ye 507 - Ye Diagnostic 11-B 508 - Gn 508 - Gn Connector 526 - Gn 507 - Ye MCU J1-08 V CAN H 525 - Bn/Ye 508 - Gn MCU J1-09 V CAN L 514 - Bu 514 - Bu MCU J4-05...
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518 - Gy/Og 518 - Gy/Og 20 - Bk Right Wing Lift/Lower MCU J2-02 SOL1 (722 Only) 517 - Gn 517 - Gn 20 - Bk Left Wing Lift/Lower MCU J2-11 SOL2 (722 Only) 20 - Bk 516 - Bu 516 - Bu Wing Lift Main MCU J2-12...
Theory of Operation and Sub • Inhibit/Regen Switch (SW16) terminals (2) and (5) • Glow Plug Light (L4) Circuit Schematics • Check Engine Light (L8) • Park Regen Light (L4) Power Circuit—Theory of Operation • Traction Control Switch (SW14) Unswitched Power Circuit •...
Power Circuit Schematic See figures 4-3 and 4-4. Switched Power Circuit J6-23 108 - Wh 600 - Wh +5V 3 ECU 1-03 Crank +5V J6-40 Main Relay Circuit 109 - Rd 626 - Rd Crankshaft Sig 2 ECU 1-42 Crank Sig J6-19 Position Sensor 110 - Bk...
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Power Circuit Schematic (Continued) 507 - Ye 507 - Ye V CAN H ECU 2-30 508 - Gn 508 - Gn V CAN L ECU 2-42 526 - Gn 526 - Gn Park Regen Sw ECU 2-28 525 - Bn/Ye 525 - Bn/Ye Regen Inhibit ECU 2-39...
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Power Circuit Schematic (Continued) Vehicle CAN 11-A 507 - Ye 507 - Ye Diagnostic 11-B 508 - Gn 508 - Gn Connector 526 - Gn 507 - Ye MCU J1-08 V CAN H 525 - Bn/Ye 508 - Gn MCU J1-09 V CAN L 514 - Bu 514 - Bu...
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Power Circuit Schematic (Continued) 518 - Gy/Og 518 - Gy/Og 20 - Bk Right Wing Lift/Lower MCU J2-02 SOL1 (722 Only) 517 - Gn 517 - Gn 20 - Bk Left Wing Lift/Lower MCU J2-11 SOL2 (722 Only) 20 - Bk 516 - Bu 516 - Bu Wing Lift Main...
Charging Circuit—Theory of Operation Power Circuit (See “Power Circuit—Theory of Operation” on page 2-16.) Charging Circuit With the engine running and the ignition switch (SW6) in the run position, voltage at the alternator (U22) terminal (S) excites the alternator. With the alternator (S) terminal excited, the alternator produces three-phase alternating current (AC).
Start and Glow Plug Circuit—Theory Unswitched power is supplied from the battery (B1) positive terminal to the starting motor (M1) battery of Operation terminal, and to the battery terminal of the 50A circuit breaker (CB1). Mower Controller (MCU) 90 - Og/Wh MCU J1-03 Ign On Ignition Switch...
From the battery terminal of the 50A circuit breaker (CB1) Start and Glow Plug Circuits unswitched power is also supplied to the following To start and operate the engine with the operator on or components: off the seat, the mow switch (SW8) must be in the off •...
Run Circuit—Theory of Operation terminal, and to the battery terminal of the 50A circuit breaker (CB1). Unswitched Power Circuit 523 - Wh/Rd 523 - Wh/Rd Run - Interlock ECU 2-26 260 - Bn/Rd 260 - Bn/Rd Park Brake Sw ECU 2-19 260 - Bn/Rd SW13 Parking Brake Switch...
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From the battery terminal of the 50A circuit breaker (CB1) • 20A Fuse (F6) (internal to MCU) unswitched power is also supplied to the following • 20A Fuse (F7) (internal to MCU) components: • 25A Fuse (F2) 523 - Wh/Rd 523 - Wh/Rd MCU J2-07 Run - Interlock...
Switched Power Circuit The ECU (U18) will un-ground the main circuit relay approximately 1 second after the seat switch (SW5) When the ignition switch (SW6) is turned to the run contacts open. The time delay is to compensate for seat position, current flows from ignition switch terminal (4) to bounce when operating the machine over rough terrain.
Lift/Lower Circuit—Theory of page 2-16.) Operation 523 - Wh/Rd 523 - Wh/Rd Run - Interlock ECU 2-26 260 - Bn/Rd 260 - Bn/Rd Park Brake Sw ECU 2-19 260 - Bn/Rd 90 - Og/Wh SW13 Parking Brake Switch Unswitched Power Circuit Switched Power Circuit Main Relay Circuit Engine Controller...
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Lift Circuit (J3-05) to the 5 gang lift solenoid (SOL6), energizing the solenoid.** With the solenoid energized, the cutting units When the joystick (SW9) is placed in the lift position, 523 - Wh/Rd 523 - Wh/Rd MCU J2-07 Run - Interlock 260 - Bn/Rd 260 - Bn/Rd MCU J4-09...
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**In addition, on AR-722 models, current also flows from MCU terminal (J2-12) to the wing lift main solenoid NOTE (SOL3), energizing the solenoid. With the solenoid energized, the cutting units will rise until they reach their While mowing, the lift/lower function will be in “one-touch end of travel.
Mow Circuit—Theory of Operation With the left cross cut switch (SW2) input activated and the right wing lift/lower switch (SW10) input activated, current flows from VCU terminal (J2-10) to the right wing Power Circuit mow solenoid (SOL9), energizing the solenoid. (See “Power Circuit—Theory of Operation”...
Float/Traction Control Circuit— (See “Power Circuit—Theory of Operation” on page 2-16.) Theory of Operation 518 - Gy/Og 518 - Gy/Og 20 - Bk Right Wing Lift/Lower MCU J2-02 SOL1 (722 Only) 517 - Gn 517 - Gn 20 - Bk Left Wing Lift/Lower MCU J2-11 SOL2...
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Float/Traction Control Circuit When the mow 5 gang mow switch (SW8) is in the mow position, the traction control circuit operates automatically. (See “Mow Circuit—Theory of Operation” on page 4-20.) When the mow switch (SW8) is in the mow position, current flows to MCU (U18) terminal (J3-10), activating the input.
Instrumentation Circuit—Theory of Operation Power Circuit Hydraulic Oil Level Light (See “Power Circuit—Theory of Operation” on When the hydraulic level switch (SW17) closes, current page 2-16.) flows to the MCU (U18) terminal (J4-12). Current then flows from MCU terminal (J2-05) to the combination Combination Gauge gauge (U21) terminal (C) turning on the indicator light The combination gauge (U21) displays operating hours...
Engine Temperature Light The temperature sender (U7) resistance changes in relationship to the engine coolant temperature. As the temperature sender is heated, the resistance of the sensor changes from a high resistance to a low resistance. The voltage drop across the temperature sender is provided to the ECU (U1) terminal (1-19).
Horn and Light Circuit— page 2-16.) Theory of Operation 523 - Wh/Rd 523 - Wh/Rd Run - Interlock ECU 2-26 260 - Bn/Rd 260 - Bn/Rd Park Brake Sw ECU 2-19 Temp Sender 90 - Og/Wh 260 - Bn/Rd J6-38 SW13 106 - Wh 610 - Wh...
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Horn Circuit The MCU can also activate the horn as a test or signal for various issues. See “Start and Glow Plug Circuit-Theory When the horn switch (SW7) is placed in the on position, Fuel Filter Circuit Unswitched Power Circuit Throttle Position Circuit Switched Power Circuit 523 - Wh/Rd...
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Light Circuit Current flows from the MCU (U18) to the light switch (SW12) When the light switch is in the on position, voltage is provided to the right (L1) and left (L2) head lights, turning on the lights. Horn and Headlight Circuit Schematic See Figures 4-15 Active Regen and Park Regen Circuits—...
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Park Regen Circuit Schematic See Figure 4-7 Mower Controller (MCU) Unswitched Power Circuit Switched Power Circuit 90 - Og/Wh Headlight Circuit MCU J1-03 Ign On Horn Circuit Ignition Switch 360 - Pk/Bk 50 - Rd Horn MCU J3-06 Horn Switch 70 - Og/Ye 20 - Bk MCU J1-04...
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Park Regen Circuit Schematic See Figure 4-7 Active Regen Circuit Schematic See Figures 4- Active Regen Circuit Schematic See Figures 4- 2-48 4181383-Second Edition...
Troubleshooting Symptom: MCU does not power up. Probable Cause Remedy Open fuse 20A fuse F6. Test fuse. (See “Fuse Test” on page 2-54.) Faulty MCU (U18) unswitched power Measure voltage between MCU (U18) terminal (J3-6) and ground. circuit. Voltage must be approximately 12 VDC. Faulty MCU (U18) switched power circuit.
Charging Circuit Symptom: Battery not charging. Probable Cause Remedy Faulty alternator (U22) output circuit. Make sure alternator (U22) output cable and battery positive (+) cable terminals are clean and tight. Check continuity between starter battery terminal and battery positive (+) terminal. Continuity must be indicated.
Start Circuit Symptom: Starter motor solenoid does not engage. Probable Cause Remedy Parking brake switch (SW13) is in the off Place the parking brake switch (SW13) in the on position. position. Traction pedal not in the neutral position. Move the traction pedal to the neutral position. Mow switch (SW8) is in the mow position.
Lift/Lower Circuit Symptom: Lower solenoid does not energize. Probable Cause Remedy Faulty joystick (SW9). With the joystick (SW9) in the lower position, check MCU (U18) joystick lower switch LED. If the LED does not light, test the switch. (See “Joystick Test” on page 2-55.) Faulty switched power circuit.
Mow Circuit Symptom: Mow solenoid does not energize. Probable Cause Remedy Joystick (SW9) was not momentarily Momentarily place the joystick (SW9) in the lower position to activate the cutting units. placed in the lower position. Faulty Mow switch(SW8). With the mow switch (SW8) in the on position, check MCU (U18) mow switch input LED. If the LED does not light, test switch.
Instrumentation Circuit Lamp and Audible Alarm Check Circuit The MCU provides a lamp and audible alarm check circuit. When the ignition switch is turned to the run position the MCU turns on the following for approximately 3 seconds: • Glow Plug Light •...
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Symptom: Hydraulic filter pressure light does not turn on with a blocked filter. Probable Cause Remedy Faulty MCU (U18) output circuit. With the ignition switch (SW6) in the run position, check MCU (U18) hydraulic filter lamp output LED. If the LED turns on for approximately 3 seconds, check for continuity between hydraulic filter pressure light Pur/Grn wire terminal at combination gauge (U21) and MCU (U18) hydraulic filter pressure light output terminal (J2-8).
Symptom: Engine temperature light does not light during lamp and audible alarm check. Probable Cause Remedy Faulty temperature sender (U7). With a jumper wire, connect the temperature sender (U7) to ground. With the ignition switch (SW6) in the run position, check the light. If the light is on, replace the temperature sender.
Symptom: Horn does not sound with engine temperatures over 230° F (110°C). Probable Cause Remedy Faulty temperature sender (U7) input Check continuity between temperature sender (U7) DG wire terminal and MCU (U18) circuit. temperature sender input terminal J2-12. Continuity must be indicated. Light Circuit Symptom: Head lights do not turn on.
Component Testing 6. Test the function of the circuit. Does the circuit now operate properly? Electrical System and Component Replace the wire. Testing Continue testing other wires and components in the circuit. General Information Resistance Test Repair of the electrical system, for the most part, is limited to the replacement of defective components or Required Tools or Equipment wiring.
Fuse Test Plug-In Fuses See Figure 2-1. Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove fuse from fuse holder. (See “Plug-In Fuses” on page 2-66.) TN5138 Figure 2-2 3.
Ignition Switch Test Joystick Test See Figure 2-3. See Figure 2-4. Required Tools or Equipment Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on 1.
5. Check for continuity. 5. With the test leads still connected, press the traction control switch. Is continuity indicated? Is continuity indicated? Proceed to step 6. The switch is good. The switch is faulty; replace the lift-lower switch assembly. The switch is faulty; replace the switch. 6.
Light Switch Test Horn Switch See Figure 2-6. See Figure 2-7. Required Tools or Equipment Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on 1.
Parking Brake Switch Seat Switch Test See Figure 2-8. See Figure 2-9. Required Tools or Equipment Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on 1.
Hydraulic Level Switch Test See Figures 2-10 and 2-11. Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Check to make sure hydraulic oil is at the correct level.
Solenoid Test See Figure 2-14. Required Tools or Equipment Digital Multimeter or Ohmmeter 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) NOTE This procedure applies to the following solenoid coils: • Mow Solenoid TN5250 • Lift Solenoid Figure 2-12 •...
Hydraulic Filter Pressure Switch Test See Figure 2-15. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Shut down the engine and remove the key. 3. Set the multimeter to the continuity setting. TN5217 Figure 2-16 3.
Circuit Breaker Test See Figure 2-18. Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Allow engine to cool completely. 3. Set the multimeter to 20 volts DC. 4.
Fuel Pump Test See Figures 2-19 and 2-20 Required Tools or Equipment Digital Multimeter, Ohmmeter, or Continuity Tester 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Allow engine to cool completely. TN1617 Figure 2-20 6. Using a jumper wire (1), connect one end to the power wire (2) pump side.
Repair NOTICE Battery and Battery Tray Never place used batteries in the garbage. Dispose of used batteries in accordance with all applicable regulations. Removal and Installation See Figures 2-21 and 2-22. 6. Remove battery (9). WARNING • Battery posts, terminals, and related accessories contain lead and lead compounds.
Alternator Removal and Installation See Figures 2-23 and 2-24. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Raise the hood. 3. Disconnect the negative (–) battery cable at the battery. 12 13 TN1455 Figure 2-24 7.
Plug-In Fuses Removal and Installation See Figures 2-27 and 2-28. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Raise the hood. 3. Disconnect the negative (–) battery cable at the battery. TN1454 Figure 2-25 4. Remove boot (5) from terminal, and slide it down the wire (3).
Circuit Breaker 6. Remove nuts (7), and disconnect wires (2). 7. Remove two nuts (5) and screws (6). Removal and Installation 8. Remove circuit breaker (8). See Figures 2-29 and 2-30. NOTE 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) Install plug-in fuse(s) by reversing the order of removal.
TN1458 TN1458 Figure 2-34 Figure 2-32 5. Pull the relay (3) straight up and out of the relay base 5. Pull the relay (3) straight up and out of the relay base (4). (4). Installation Note Installation Note Install the glow plug relay by reversing the order of Install the starter relay by reversing the order of removal.
TN5231 TN5252 Figure 2-35 Figure 2-36 NOTES 4. Disconnect wiring connector (1) from ignition switch. • Seat removed for photo clarity. • If moving the instrument panel aside, use caution to prevent stretching or kinking the cables. 4. Remove six screws (1) and move the panel (2) aside, to allow servicing of components as needed.
Rocker Switches See Figure 2-38. TN5255 Figure 2-39 NOTE TN5254 Figure 2-38 Label all wires before disconnecting to ensure correct installation. This procedure applies to the following switches: 4. Disconnect wire connectors (5). • Traction Control Switch (4) 5. Depress tabs (6) on each side of the rocker switch •...
Removal and Installation See Figures 2-41 and 2-42. NOTE Glow plug indicator lamp shown. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Disconnect the negative (–) battery cable at the battery. 3. Remove instrument panel. (See “Instrument Panel” on page 2-68.) TN5258 Figure 2-42...
Neutral Switch NOTE Label all wiring connectors and note their orientation of Removal and Installation the joystick before removing to ensure correct See Figures 2-45 and 2-46. installation. 1. Park the mower safely. (See “Park Mower Safely” on 4. Disconnect the joystick wiring connector (1) from the page 1-5.) wiring harness connector (2).
Solenoid Coils This procedure applies to the following solenoid coils: • Mow Solenoid Coil (1) See Figures 2-47 through 2-49. • Lift Solenoid Coil (2) • Lower Solenoid Coil (3) • Park Brake Solenoid (4) The mow solenoid coil is located under right center of machine.
Hydraulic Oil Filter Switch Installation Notes • Clean cartridge of any debris or surface rust and Removal and Installation apply dielectric grease (Jacobsen PN 365422) to cartridge before installation. See Figure 2-52. • Install solenoid coils by reversing the order of ...
Installation Notes Installation Notes Required Materials Required Materials ® ® Telfon Tape Telfon Tape • Install hydraulic filter switch by reversing the order of • Install engine oil pressure switch by reversing the removal. order of removal. ® ® • Apply Teflon tape to the threads of the hydraulic •...
Installation Notes Required Materials ® Telfon Tape • Install temperature sender by reversing the order of removal. ® • Apply Teflon tape to the threads of the temperature sender before installing. Removal and Installation See Figures 2-55 through 2-57. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) TN5417 2.
Combination Gauge Fuel Level Sender Removal and Installation Removal and Installation See Figure 2-58. See Figure 2-59. 1. Park the mower safely. (See “Park Mower Safely” on 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) page 1-5.) 2.
Horn Removal and Installation See Figure 2-60. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Disconnect the battery negative (–) cable at the battery. 3. Remove instrument panel. (See “Instrument Panel” on page 2-68.) TN5267 Figure 2-60 NOTE Label all wires before disconnecting to ensure correct...
HYDROSTATIC POWER TRAIN Hydraulic Hose, Tube, and Fitting Replacement O-Rings for ORS (Face Seal) Fittings General Instructions Jacobsen O-Ring Installation ORS (Face Seal) ORS (Face Seal) Part Tube Size O-Ring Size Number • Always install new O-rings. • On hoses with O-ring fittings, make sure O-rings are 339908 properly seated before tightening.
HYDROSTATIC POWER TRAIN Hydraulic Service Tools Hydraulic Hose Installation Hold the fixed portion of the hose coupling with one NOTE wrench; use a second wrench to tighten or loosen the hose nut. This will avoid damaging the fitting seal. When The hydraulic service tools listed here can be obtained tightening a hose, do not permit the hose to twist;...
HYDROSTATIC POWER TRAIN Digital Hydraulic Tester Hydraulic Flow Meter Part Number AT40031 Part Number AT40002 TN4287 Figure 3-5 Features • Glycerin filled pressure gauge • Precision needle-type load valve • 4–40 gpm (15–15 lpm) flow range TN4288 Figure 3-4 • Pressure up to 5000 psi (345 bar) •...
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HYDROSTATIC POWER TRAIN Hydraulic Hose Kit This blocking disk set is part of the JAC5001A Hydraulic Test Fitting Kit. Part Number JAC5001H Contents NOTE • Two -6 blocking disks This hydraulic hose kit is intended to be used with the •...
HYDROSTATIC POWER TRAIN Component Location See Figure 3-8. TN5269, TN5268, TN5243 Left Rear Wheel Motor 4WD Valve Right Rear Wheel Motor Hydrostatic Pump Left Front Wheel Motor Traction Pedal Right Front Wheel Motor Figure 3-8: Power Train Component Location 4181383-Third Edition...
HYDROSTATIC POWER TRAIN Theory of Operation and Hot Oil Shuttle Sub-Circuit Schematics The hot oil shuttle is located in the 4WD valve. The hot oil shuttle is held open when there is operating pressure oil in the forward direction. Charge pressure oil returning Traction Circuit Forward Schematic from the rear wheel motors flows through a 0.040-inch and Theory of Operation...
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HYDROSTATIC POWER TRAIN Traction Circuit—Forward Schematic See Figures 3-9 and 3-10. 4350 psi Tow Valve 2.81 ci .85 ci 2920 RPM 0.88 ci 0.5 ci 0.88 ci 3625 psi Gear Pump Displacement Control Valve Drain 0.31” 285 psi Supply 0.28” Hydrostatic Traction Pump...
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HYDROSTATIC POWER TRAIN Right Front Wheel Motor 24.287 ci Left Front 24.287 ci Wheel Motor 400 psi Valve 400 psi Hot Oil Shuttle Valve 0.040 18.7 ci 18.7 ci Right Rear Left Rear Wheel Wheel 350 psi Motor Motor From T Port Steering Valve Brake Release...
HYDROSTATIC POWER TRAIN Traction Circuit Reverse Schematic and Theory of Operation System Conditions: • Engine running • Park brake released • Traction pedal depressed (reverse position) • Tow valve in “Brake Engaged” position Charge Pressure Circuit The charge pump and traction pump are both driven by the engine.
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HYDROSTATIC POWER TRAIN Traction Circuit—Reverse Schematic See Figures 3-11 and 3-12. Tow Valve Gear Pump 4350 psi 2.81 ci 2920 RPM 5.47 ci 0.5 ci 0.88 ci 0.88 ci 3625 psi Drain 0.31” Displacement Supply 0.28” Control Valve Hydrostatic Traction Pump 285 psi Return Oil...
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HYDROSTATIC POWER TRAIN Right Front Wheel Motor Left Front Wheel Motor 400 psi Valve 400 psi Hot Oil Shuttle Valve 0.040 18.7 ci 18.7 ci Right Rear Left Rear Wheel Wheel 350 psi Motor Motor From T Port Steering Valve Brake Release Valve...
HYDROSTATIC POWER TRAIN Troubleshooting Mower Will Not Move Forward or Reverse Probable Cause Remedy Hydraulic oil not at correct level in reservoir. Fill reservoir to correct level. (Refer to “Parts and Maintenance Manual” for correct oil specifications.) Tow valve open. Close tow valve.
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HYDROSTATIC POWER TRAIN Mower Moves When Traction Pedal Is in Neutral Probable Cause Remedy Traction pump neutral not properly adjusted. Adjust traction linkage. (See “Adjust Transmission Neutral (Creep)” on page 3-17.) Hydrostatic System Operating Hot Probable Cause Remedy Hydraulic oil not at correct level in reservoir. Fill reservoir to correct level.
HYDROSTATIC POWER TRAIN Tests and Adjustments WARNING Transmission Neutral Adjustment Never operate the engine without proper ventilation; exhaust fumes can be fatal if inhaled. Adjust Transmission Neutral (Creep) See Figures 3-13 and 3-14. CAUTION 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) Engine component will become hot during 2.
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HYDROSTATIC POWER TRAIN TN1702 Figure 3-14 21. Remove control spool (6) as an assembly. Clean and WARNING inspect. Never operate the engine without proper NOTE ventilation; exhaust fumes can be fatal if inhaled. Control sleeve (7) may be difficult to remove. If needed, use a blind race puller with a slide hammer to remove.
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HYDROSTATIC POWER TRAIN 36. Stop the engine and apply brake. 37. Repeat the procedure if any wheel movement is noted. 38. Install and connect all components as noted prior to adjustment. Adjust Traction Pedal Neutral Switch See Figure 3-15. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2.
HYDROSTATIC POWER TRAIN Field Test Procedures When a hydraulic system failure occurs, some simple effective tests can be performed prior to using a test instrument. The results of these tests can lead you to the suspected component failure. More extensive test procedures, using test instruments, are presented later in this section.
HYDROSTATIC POWER TRAIN Wheel Motor Test The wheel motor case drain is used to return lubrication oil or bypassed hydraulic oil to the hydraulic tank. 1. Operate hydraulic system until oil temperature is at 120–150° F (49–65° C). 2. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 3.
HYDROSTATIC POWER TRAIN Instrument Test Procedures Calculations: System Test Instrument Test Overview No Load Flow = 10.0 gpm The following tests are specifically designed to approach Loaded Flow = 7.6 gpm hydraulic testing on a system level. Each component 10.0 – 7.6 / 10.0 x 100 = Total System Leakage 24% within the system represents a portion of the total system leakage.
HYDROSTATIC POWER TRAIN Charge Pressure Test See Figures 3-17 through 3-20. WARNING The hydraulic system is under pressure, and the oil will be hot. • Always relieve pressure in the hydraulic system before performing service. • Failure to follow appropriate safety precautions may result in death or serious injury.
HYDROSTATIC POWER TRAIN Traction System Test See Figures 3-21 through 3-25. IMPORTANT • This test works together with the wheel motors test to isolate a problem within the hydrostatic power train. • Performing this test will isolate the traction pump and front wheel motors from the rest of the hydrostatic system.
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HYDROSTATIC POWER TRAIN TN1705 Figure 3-23 7. Install flow lock tool (1) and secure to pump control arm. 8. Close tow valve completely by turning clockwise. TN5475 Figure 3-22: Traction System Test—Install TN5407 Wheel Restraints to Front Wheels Figure 3-24 9.
HYDROSTATIC POWER TRAIN 23. Calculate traction system leakage. (Step 20 – Step 21 / Step 20 x 100 = Leakage Percentage) Is traction system leakage 10% or less? The traction system is good. Additional testing is required. Proceed to “Wheel Motors Test”...
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HYDROSTATIC POWER TRAIN NOTE Verify engine rpm is within specification (2920 ± 50 rpm) to ensure accurate hydraulic test results. 5. Start engine, release brake, and run at full throttle (2920 ± 50 rpm). TN1357 Figure 3-26 3. Install blocking disks at locations (1 and 3). TN1705 Figure 3-28 6.
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HYDROSTATIC POWER TRAIN 24. Stop engine, apply brake, and return flow lock tool to CAUTION neutral position. Is forward system relief pressure 4350 psi Do not exceed 4350 psi (300 bar) when testing (300 bar)? system relief valves or equipment damage may occur.
HYDROSTATIC POWER TRAIN Wheel Motors Test See Figures 3-29 through 3-40. IMPORTANT • This test works together with the traction system test to isolate a problem within the hydrostatic power train. • Performing this test will isolate the wheel motors and 4WD valve from the rest of the hydrostatic system.
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HYDROSTATIC POWER TRAIN 8. Start engine, release brake, and run at full throttle (2920 ± 50 rpm). TN1705 Figure 3-32 9. Adjust flow lock tool (3) to allow pump to produce 15 gpm (57 lpm) in the forward direction. 10. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 2000 psi (138 bar) or one-half of the relief valve rating is reached.
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HYDROSTATIC POWER TRAIN WARNING Prevent personal injury. Use properly rated lifting devices. Always be sure load is balanced before lifting. Support the machine properly using jackstands. IMPORTANT It is important to lift and support the front of machine, or the machine will move. 16.
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HYDROSTATIC POWER TRAIN 23. Slowly close flow meter valve until pressure reaches 2700 psi (186 bar). Read and record loaded flow. 24. Stop engine, apply brake, and return flow lock tool to neutral position. 25. Calculate left check valve leakage. (Step 12 –...
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HYDROSTATIC POWER TRAIN 34. Stop engine, apply brake, and return flow lock tool back to neutral position. 35. Calculate left rear wheel motor leakage. (Step 23 – Step 33 / Step 23 x 100 = Leak Percentage) Is left rear wheel motor leakage 10% or less? The left rear wheel motor is good.
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HYDROSTATIC POWER TRAIN NOTE Verify engine rpm is within specification (2920 ± 50 rpm) to ensure accurate hydraulic test results. 41. Start engine, release brake, and run at full throttle (2920 ± 50 rpm). 42. Adjust flow lock tool (3) to allow pump to produce 15 gpm (57 lpm) in the forward direction.
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HYDROSTATIC POWER TRAIN NOTE Verify engine rpm is within specification (2920 ± 50 rpm) to ensure accurate hydraulic test results. 52. Start engine, release brake, and run at full throttle (2920 ± 50 rpm). 53. Adjust flow lock tool (3) to allow pump to produce 15 gpm (57 lpm) in the forward direction.
HYDROSTATIC POWER TRAIN 67. Stop engine, apply brake, and return flow lock tool to WARNING neutral position. 68. Calculate right rear wheel motor leakage. Prevent personal injury. Use properly rated lifting (Step 56 – Step 66 / Step 56 x 100 = Leak devices.
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HYDROSTATIC POWER TRAIN NOTE Verify engine rpm is within specification (2920 ± 50 rpm) to ensure accurate hydraulic test results. 6. Start engine, release brake, and run at full throttle (2920 ± 50 rpm). 7. Operate hydraulic system until oil temperature is at 120–150°...
HYDROSTATIC POWER TRAIN Repair Drive Shaft Removal and Installation See Figure 3-44. TN5170 Figure 3-44 1. Park the mower safely. (See “Park Mower Safely” on Installation Notes page 1-5.) • Install drive shaft by reversing the order of removal. 2. Remove lock nut (1), lock washer (2), and screw (11). •...
HYDROSTATIC POWER TRAIN Traction Pump 7. Remove lock nut (6), lock washer (7), and screw (9). 8. Disconnect drive shaft (5) from traction pump input Removal and Installation shaft (8). See Figures 3-45 through 3-50. 9. Support the drive shaft (5) using a suitable lifting device.
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HYDROSTATIC POWER TRAIN Installation Notes WARNING • Install the traction pump by reversing the order of removal. The traction pump weighs approximately 131 lb • Ensure new O-rings are in place before installing (59 kg). Prevent personal injury. Use a properly hoses on fittings.
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HYDROSTATIC POWER TRAIN Disassembly, Inspection, and Assembly See Figures 3-51 and 3-52. TN1394 Relief Valve Cylinder Block Kit Ring Bypass Valve Pump Shaft Roller Bearing Charge Pressure Relief Valve Ring Plug Variable Swash Plate Retaining Ring Front Cover Gasket Journal Bearing Shaft Seal Needle Bearing Screw...
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HYDROSTATIC POWER TRAIN TN1393 Screw O-Ring Piston Screw Plug Piston Ring Kit Washer Flange Cover O-Ring Control Handle Flange Plug Screw Pad Adapter Snap Ring Servo Cover Gasket Neutral Bracket Temper Load Ring Spring Servo Cover Screw O-Ring Screw Screw (5) Plug Plug Plug...
HYDROSTATIC POWER TRAIN 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove traction pump. (See “Traction Pump” on page 3-39.) 3. Disassemble traction pump as shown in Figure 35. 4. Place parts in assembly order on a clean work area as they are removed.
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HYDROSTATIC POWER TRAIN Disassembly, Inspection, and Assembly NOTICE See Figures 3-55 and 3-56. It is important that all pump parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages.
HYDROSTATIC POWER TRAIN 4WD Valve Removal and Installation See Figure 3-57. TN1511, TN5409 Figure 3-57 1. Park the mower safely. (See “Park Mower Safely” on 3. Disconnect hoses (1–5). page 1-5.) 4. Disconnect hoses (7–10). 2. Drain hydraulic tank. 5. Remove mounting screws, flat washers, and lock washers (11).
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HYDROSTATIC POWER TRAIN Installation Notes NOTICE • Install 4WD valve by reversing the order of removal. • Ensure new O-rings are in place before installing It is important that all component parts are hoses on fittings. absolutely clean, as contamination can result in serious damage and/or improper operation.
HYDROSTATIC POWER TRAIN Front Wheel Motor Removal and Installation See Figures 3-60 and 3-61. TN5393 Figure 3-60 1. Park the mower safely. (See “Park Mower Safely” on 6. Support the wheel motor using a suitable lifting page 1-5.) device. 2. Remove front wheel. (See “Front Wheels” on 7.
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HYDROSTATIC POWER TRAIN Brake Mandrel Bolt and Nut See Figure 3-62. Required Tools or Equipment Brake Mandrel Bolt and Nut TN4667 M12 x 150 mm Bolt Hh12 Nut TN5172 Class 10.9 Threaded Full Length Figure 3-61 Figure 3-62: Brake Mandrel Bolt and Nut 8.
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HYDROSTATIC POWER TRAIN Bearing Support and Sealing Ring Mandrel Bearing Support Snap Ring See Figure 3-64. Installation/Removal Tool See Figure 3-66. Required Tools or Equipment Required Tools or Equipment Bearing Support and Sealing Ring Mandrel Bearing Support Snap Ring Installation/Removal Tool TN4672 4.33 in.
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HYDROSTATIC POWER TRAIN Disassembly and Inspection See Figures 3-67 through 3-75. TN4693 Motor Shaft Rotational Group O-Ring Snap Ring Environmental Seal Stud (5) Backup Ring Spring Washer Roller Bearing Valving Brake Shaft Screw (10) Bearing Support Seal Ring External Brake Discs (21) Brake Housing Radial Lip Seal (with Spring) Seal Ring...
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HYDROSTATIC POWER TRAIN Brake Disassembly First Method with a Mandrel and Bolt TN4680 Figure 3-69 a. Install the brake spring washer compression mandrel onto spring washer (35). (See “Brake Mandrel Bolt and Nut” on page 3-48.) TN4682 b. Lubricate the brake mandrel bolt threads and nut Figure 3-68 faces and tighten the brake mandrel bolt into brake piston (32) down to the thread root.
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HYDROSTATIC POWER TRAIN 5. Remove snap ring (34), spring washer (35), and brake piston (32). 6. Remove and discard O-ring (31). 7. Remove and discard ten screws (36) and remove brake housing (37). NOTE When removing shims (28), mark the mounting order of the shims and note the quantity and total thickness of shims.
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HYDROSTATIC POWER TRAIN 24. Release press force and remove mandrel. NOTE When removing shim spacer (7), measure and note the thickness of the shim spacer. 25. Remove shim spacer (7). TN4696 Figure 3-74 26. Place bearing support (4) on blocks (51) under a press (50) with enough clearance to remove motor shaft (1).
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HYDROSTATIC POWER TRAIN Front Wheel Motor Assembly See Figures 3-76 through 3-85. TN4693 Motor Shaft Rotational Group O-Ring Snap Ring Environmental Seal Stud (5) Backup Ring Spring Washer Roller Bearing Valving Brake Shaft Screw (10) Bearing Support Seal Ring External Brake Discs (21) Brake Housing Radial Lip Seal (with Spring) Seal Ring...
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HYDROSTATIC POWER TRAIN Motor Assembly 11. Lubricate lips of environmental seal (2) with Mobilux EP2 grease. NOTICE 12. Position motor shaft (1) under a press to avoid any force on the studs. • It is important that all component parts are 13.
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HYDROSTATIC POWER TRAIN 19. Lubricate O-ring (11) with Mobilux EP2 grease and install O-ring in valving cover (18). NOTE There are three different size seal rings and backup rings. Install the smallest seal ring to the deepest groove first. 20. Install seal rings (15–17) in valving cover (18), smallest first.
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HYDROSTATIC POWER TRAIN NOTE IMPORTANT Make sure alignment of timing notch in valving (14) and After degreasing with isopropyl alcohol, do not touch locating pin in valving cover (18) is maintained when the mating surfaces of the valving cover and brake installing valving cover.
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HYDROSTATIC POWER TRAIN IMPORTANT The glued connection remains fragile up to six hours after being glued. During this time, avoid any shock to the glued parts; do not use or test the brake or the wheel motor. 42. Place brake housing onto valving cover and install ten new screws (36).
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HYDROSTATIC POWER TRAIN TN4694 Figure 3-85 50. Install brake piston (32) in brake housing (37). 51. Lubricate spring washer (35) with Mobilux EP2 grease and install spring washer on brake piston (32). 52. Compress spring washer (35) by one of the two methods described in Front Wheel Motor “Disassembly and Inspection”...
HYDROSTATIC POWER TRAIN Rear Wheel Motor Removal and Installation See Figures 3-86 through 3-89. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove rear wheel. (See “Rear Wheels” on page 9-10.) NOTES • Label all hydraulic hoses before disconnecting to ensure correct installation.
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HYDROSTATIC POWER TRAIN 16 17 16 17 TN5399 Figure 3-89 13. Remove four screws (16) and lock washers (17). 14. Remove motor (14) from motor mount (15). Installation Notes Required Materials Anti-Seize Compound • Install rear wheel motor by reversing the order of removal.
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HYDROSTATIC POWER TRAIN Disassembly, Inspection, and Assembly See Figures 3-90 and 3-91. TN1539 Dust Seal Wear Plate Valve Drive Plug Bearing Housing Seal Valve Plate Outer Face Seal Seal Ring Drive Balance Ring Backup Ring Geroler Spring Valve Shaft Seal Shaft Seal Valve Housing Screw (4) Seal...
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HYDROSTATIC POWER TRAIN Rear Wheel Motor Timing NOTICE It is important that motor parts are marked and placed in assembly order to aid in assembly. It is important that all motor parts are absolutely clean, as contamination can result in serious damage and/or improper operation.
HYDRAULICS Hydraulic Hose, Tube, and Fitting Replacement O-Rings for ORS (Face Seal) Fittings General Instructions Jacobsen O-Ring Installation ORS (Face Seal) ORS (Face Seal) Part Tube Size O-Ring Size Number • Always install new O-rings. • On hoses with O-ring fittings, make sure O-rings are 339908 properly seated before tightening.
HYDRAULICS Hydraulic Service Tools Digital Hydraulic Tester Part Number AT40031 NOTE The hydraulic service tools listed here can be obtained from K-Line Industries at http://klineind.com. Portable In-Line Filter Part Number JAC5097 TN4288 Figure 4-4 Features • Flow up to 100 gpm (379 lpm) TN4286 •...
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HYDRAULICS Digital Pressure Gauge Kit Hydraulic Test Fitting Kit Part Number JAC5106 Part Number JAC5001A NOTE For detailed component descriptions and sizes, please see the K-Line Industries website at http://klineind.com. Contents • Twenty ORFS tee fittings in five sizes • Eight ORFS 90° elbow fittings in four sizes •...
HYDRAULICS Component Location See Figures 4-8 and 4-9. TN5276, TN5243 Brake Valve Center Cutting Unit Motor Gear Pump Right Front Lift Cylinder Left Front Lift Cylinder Right Front Cutting Unit Motor Left Front Cutting Unit Motor Right Rear Lift Cylinder Center Lift Cylinder Left Wing Lift Cylinder Left Wing Cutting Unit Motor...
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HYDRAULICS TN5382 Radiator/Hydraulic Oil Cooler Hydraulic Oil Filter Deck Valve Right Rear Cutting Unit Motor Figure 4-9: Component Location 4181383-Second Edition...
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Deck Valve .89ci Left Rear Deck .89ci Right Front .89ci 2800 psi Deck Center Deck Left Front Deck 630 psi .89ci .89ci Right Rear Deck 6-12 4181383-Second Edition...
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Traction 3625 psi Pump Gear Pump 3000 0.85 ci 2.81 ci .89 ci .89 ci .89 ci .5 ci 4350 psi Valve (AR722T Only) 295 psi .046 .031 B N A B N A Wing Deck Valve (AR722T Only) Left Wing 3000 Deck Cooler...
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24.0 ci 24.0 ci Right Front Wheel Motor Left Front Wheel Motor 400 psi 400 psi Valve .052 18.7 ci 18.7 ci Right Rear Left Rear Wheel Motor Wheel Motor 350 psi Brake Release Valve 6-14 4181383-Second Edition...
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Left Wing Cylinder (AR722 Only) Wing Lift Valve (AR722T Only) .040 Steering Valve One Way Orifice One Way Orifice .040 100~800 psi Right Wing 3.84 Cylinder (AR722 Only) Steering Cylinder Lift Valve .029 .029 .026 .026 .029 .029 .029 One Way One Way Orifice Orifice...
Theory of Operation and Diagnostic Information Steering Circuit Schematic and Theory of Operation System Conditions: • Engine running • Steering wheel turned to the right or left (right turn shown) NOTE Right turn shown. Hydraulic oil is drawn from the hydraulic oil tank by the steering section of the gear pump assembly.
Lift Circuit Schematic and Theory of Oil from the rod end of the lift cylinders flows back to the wing lift valve assembly through port “B”. Oil exits the Operation wing lift valve assembly through port “T,” and flows to the return filter and oil cooler, and then back to the hydraulic System Conditions: oil tank.
Lift Circuit (AR522) Schematic Figure 6-15 To Traction Pump Gear .89 ci .89 ci .89 ci .5 ci Pump (AR722T Only) To Deck Valve (P1) To Wing Deck Valve (P) (AR722T Only) To Deck Valve (P2) 3.84 Steering Cylinder Steering Valve Lift Valve To Brake Release Valve (ST)
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Lift Circuit (AR722T) Schematic Figures 6-16 Wing Lift Valve (AR722T Only) .040 To Traction Pump One Way Left Wing Orifice Cylinder (AR722T Only) One Way Orifice Gear .89 ci .89 ci .89 ci .5 ci Pump .040 100~800 psi (AR722T Only) To Deck Valve (P1) To Wing Deck Right Wing...
Lower Circuit Schematic and Theory With the wing lowering solenoid valve energized, oil flows through, exits the wing lift valve assembly through port of Operation “T”, and flows to the return filter and oil cooler, and then back to the hydraulic oil tank. System Conditions: Gravity pulls the cutting units down, pushing against the •...
Lower Circuit (AR522) Schematic Figure 6-19 To Traction Pump Gear .89 ci .89 ci .89 ci .5 ci Pump (AR722T Only) To Deck Valve (P1) To Wing Deck Valve (P) (AR722T Only) To Deck Valve (P2) 3.84 Steering Cylinder Steering Valve Lift Valve To Brake Release Valve (ST)
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Lower Circuit (AR722T) Schematic Figure 6-20 Wing Lift Valve (AR722T Only) .040 To Traction Pump One Way Left Wing Orifice Cylinder (AR722T Only) One Way Orifice Gear .89 ci .89 ci .89 ci .5 ci Pump .040 100~800 psi (AR722T Only) To Deck Valve (P1) To Wing Deck Right Wing...
Float and Traction Control Circuit Schematic and Theory of Operation System Conditions: • Engine running • Traction control switch in the on position NOTES See “Float and Traction control - Theory of Operation” for the electrical operation of this circuit. AR522 The purpose of the traction control circuit is to allow the transfer of weight from the cutting units to the wheels to...
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To Traction Pump Gear .89 ci .89 ci .89 ci .5 ci Pump (AR722T Only) To Deck Valve (P1) To Wing Deck Steering Valve Valve (P) (AR722T Only) To Deck Valve (P2) 3.84 Steering Cylinder To Brake Release Valve (ST) .029 .029 .026...
Mow Circuit Schematic and Theory of Mow Circuit (On) Theory of Operation Operation System Conditions: • Engine running Wing Lift Valve (AR722T Only) .040 To Traction Pump One Way Left Wing Orifice Cylinder (AR722T Only) One Way Orifice Gear .89 ci .89 ci .89 ci .5 ci...
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• Cutting units lowered System Relief • PTO switch in the on position If there is resistance to flow at the cutting unit motors, causing oil pressure to rise above the relief valve setting • Park brake released of 2800 psi (193 bar), the relief valve will open. When the relief valve opens, oil flows through the check valve, NOTE resulting in a pressure drop allowing check valve 1 to...
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Return oil from the cutting unit motors enters the deck AR722 valve through port “B1” (right wing cutting unit motor) or System Conditions: “B2” (left wing or both cutting unit motors) and flows • Engine running through the relief valve. It then flows back to the return •...
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Mow On Circuit Schematic See Figure 6-29 4181383-Second Edition 6-31...
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Mow On Circuit Schematic (Continued) Inlet or Drain Oil Operating Pressure Oil Return Oil Deck Valve .89ci Left Rear Deck .89ci 2800 psi Right Front .89ci Deck Center Front Deck Left Front Deck 630 psi .89ci .89ci Right Rear Deck 6-32 4181383-Second Edition...
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Mow Off Circuit Schematic See Figure 6-30 To Traction Pump Inlet or Drain Oil Gear Operating Pressure Oil .89 ci .89 ci .89 ci .5 ci Pump Return Oil (AR722T Only) To Steering Valve (P) Left Wing 3000 Deck Cooler (AR722T Only) 25Psi Crack...
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Mow Off Circuit Schematic (Continued) Inlet or Drain Oil Operating Pressure Oil Return Oil Deck Valve .89ci Left Rear Deck .89ci 2800 psi Right Front .89ci Deck Center Front Deck Left Front Deck 630 psi .89ci .89ci Right Rear Deck 6-34 4181383-Second Edition...
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Mow ON (right wing off) Circuit Schematic See Figure 6-31 To Traction Pump Inlet or Drain Oil Gear Operating Pressure Oil .89 ci .89 ci .89 ci .5 ci Pump Return Oil (AR722T Only) To Steering Valve (P) Left Wing 3000 Deck Cooler...
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Mow ON (right wing off) Circuit Schematic (Continued) Inlet or Drain Oil Operating Pressure Oil Return Oil Deck Valve .89ci Left Rear Deck .89ci 2800 psi Right Front .89ci Deck Center Front Deck Left Front Deck 630 psi .89ci .89ci Right Rear Deck 6-36...
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To Traction Pump Inlet or Drain Oil Gear Operating Pressure Oil .89 ci .89 ci .89 ci .5 ci Pump Return Oil (AR722T Only) To Steering Valve (P) Left Wing 3000 Deck Cooler (AR722T Only) 25Psi Crack .89ci Bypass Micron Wing Deck Valve (AR722T Only)
Field Test Procedures When a hydraulic system failure occurs, some simple effective tests can be performed prior to using a test instrument. The results of these tests can lead you to the suspected component failure. More extensive test procedures, using test instruments, are presented later in this section.
2. With the engine running, turn the steering wheel all the way to the right, and then all the way to the left. Does the steering wheel continue to turn after full left or right movement of the steering cylinder? Proceed to step 3.
Instrument Test Procedure 6. Install a separate hose on the case drain fitting and place the free end in the container. Secure the hose to prevent spills. Instrument Test Overview WARNING The following tests are specifically designed to approach hydraulic testing on a system level.
Front Cutting Units Circuit Calculations: See Figures 6-3 through 6-5. Circuit Test No Load Flow = 10 gpm IMPORTANT Loaded Flow = 6.5 gpm • This test works together with the front cutting 10 – 6.5 / 10 x 100 = Total Circuit Leakage 35% units motors test to isolate a problem with the front cutting unit circuit.
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WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 7. Install a suitable blocking device or tool in right front cutting unit, preventing cutting unit from turning. Open flow meter valve (4) completely.
Front Cutting Units Pump Test 8. Bypass the seat switch. See Figures 6-6 through 6-8. NOTE Verify engine rpm is within specification (2850 ± 50 rpm) WARNING to ensure accurate hydraulic test results. The hydraulic system is under pressure, and the 9.
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TN1363 Figure 6-7 3. Install blocking disk between hose (1) and tee fitting (3). TN5461 Figure 6-8: Front Cutting Units Pump Test—Install Blocking Disk between Hose (1) and Tee Fitting (3) 4. Open flow meter valve (2) completely. 5. Bypass the seat switch. NOTE Verify engine rpm is within specification (2850 ±...
Front Cutting Units Circuit Valve 7. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 1300 psi (90 bar) Tests or one-half of the relief valve rating is reached. Warm oil to 120–150° F (49–65° C); open valve fully after See Figures 6-9 through 6-11.
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TN1363 Figure 6-11 4. Open flow meter valve (2) completely. 5. Bypass the seat switch. NOTE Verify engine rpm is within specification (2850 ± 50 rpm) to ensure accurate hydraulic test results. 6. Start engine and run at full throttle (2850 ± 50 rpm). 7.
1. Park the mower safely. (See “Park Mower Safely” on CAUTION page 1-5.) 2. Perform front cutting units circuit valve test. (See Do not exceed 2650 psi (183 bar) when testing “Front Cutting Units Circuit Valve Tests” on system relief valve, or equipment damage may page 6-38.) occur.
Front Cutting Units Motors Test WARNING See Figures 6-13 and 6-14. Safely block cutting unit from rotating using a IMPORTANT suitable device or tool. Failure to follow appropriate safety precaution may result in death • This test works together with the front cutting or serious injury.
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12. Calculate right front cutting unit motor leakage. (Step 10 of front cutting units circuit valve tests – Step 10 / Step 10 of front cutting units circuit valve tests x 100 = Leak Percentage) Is right front cutting unit motor leakage 10% or less? The right front cutting unit motor is good.
Rear Cutting Units Circuit Test 23. Calculate left front cutting unit motor leakage. (Step 10 – Step 21 / Step 10 x 100 = Leak See Figures 6-15 through 6-17. Percentage) IMPORTANT Is left front cutting unit motor leakage 10% or less? •...
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WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 7. Install a suitable blocking device or tool in left rear cutting unit, preventing cutting unit from turning. Open flow meter valve (4) completely.
Rear Cutting Units Pump Test 8. Bypass the seat switch. See Figures 6-18 through 6-20. NOTE Verify engine rpm is within specification (2850 ± 50 rpm) WARNING to ensure accurate hydraulic test results. The hydraulic system is under pressure, and the 9.
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TN1363 Figure 6-19 3. Install blocking disk between hose (1) and tee fitting (3). TN5467 Figure 6-20: Rear Cutting Units Pump Test—Install Blocking Disk Between Hose (1) and Tee Fitting (3) 4. Open flow meter valve (2) completely. 5. Bypass the seat switch. NOTE Verify engine rpm is within specification (2850 ±...
Rear Cutting Units Circuit Valve Tests 7. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 1300 psi (90 bar) See Figures 6-21 through 6-23. or one-half of the relief valve rating is reached. Warm ...
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TN1363 Figure 6-23 4. Open flow meter valve (2) completely. 5. Bypass the seat switch. NOTE Verify engine rpm is within specification (2850 ± 50 rpm) to ensure accurate hydraulic test results. 6. Start engine and run at full throttle (2850 ± 50 rpm). 7.
Rear Cutting Units Motors Test CAUTION See Figures 6-24 through 6-27 Do not exceed 2650 psi (183 bar) when testing IMPORTANT system relief valve, or equipment damage may occur. • This test works together with the rear cutting units circuit test to isolate a problem with the rear cutting units circuit.
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WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 4. Install a suitable blocking device or tool in left rear cutting unit, preventing cutting unit from turning. TN1363 Figure 6-25 5.
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13. Remove device or tool from left rear cutting unit. 15. Open flow meter valve (3) completely. 16. Connect park brake switch. WARNING NOTE Safely block cutting unit from rotating using a Verify engine rpm is within specification (2850 ± 50 rpm) suitable device or tool.
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29. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (3) until a reading of 1300 psi (90 bar) or one-half of the relief valve rating is reached. Warm oil to 120–150° F (49–65° C); open valve fully after operating temperature is reached.
Lift/Steer System Relief Valve Pressure Test See Figures 6-28 through 6-30. WARNING The hydraulic system is under pressure, and the oil will be hot. • Always relieve pressure in the hydraulic system before performing service. • Failure to follow appropriate safety precautions may result in death or serious injury.
10. Stop engine. Is lift/steer system relief pressure 1595 psi (110 bar)? Lift/steer system relief valve is good. Proceed to step 11. Test lift/steer pump. (See “Lift/Steer Pump Test” on page 6-56.) Test lift cylinder. (See “Lift Cylinder Leakage Test” on page 6-31.) Replace steering valve.
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TN5271 Figure 6-31 3. Disconnect hose (2) from fitting (1). TN1363 Figure 6-32 4. Install tee fitting (5) to fitting (1). 5. Connect flow meter inlet test hose (6) and hose (2) to tee fitting (5). TN5470 Figure 6-33: Lift System Test—Install Tee Fitting (5) to Fitting (1) and Connect Flow Meter Inlet Test Hose (6) and Hose (2) to Tee Fitting (5) NOTE...
Lift/Steer Pump Test CAUTION See Figures 6-34 and 6-35. Do not exceed 1800 psi (124 bar) as this test does WARNING not utilize system relief. The hydraulic system is under pressure, and the 10. Use the flow meter to warm the hydraulic oil. Turn the oil will be hot.
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CAUTION Do not exceed 1800 psi (124 bar) as this test does not utilize system relief. 6. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (4) until a reading of 900 psi (62 bar) or one-half of the relief valve rating is reached.
Lift Valve Test See Figures 6-36 through 6-38. WARNING The hydraulic system is under pressure, and the oil will be hot. • Always relieve pressure in the hydraulic system before performing service. • Failure to follow appropriate safety precautions may result in death or serious injury.
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11. Calculate lift valve leakage. (Step 8 of previous test – Step 9 / Step 8 of previous test x 100 = Leak Percentage) Is lift valve leakage 10% or less? The lift valve is good. Proceed to step 12. Proceed to next question.
Disassembly, Inspection, and Assembly See Figures 6-42 and 6-43 TN5157 Retaining Ring Thrust Plate (6) Splined Connecting Shaft (2) Bolt (4) Seal Gear Set (Drive Shaft) Dowel Pin (4) Washer (4) Front Cover/Flange Body (3) Spacer (2) Gear Set, End Backup Washer (6) Seal (6) Gear Set, Intermediate...
Disassembly Notes Assembly Notes • Do not disassemble pump for repair unless test NOTICE procedures indicate internal leakage. • Never pry components apart. Use a soft face It is important that all component parts are hammer, and gently tap housing and shaft to absolutely clean, as contamination can result in separate pump bodies.
Lift Valve NOTES • Label hydraulic hoses to aid in installation. Removal and Installation • Close all openings with caps or plugs to prevent See Figures 6-44 through 6-46. contamination. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2.
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Disassembly, Inspection, and Assembly See Figure 6-47. TN5200 Check Valve Cartridge Raise Solenoid Coil Lift Valve Fitting (2) Lower Solenoid Coil Raise Solenoid Valve Fitting (10) Lower/Proportional Fitting (2) 90° Fitting Solenoid Valve Figure 6-47 NOTE NOTICE Note the position and orientation of the fittings before It is important that all component parts are removing to ensure correct installation.
Assembly Notes NOTE NOTICE Label connector before disconnecting to ensure correct installation. It is important that all component parts are 4. Disconnect electrical connector (3) from solenoid. absolutely clean, as contamination can result in serious damage and/or improper operation. NOTES Never use shop towels or rags to dry parts after •...
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Disassembly, Inspection, and Assembly See Figure 6-49. 10 11 TN5201, TN5202 Fitting Solenoid Valve Coil 90° Fitting Relief Valve, 630 psi Fitting (2) Solenoid Valve Fitting Pilot Piston Deck Valve Fitting (2) Check Valve (2) Relief Valve, 2800 psi Figure 6-49 NOTE Note the position and orientation of the fittings before removing to ensure correct installation.
Assembly Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air.
TN5387 Figure 6-52 NOTES • Label all hydraulic hoses before disconnecting to TN5203 ensure correct installation. Figure 6-51 • All of the lift cylinders have an orifice installed between the hose and one of the cylinder fittings. NOTE Note the location of the orifice and recover the orifice Note the position and orientation of the fittings before when removing the hydraulic hoses.
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Disassembly, Inspection, and Assembly 1. Drain oil from lift cylinder. See Figures 6-53 through 6-55. NOTES • Note the position and orientation of the fittings before removing to ensure correct installation. • The front center lift cylinder has the ports located differently from the other lift cylinders, but is serviced in the same manner.
TN5095 Grease Fitting Piston Rod Seal Barrel Rod Wiper O-Ring Wear Ring O-Ring Rod Guide Piston Seal Backup Ring Wear Ring (2) Figure 6-55 Assembly Notes NOTE NOTICE During repair of the cylinder, use extreme care not to damage the barrel, piston, rod, and sealing surfaces of It is important that all component parts are the cylinder.
Hydraulic Oil Tank Removal and Installation See Figures 6-56 through 6-58. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Disconnect the negative (–) battery cable from the battery. 3. Place a suitable container beneath the hydraulic oil tank.
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Installation Notes Required Materials Anti-Seize Compound • Install hydraulic oil tank by reversing the order of removal. CAUTION • When connecting fittings to the tank, be sure to hold the tank fitting with the proper wrench. If the proper wrench is not used, the fitting in the tank might break loose from the plastic and cause it to leak.
STEERING Specifications Test Specifications Steering System Leakage Zero—Nominal Amount pt (L) Test—Cylinder Leakage Repair Specifications Steering Wheel Nut 25–30 (34–41) lb-ft (N·m) Rear Axle End Play 0.010–0060 inch (0.25–1.5 mm) in. (mm) Steering Cylinder Ball Joint-to- 80–110 (108–149) lb-ft (N·m) Steering Arm Torque Tie Rod Ball Joint-to-Steering Arm 60 ±...
STEERING Tests and Adjustments Steering Relief Valve Pressure Test See Figures 5-3 and 5-4. Tie Rod Adjustment WARNING See Figure 5-2. • The hydraulic system is under pressure, and the oil will be hot. • Always relieve pressure in the hydraulic system before performing service.
STEERING Steering Leakage Test See Figure 5-5. 1. Operate hydraulic system until oil temperature is at 120–150° F (49–65° C). 2. Turn steering wheel fully left against stop. 3. Park the mower safely. (See “Park Mower Safely” on page 1-5.) WARNING The hydraulic system is under pressure, and the Figure 5-4...
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STEERING WARNING Do not turn steering wheel to the right. Failure to follow appropriate safety precautions may result in death or serious injury. 6. With engine off, turn steering wheel fully left against stop. 7. Check for oil leakage in the drain pan. Is steering cylinder leakage a nominal amount of oil or less? Proceed to step 10.
STEERING Repair Steering Valve Removal and Installation Steering Wheel See Figures 5-7 through 5-12. Removal and Installation 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) See Figure 5-6. 2. Remove the steering wheel. (See “Steering Wheel” 1.
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STEERING TN5405 Figure 5-10 Figure 5-8 12. Remove four screws (6) and lock washers (7). TN5406 TN5403 Figure 5-11 Figure 5-9 13. Remove steering column (8) from steering unit (9). NOTES 14. Support the steering unit (9). • Label all hydraulic hoses and record their locations to ensure correct installation.
STEERING NOTICE Do not clamp the steering valve assembly directly into a vise. Clamping the steering valve directly into a vise may damage or distort the steering valve. TN5404 Figure 5-12 15. Remove four screws (11), lock washers (12), and spacers (13), and remove steering unit (9).
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STEERING Disassembly See Figure 5-15. TN1428 Nut (4) Valve Plate (Matched Set) Commutator Seal Face Seal Port Cover Spring Commutator Cover Seal Spacer Relief Valve Assembly Seal Ring Commutator Ring Upper Cover Plate Seal Ring Hex Drive Assembly Commutator Retaining Ring Ball, 9/32 inch Isolation Manifold Alignment Pin (5)
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STEERING Inspection CAUTION See Figure 5-16. Wear eye protection when assembling and IMPORTANT disassembling the steering valve. Springs and Always replace springs as a set. other objects may be propelled into the air, causing eye injury. 1. Inspect springs (9 and 13) for bent, broken, or distorted coils.
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STEERING Assembly See Figures 5-17 through 5-20. 26 27 36 37 TN1428 Valve Plate (Matched Set) Commutator Seal Face Seal Port Cover Spring (3) Commutator Cover Seal Spacer Relief Valve Assembly Seal Ring Commutator Ring Upper Cover Plate Seal Ring Hex Drive Assembly Commutator Retaining Ring...
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STEERING 9. Apply a small amount of grease to the drive link Service Part Kits spacer (49) and install in the rotor (50). 10. Place the commutator (47) on top of the rotor (50) Seal Kit (Jacobsen PN 4197940) with the aligning pin holes facing up. Place a few Metering Assembly Kit (Jacobsen PN 5003220) drops of oil in each recess of the commutator (47).
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STEERING NOTE The metering package should rotate inside the stator. If binding occurs, disassemble the metering package, correct the cause, and repeat the assembly process. 18. Place the metering ring (20) on top of the upper cover plate (36) with the alignment pin holes up. 19.
STEERING 1. Park the mower safely. (See “Park Mower Safely” on NOTES page 1-5.) • Label all hydraulic hoses and record their locations to 2. Remove steering valve. (See “Steering Valve” on page 5-7.) ensure correct installation. • Plug hydraulic hoses after disconnecting to prevent 3.
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STEERING TN13? TN1491 Figure 5-24 NOTES • Record the location and orientation of fittings (14 and 16) before removing to ensure correct installation. • Record the orientation of the ball joints before removing to ensure correct installation. • Record the number of turns required to remove each ball joint.
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STEERING Disassembly, Inspection, and Assembly See Figure 5-25. TN1471 Barrel Pistion Seal Ring O-Ring Rod Guide Right Ball Joint Left Ball Joint Piston Ring O-Ring Rod Wiper Figure 5-25 1. Use a spanner wrench to remove rod guide (10) from WARNING barrel (1).
STEERING Tie Rod Assembly NOTICE Removal and Installation It is important that all components are absolutely See Figure 5-26. clean, as contamination can result in serious damage and/or improper operation. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) Never use shop towels or rags to dry parts after cleaning, as lint may clog passages.
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STEERING Disassembly, Inspection, and Assembly See Figure 5-27. TN1387 Threaded Ball Joint Right Tie Rod Grease Fitting Hex Head Bolt Lock Washer Lock Washer Tie Rod Clamp Grease Fitting Hex Head Bolt Tie Rod Clamp Threaded Ball Joint Left Ball Joint Measurement Figure 5-27 Disassembly Notes Assembly Notes...
STEERING Rear Axle Removal and Installation See Figures 5-28 and 5-29. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove rear wheel motors. (See “Rear Wheel Motor” on page 5-60.) TN5154 Figure 5-29 4. Support the rear axle assembly (11) using an appropriate lifting device.
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STEERING Disassembly, Inspection, and Assembly See Figure 5-30. TN1388 Bushing (4) Thrust Washer (6) Left Steering Arm Castle Nut (2) Axle Grease Fitting (2) Motor Mount (2) Steering Cylinder Cotter Pin (2) Thrust Bearing (2) Cotter Pin (2) Ball Joint (2) Castle Nut (2) Hex Bolt (6) Thrust Washer (2)
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STEERING Assembly Notes • Replace any bushings, bearings, and ball joints that were damaged or had excessive wear. • Replace or repair steering cylinder if dented or leaking. • Tighten tie rod castle nuts (16) to 60 ± 5 lb-ft (81 ±...
CUTTING UNITS Component Location See Figure 6-1. TN5243, TN5244, TN1501 Right Rear Cutting Unit Right Front Cutting Unit Deck Frame Left Front Cutting Unit Deck Roller Drive Motor Center Cutting Unit Deck Caster Wheel Deck Yoke Figure 6-1: Component Location 4181383-Third Edition...
CUTTING UNITS Troubleshooting Mechanical Troubleshooting Condition Probable Cause Remedy Drive motors do not reach full speed. Engine speed is insufficient, not set to Check/adjust engine speed. (Refer to specification. “Safety, Operation, and Maintenance Manual.”) Rotary drive motors and/or hydraulic Check hydraulic system performance system performance is reduced.
CUTTING UNITS Quality of Cut Troubleshooting Factors That Affect Cut Appearance In most cases, information provided by the user/customer will provide the basis for the repairs and adjustments that are required. However, it is recommended that a “test cut” be performed to evaluate the mower’s performance before beginning repairs.
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CUTTING UNITS Definition of Terms The following terms are used to describe various cut appearance symptoms. Washboarding Washboarding is a cyclical pattern of varying cutting heights, resulting in a wave-like cut appearance. In most cases, the wave tip-to-tip distance is approximately 6—8 in.
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CUTTING UNITS Step Cutting Step cutting occurs when grass is cut taller on one side of a cutting unit than on the other, or on one side of the mower than on the other. This is usually caused by mechanical wear or an incorrect roller or deck caster adjustment.
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CUTTING UNITS Scalping Scalping is a condition in which areas of grass are cut noticeably shorter than the surrounding areas, resulting in a light green or even brown patch. This is usually caused by an excessively low height-of-cut setting and/or uneven turf.
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CUTTING UNITS Stragglers Stragglers are scattered blades of uncut or poorly cut grass. TN0223 NOTE: Arrow indicates direction of travel. Probable Cause Remedy Dull cutting blade(s). Sharpen blade(s). (Refer to “Safety, Operation, and Maintenance Manual.”) Mowing (ground) speed is too fast. Reduce mowing (ground) speed.
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CUTTING UNITS Streaks A streak is a line of uncut grass. This is usually caused by a damaged blade. TN0224 NOTE: Arrow indicates direction of travel. Probable Cause Remedy Replace blade(s). (See “Blade” on page 6-15.) Damaged blade(s). Turning too aggressively. Cutting units don’t overlap during turns Turn less aggressively to allow cutting units to overlap.
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CUTTING UNITS Windrowing Windrowing is the deposit of clippings concentrated at one end of cutting unit(s) or between cutting units, forming line(s) in the direction of travel. TN0225 NOTE: Arrow indicates direction of travel. Probable Cause Remedy Grass is too tall. Mow more often.
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CUTTING UNITS Mismatched Cutting Units Mismatched cutting units cause a pattern of varying cutting heights, resulting in a stepped cut appearance, usually due to a different HOC (height-of-cut) adjustment from one cutting unit to another. TN1278 NOTE: Arrow indicates direction of travel. Probable Cause Remedy HOC inconsistent from one cutting unit to another.
CUTTING UNITS Repair Installation Notes • Install deck motor by reversing the order of removal. • Install motor on the deck, making sure it is in proper Deck Motor orientation with the marks made on removal. Removal and Installation • Inspect O-rings on fittings before installation. See Figure 6-2.
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CUTTING UNITS Disassembly and Assembly See Figure 6-3. TN1518 Shaft Seal Sleeve Bearing Holder Screw (4) Gasket Retaining Ring Check Valve Backing Seal Shaft Seal Support Shaft Spring Seal Retaining Ring Sleeve Bearing Plug Thrust Plate Shaft Seal Front Cover Pump Body Driven Gear Seal (2)
CUTTING UNITS Rotary Deck NOTICE Removal and Installation It is important that all motor parts are absolutely See Figures 6-4 and 6-5. clean, as contamination can result in serious damage and/or improper operation. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) Never use shop towels or rags to dry parts after cleaning, as lint may clog passages.
CUTTING UNITS Blade Removal and Installation See Figure 6-6. 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Raise and support the cutting units. (Refer to “Safety, Operation, and Maintenance Manual.”) 3. Disconnect the negative (–) battery cable at the battery.
CUTTING UNITS Front Deck Yoke Installation Notes • Install front deck yoke by reversing the order of Removal and Installation removal. See Figure 6-7. • Apply grease on lift arm pivot shaft bushings (4) and lift arm pivot shaft (2) before installation. (Refer to 1.
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CUTTING UNITS 4. Roll the cutting unit forward until the deck yoke (5) clears the lift arm pivot shaft (2). Retain lift arm shaft bushings (4) inside deck yoke (5). 5. Remove lock nut (7), washers (6 and 9), and screw (10) from both sides of the deck frame (8) and deck yoke (5).
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CUTTING UNITS Disassembly and Assembly See Figure 6-12. TN5140 Snap Ring Spacer (2) Yoke Spacer Spacer Caster Wheel Yoke O-Ring (2) Caster Wheel Flat Washer (4) Screw Grease Seal (4) Grease Fitting Bearing Cup and Cone (2) Lock Washer Figure 6-12 6-18 4181383-Third Edition...
CUTTING UNITS Deck Roller Removal and Installation See Figures 6-13 and 6-14. TN1418 Figure 6-13 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove mower deck. (See “Rotary Deck” on page 6-14.) 3. Remove deck yoke. (See “Front Deck Yoke” on page 6-16.) (See “Rear Deck Yoke”...
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CUTTING UNITS TN1420 Figure 6-14 NOTE Steps 5 through 8 apply to both sides of the roller assembly. 5. Loosen screw (19) from collar (13) on roller shaft (14). 6. Remove pin (15) from roller shaft (14). 7. Remove lock nut (17) and washer (18) from scraper shaft (16).
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CUTTING UNITS Disassembly, Inspection, and Assembly See Figure 6-15. TN5141 Figure 6-15 1. Park the mower safely. (See “Park Mower Safely” on page 1-5.) 2. Remove deck roller from cutting unit. (See “Deck Roller” on page 6-19.) NOTE Do not remove bearing cone (4) unless it is necessary to replace the bearing (3).
CUTTING UNITS Mower Deck Housing Disassembly and Assembly See Figure 6-16. TN1409 Figure 6-16 1. Remove nuts (1) and washers (2) from screws (5) (two for mulch cover, three for rear discharge deflector). 2. Remove mulch cover (3) or rear discharge deflector (4) from mower deck (6).
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A worldwide dealer network and factory trained technicians backed by Jacobsen Parts Xpress provide reliable, high-quality product support. ACCESS ADDITIONAL MANUALS ONLINE (AR-522 T4F) (AR-722 T4F) When Performance Matters. ™ Jacobsen, A Textron Company 11108 Quality Drive, Charlotte, NC 28273 www.Jacobsen.com 800-848-1636...
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