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MBE 900 AIR COMPRESSOR

The air compressor, with a power-steering pump attached, is driven by a gear on the camshaft. Perform the following procedures for removal and installation of the air compressor. ‪

Air Compressor Removal

Remove the air compressor as follows: ‪

PERSONAL INJURY

To avoid injury from scalding, drain the radiator when the engine and coolant are cool.

  1. Drain the coolant.
  2. Remove the two bolts attaching the power steering pump to the air compressor. See Figure 42475 .

    Power Steering Pump

    Note: Do not remove the power steering lines. Tie up the lines and the pump out of the way.

  3. Remove the cross plate between the compressor and the power steering pump. See Figure 42476 .

    1. Air Compressor ‪

    8. Copper Washer (2) ‪

    2. Coolant Return Line ‪

    9. Drive Nut ‪

    3. Discharge Line (air) ‪

    10. Drive Gear ‪

    4. Intake Air Line ‪

    11. O-ring ‪

    5. Unloader Air Line ‪

    12. Mounting Bolt (4 qty.) ‪

    6. Coolant Delivery Line ‪

    13. Cross Plate ‪

    7. Banjo Fitting ‪

    14. Power Steering Pump ‪

    Air Compressor Mounting and/or Removal

  4. Remove the coolant delivery line and coolant return line.

    Note: The coolant delivery line is attached to the crank angle position sensor wire with a tie strap. Cut the tie strap and remove the coolant delivery line.

    PERSONAL INJURY

    To avoid injury from the sudden release of a high-pressure hose connection, wear a face shield or goggles.

  5. Remove the three air lines. See Figure 42477 .

    1. Discharge Port ‪

    4. Unloader Port ‪

    2. Unloader Air Line ‪

    5. Discharge Air Line ‪

    3. Intake Air Line ‪

    6. Air Compressor ‪

    Air Line Attachments

    1. Remove the discharge (compressed air) line. Check the fittings for damage and replace if necessary. Check inside the discharge line for carbon deposits. If deposits are found, replace the discharge line.
    2. Remove the unloader line. Check the fittings for damage and replace if necessary.
    3. Loosen the hose clamp and remove the intake (suction) air line.
  6. Remove the four mounting bolts attaching the air compressor to the cylinder block. See Figure 42476 .
  7. Slide the drive gear away from the flywheel. Collect any oil that runs out and dispose of it properly.
Air Compressor Inspection

Inspect the air compressor as follows: ‪

  1. Inspect the O-rings on the fittings at the air system ports and replace if necessary. If the O-rings are damaged, also replace the fittings.
  2. Replace the O-ring between the power steering pump and the air compressor.
  3. Install the locking device J-46391 on the air compressor at the end of the drive shaft, where it connects to the power steering pump. This locks the drive shaft to allow removal of the drive nut. See Figure 42474j .

    Air Compressor Locking Device (J-46391)

  4. Install the two locking bolts on the locking device J-46391 and tighten them until the air compressor drive is locked and incapable of movement. See Figure 42478 .

    1. Air Compressor ‪

    2. End of Drive Shaft ‪

    Locking the Air Compressor Drive

  5. Remove the drive gear from the air compressor. See Figure 42479 .

    1. Vise ‪

    3. Drive Gear ‪

    2. Air Compressor ‪

    4. Impact Wrench ‪

    Pulling the Drive Gear

    1. Place the air compressor in a vise. Make sure it is tightly secured and cannot slip or slide out of the vise.
    2. Place an impact wrench on the drive gear nut and remove the drive nut.
    3. Remove the drive gear from the air compressor with a gear puller, if necessary.
  6. Inspect the drive gear for worn or broken teeth, spalling, and corrosion. Replace the drive gear if necessary.
  7. Install the drive gear and drive nut on the drive shaft of the air compressor. Tighten the drive nut 270 Nm (200 lbft).
  8. Remove the locking device from the air compressor and release the air compressor from the vise.

Air Compressor Installation

Install the air compressor as follows: ‪

  1. Install the air compressor.
  2. Install the four air compressor mounting bolts. Tighten each bolt 40 Nm (30 lbft).
  3. Install the three air lines. See Figure 42477 .
    1. Install the discharge line. Make sure the O-ring is properly installed on the fitting. Tighten the fitting 100 Nm (74 lbft).
    2. Install the unloader line. Make sure the O-ring is properly installed on the fitting.
    3. Install the intake air line and tighten the hose clamp.
  4. Install the two coolant lines.
    1. Pay particular attention to the coolant delivery line at the rear of the air compressor. It is difficult to line up the bolt and fitting correctly.

      Note: If necessary to line up the banjo bolt, loosen the coolant line that attaches to the rear of the engine.

    2. Note: Attach the coolant delivery line to the crank angle position sensor wire with a tie strap.

    3. Tighten the banjo bolts on the coolant delivery and return lines 40 Nm (30 lbft).
  5. Install the cross plate. Use grease to hold it in place while installing the power steering pump.
  6. Install the two bolts attaching the power steering pump to the air compressor. Tighten the bolts 40 Nm (30 lbft). See Figure 42475 .
  7. Fill the radiator with coolant.