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SERIES 50 ACCESSORY DRIVE

The accessory drive assembly is mounted to the front of the gear case cover and utilizes a two-groove pulley to drive the alternator. See Figure 20288 . ‪

1. Locknut ‪

8. Drive Gear ‪

2. Mounting Bolts (5) ‪

9. O-ring ‪

3. Drive Housing ‪

10. Gear Case Cover ‪

4. Snap Ring (Small) ‪

11. Needle Bearing ‪

5. Ball Bearing ‪

12. Oil Seal ‪

6. Snap Ring (Large) ‪

13. Pulley ‪

7. Driveshaft ‪

Accessory Drive Assembly Related Parts

The accessory drive assembly is splash fed oil through two holes in the casting of the accessory drive housing. The oil returns to the crankcase via the gear case. ‪

The accessory drive is driven by a drive gear which is pressed onto the driveshaft. The drive gear meshes with the bull gear and is driven at 2.41 times engine speed. ‪

The driveshaft is supported by a ball bearing at the drive end and a needle bearing at the pulley end. ‪

Note: A design change has been made to the accessory drive assembly. The needle bearing inner race is now incorporated into the driveshaft. See Figure 20288 .

An O-ring is used to seal the accessory drive housing to the gear case cover. ‪

Repair and Replacement of the Accessory Drive

To determine if repair is possible or replacement is necessary, perform the following procedures. See Figure 24091 . ‪

Flowchart for Repair or Replacement of Accessory Drive

Cleaning and Removal of the Accessory Drive

Precleaning is not necessary. ‪

Remove the accessory drive as follows: ‪

  1. Loosen the alternator mounting bolts and the adjusting rod nuts to get slack in the alternator drive belts. Remove the alternator drive belts. See Figure 20139 .

    Alternator Mounting Bolts

  2. Loosen and remove the five bolts that secure the accessory drive assembly to the gear case cover.
  3. Remove the accessory drive assembly by pulling it straight out of the gear case cover to avoid damaging the rubber O-ring. See Figure 24289 .

    Accessory Drive Assembly Removal

Disassembly of the Accessory Drive

Disassemble the accessory drive as follows: ‪

Note: For disassembly and assembly of the accessory drive use toolset J 36024-D. See Figure 42610j

Note: Engines built after December 2000, use the following tools for accessory drive seal removal and installation: J 45533 seal remover, J 45833 seal installer, and J 45877 seal runout gauge adapter to verify proper installation of seal in accessory drive. These tools are part of toolset J 36024-D. See Figure 42610j .

Note: The seal, pulley and pulley nut are the only serviceable parts of the accessory drive assembly with the unitized oil seal.

Accessory Drive Service Tool Set J 36024-D

  1. Attach the accessory drive gear to the holding fixture, J 36024-3 part of J 36024C , using the three bolts provided. See Figure 20290 .

    Holding Fixture

  2. Place the accessory drive assembly holding fixture into a vise. See Figure 20291 .

    Accessory Drive Pulley Locknut Removal

  3. Loosen and remove the accessory drive pulley locknut.
  4. Remove the accessory drive pulley by tapping it with a rubber hammer or fiber mallet. If the pulley does not come off easily, use a puller to remove it. See Figure 20291 .

    1. Seal Sleeve ‪

    J 45533 Accessory Drive Seal Remover

    Note: Perform steps 5, 6, and 7 unitzed seal removal procedure, for accessory drive assemblies on engines built after December 2000.

  5. Using J 45533 (part of toolset J 36024-D ), remove seal sleeve.
    1. Ensure taper end of puller bolt is pointed toward inside jaws. See Figure 42559 .
    2. Place inside jaws of tool over sleeve. See Figure 42559 .
    3. Finger tighten hex bolt on side of tool.
    4. Remove sleeve by tightening puller bolt.
  6. Removal of seal.
    1. Invert puller bolt. See Figure 42560

      J 45533 Invert Puller Bolt

    2. Loosen hex bolt on side of tool.
    3. Using a rubber mallet, gently drive outside jaws between seal and shaft through the rubber membrane of seal until tool bottoms out.
    4. Finger tighten hex bolt on side of tool.
    5. Remove seal by tightening puller bolt.
  7. Clean accessory drive housing at seal location.
  8. Position the accessory drive assembly on a press bed with the holding fixture supported. See Figure 20292 .

    Accessory Drive Gear Removal

  9. Using a press, apply pressure through the access hole in the holding fixture, J 36024-3 part of J 36024C , and press the driveshaft out of the gear.
  10. Remove the snap ring from the accessory drive housing. See Figure 20293 .

    Snap Ring Removal

  11. Turn the housing over and support the accessory drive housing on the machined surface using Vee-blocks.
  12. Using a press, apply pressure to the pulley end of the shaft and remove the shaft and bearing assembly.
  13. Turn the accessory drive housing over, and support it on the attaching bolt bosses using Vee-blocks.

    NOTICE:

    For assemblies with inner race for needle bearing, place the accessory driveshaft in a vise with soft jaws taking care not to damage the shaft surface. ‪

  14. Install needle bearing remover and installer, J 36024-2 part of J 36024C . See Figure 20294 . Apply pressure to J 36024-2 part of J 36024C , and remove the needle bearing.

    Needle Bearing Removal

  15. Apply pressure to J 36024-2 part of J 36024C and remove the needle bearing.
  16. Remove the snap ring from the accessory driveshaft. See Figure 24414 .

    Snap Ring Removal

  17. Position two steel press plates under the ball bearing outer race. See Figure 24415 .

    Ball Bearing Removal

    Note: Whenever the needle or ball bearing is removed from the shaft, they MUST be replaced with new bearing assemblies.

  18. Use a press to apply pressure to the top of the shaft and remove the ball bearing from the shaft.
Inspection of the Accessory Drive

Clean the accessory drive prior to inspection as follows: ‪

  1. Clean all of the parts with clean fuel oil.

    EYE INJURY

    To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.

  2. Dry parts with compressed air.

Inspect the accessory drive as follows: ‪

  1. Inspect the driveshaft for damage.
    1. Check the driveshaft for galling, pitting, cracks, or other damage.
    2. If any damage is detected, replace with a new part.

Assembly of the Accessory Drive

Assemble the accessory drive as follows: ‪

  1. Place a new ball bearing on the accessory driveshaft. Use tool J 36024-1A part of J 36024C and a press to install the bearing onto the shaft until it bottoms out against the shoulder of the driveshaft. See Figure 20298 .

    Bearing Installation

  2. Install the snap ring to the accessory driveshaft making sure it is fully seated in the groove a full 360. See Figure 24414 .

    Snap Ring Installation

  3. Place the needle bearing inner race on the accessory driveshaft. Use tool J 36024-1 part of J 36024C and a press to install the bearing inner race to the shaft until it is tight against the shoulder. See Figure 20299 .

    Note: On current design accessory driveshaft, the needle bearing inner race is incorporated into the shaft.

    Bearing Inner Race Installation

  4. Install the needle bearing to the accessory drive housing using tool J 36024-2 part of J 36024C and a press. See Figure 20300 .

    Needle Bearing Installation

    Note: The end of the bearing with the identification numbers must be against the installer.

    Note: The word INSTALL and an arrow are etched into the tool, J 36024-2 part of J 36024C , to facilitate correct bearing installation.

  5. Lubricate the oil seal contact area of the accessory drive housing with a thin film of engine oil.
  6. Install the accessory drive oil seal to the accessory drive housing using the seal installer, J 36024-4 part of J 36024C , and a plastic hammer or fiber mallet. The oil seal must be installed flush to 0.25 mm (0.010 in.) below the face of the housing. See Figure 20301 .

    Accessory Drive Oil Seal Installation

  7. Lubricate the oil seal with a thin film of engine oil.
  8. Support the holding fixture, J 36024-3 part of J 36024C on two steel plates and position the accessory drive housing into the hole in the fixture.
  9. Install the driveshaft to the housing. See Figure 20302 .

    Accessory Driveshaft Preparation

  10. Press the driveshaft into the housing by placing tool, J 36024-1A part of J 36024C , on the bearing outer race.
  11. Press the bearing into the housing until the bearing is seated against the shoulder of the housing. See Figure 20303 .

    Accessory Driveshaft Installation

  12. Install the snap ring to the accessory drive housing making sure the snap ring is fully seated in the groove a full 360. See Figure 20293 .

    Snap Ring Installation

  13. Lubricate the contact surfaces of the bearing with clean engine lubricating oil.
  14. A film of lubriplate must be applied to the drive gear end of the accessory driveshaft. See Figure 20304 .

    Drive Gear Installation Preparation

  15. Use a press to install the drive gear on the accessory driveshaft until it is flush with the driveshaft end. Make sure the three threaded holes are facing up. See Figure 20305 .

    Note: Support the opposite end of the driveshaft on the press bed when pressing the gear on the shaft. A minimum press load of 17.8 kN (4000 lb) must be obtained when pressing the gear on the shaft.

    Accessory Drive Gear Installation

    Note: For accessory drive assemblies with unitized seals, effective with engines built after December 2000 perform the procedures in steps 16 and 17.

  16. Install seal using J 45833 (part of toolset J 36024-D) by tightening installer nut until a positive stop is obtained. See Figure 42558 .

    1. Vise ‪

    J 45833 Accessory Drive Seal Installer

  17. Measure sleeve and run out using J 45877 (part of toolset J 36024-D) and a dial indicator. Total indicator deflection should not exceed 0.0762 mm (0.003 in.) for the sleeve and 0.1778 mm (0.007 in.) for the seal. If the run out is greater for either measurement, install a new seal. See Figure 42561 .

    1. Dial Indicator ‪

    2. Seal Sleeve ‪

    J 45877 Seal Run Out Gauge Adaptor

  18. Install the accessory drive pulley to the shaft.

    Note: If necessary, use tool J 36024-1A part of J 36024C , to seat the pulley on the shaft. If pressing is necessary, the opposite (gear) end of the shaft must be supported during the pressing operation.

  19. Attach the accessory drive holding fixture, J 36024-3 part of J 36024C , to the drive gear. See Figure 20290 .
  20. Place the accessory drive assembly holding fixture into a vise.
  21. Install and torque the accessory drive pulley locknut to 360-400 Nm (266-295 lbft). See Figure 20306 .

    Accessory Drive Pulley Locknut Tightening

  22. Support the accessory drive assembly. See Figure 20307 .

    Accessory Drive Gear TIR Measurement

  23. Assemble a dial indicator and magnetic base, so that the indicator stem rests on the face of the accessory drive gear just inboard of the drive gear teeth. See Figure 20307 .
  24. Zero the dial indicator.
  25. Rotate the drive gear two full rotations. See Figure 20307 . As the gear is rotated, the dial indicator needle may register both to the left and right of zero.
  26. The total amount the dial indicator needle moves to the left and right of zero, added together, gives the total indicated run-out (TIR). Allowable TIR is 0.04 mm (0.0015 in.).

Installation of the Accessory Drive

Install the accessory drive as follows: ‪

  1. Install the O-ring seal in the groove on the drive housing.
  2. Lubricate the O-ring with petroleum jelly.
  3. Install the accessory drive housing to its original position in the gear case cover.

    Note: The word "UP" is cast into the drive housing.

  4. Install the bolts that secure the accessory drive housing to the gear case cover and torque to 30-38 Nm (22-28 lbft) using the pattern. See Figure 24416 .

    Accessory Drive Housing Bolt Torque Sequence

  5. Check the bull gear-to-accessory drive gear backlash. Refer to Section .
  6. Adjust the alternator belts. Refer to Section . Tighten the alternator mounting bolts.
  7. Install any other components removed for this procedure.