Section 1.3 Valve and Injector Operating Mechanism

Section 1.3
Valve and Injector Operating Mechanism

The valve and injector operating mechanism is located entirely in the cylinder head. ‪

The Series 60 overhead camshaft design eliminates the need for push rods. Separate camshaft followers are not needed, since the rocker arms incorporate follower rollers riding directly on the camshaft lobes, transmitting camshaft motion to the valves and injectors. See Figure "Camshaft and Related Parts" .‪

Click to see this graphic in a separate window

Figure 1. Camshaft and Related Parts

Each of the three rocker arm assemblies contain bushings where the rocker arms are supported on the rocker arm shafts. These bushings are not serviced separately. Each intake rocker arm assembly operates two intake valves in each cylinder. Each exhaust rocker arm assembly operates two exhaust valves in each cylinder. In each set of rocker arm assemblies, the exhaust rocker assembly is the widest, straddling the intake and fuel injector rocker arm assembly. The center rocker operates the fuel injector follower. See Figure "Rocker Arm Identification" .‪

Click to see this graphic in a separate window

Figure 2. Rocker Arm Identification

The fuel injector rocker arm assembly is located between the intake and exhaust rocker arm assemblies and has a single bushing (not serviced separately). A rocker arm shaft carries three sets of rocker arm assemblies and is mounted in seats machined into the camshaft bearing caps. See Figure "Rocker Arm and Related Parts" and see Figure "Rocker Arm and Related Parts (Series 60G Engine)" .‪

Click to see this graphic in a separate window

 1. Unitized Valve Adjusting Screw Assembly; Intake‪

 5. Rocker Arm Shaft‪

 2. Locknut‪

 6. Unitized Valve Adjusting Screw Assembly; Exhaust‪

 3. Intake Rocker Arm Assembly‪

 7. Exhaust Rocker Arm Assembly‪

 4. Fuel Injector Rocker Arm Assembly‪

 8. Unitized Valve Adjusting Screw Assembly; Injector‪

Figure 3. Rocker Arm and Related Parts

Click to see this graphic in a separate window

 1. Unitized Valve Adjusting Screw Assembly; Intake‪

 5. Rocker Arm Shaft‪

 2. Locknut‪

 6. Unitized Valve Adjusting Screw Assembly; Exhaust‪

 3. Intake Rocker Arm Assembly‪

 7. Exhaust Rocker Arm Assembly‪

 4. Spacer‪

Figure 4. Rocker Arm and Related Parts (Series 60G Engine)

A new injector rocker arm assembly replaced the former injector rocker arm assembly on all model 6067-GK60 engines beginning with serial number 06R0133091, and on all model 6067-GU60 and 6067-WU60 engines beginning with serial number 06R0157655.‪

Note: When the current rocker is installed on a phosphated shaft, the shaft should be turned 180° to present a fresh phosphated area to the loaded region of the bushing.

The current assembly has a honed rocker arm shaft bushing, a ceramic cam follower and a new phosphated (black in color) rocker arm shaft which provides improved wear characteristics. The phosphated surface is required for the proper break-in of the steel rocker arm shaft bushings.‪

Current Series 60 engines have rocker arm shafts without flats at the mounting bolt locations. For these engines, a spacer is installed between the rocker arm shaft and the mounting bolts or nuts rather than a washer. This allows the rocker arm shaft to be rotated when installing new rocker arms. When reusing rocker arm assemblies, the rocker arm shaft should not be rotated so that the same surfaces of the rocker arm assemblies and rocker shafts are in contact with each other.‪

Vertical oil passages at the front and rear of the cylinder head deliver oil from the cylinder block front and rear oil galleries to the No. 1 and 7 lower camshaft bearing saddles. From there, the oil is directed upward (through the enlarged stud hole) to the No. 1 and 7 upper bearing caps. A drilled passage in each of these caps exits at the rocker arm shaft seat area, where it indexes with a hole in each rocker arm shaft.‪

The rocker arm shafts have internal oil passages that deliver oil to the rocker arm bushings and intermediate upper camshaft bearings. Some of the oil supplied to the rocker arm bushings passes through the oil hole in the bushing to the rocker arm assemblies. The rocker arm assemblies contain drilled passages that supply oil to the camshaft roller follower, the roller pin and the bushing. The rocker arm assemblies also contain drilled passages that supply oil to the unitized valve adjusting screw assembly and exhaust valve stems and the fuel injector follower. ‪

Note: In December 2000, a new unitized adjusting valve screw assembly now replaces the former valve adjusting screw, valve button and retainer clip.

The No. 4 camshaft cap is "Y" drilled, forming an oil path connection between the front and rear rocker arm shafts, to ensure complete lubrication. The oil passage within one rocker arm cylinder set is shown. See Figure "Rocker Arm Assembly Lubrication Schematic with Former Valve Adjusting Screw Assembly" and see Figure "Rocker Arm Assembly Lubrication Schematic with Unitized Valve Adjusting Screw Assemblies" .‪

Click to see this graphic in a separate window

1. Exhaust Rocker Arm Assembly‪

4. Rocker Arm Shaft‪

2. Fuel Injector Rocker Arm Assembly‪

5. Cylinder Head‪

3. Camshaft Cap‪

6. Intake Rocker Arm Assembly‪

Figure 5. Rocker Arm Assembly Lubrication Schematic with Former Valve Adjusting Screw Assembly

Click to see this graphic in a separate window

1. Exhaust Rocker Arm Assembly‪

4. Rocker Arm Shaft‪

2. Fuel Injector Rocker Arm Assembly‪

5. Cylinder Head‪

3. Camshaft Cap‪

6. Intake Rocker Arm Assembly‪

Figure 6. Rocker Arm Assembly Lubrication Schematic with Unitized Valve Adjusting Screw Assemblies

Section 1.3.1
Repair or Replacement of Valve and Injector Operating Mechanism

To determine if repair is possible or replacement is necessary, perform the following procedure. See Figure "Flowchart for Repair or Replacement of Valve and Injector Operating Mechanism and Camshaft" .‪

Click to see this graphic in a separate window

Figure 7. Flowchart for Repair or Replacement of Valve and Injector Operating Mechanism and Camshaft

Section 1.3.2
Removal of Rocker Arm Assembly

Perform the following steps for rocker arm assembly removal:‪

Note: If unit is equipped with Jake Brake®, remove brake. Refer to "1.36.2 Removal of Model 760, 765, or 770 Jake Brake" .

Note: Jake Brakes are not used on the Series 60G engine.

  1. If necessary, steam clean the engine around the valve rocker cover and cylinder head mating area.

    Note: High pressure water or steam cleaning should be avoided in the valve rocker cover/cylinder head area of the Series 60 gas. The ignition system can be affected.

  2. Remove the valve rocker cover. Refer to "1.6.2 Removal and Cleaning of One-piece Rocker Cover For Diesel Engines Only" (one-piece), refer to "1.6.3 Removal and Cleaning of Two-piece Rocker Cover For Diesel Engines Only" (two piece), and refer to "1.6.5 Removal and Cleaning of Three-piece Rocker Cover" (three-piece).
  3. Remove the rocker arm shaft bolts (No. 2, 3, 4 or 5, 6, 7) and nuts (No. 1 or 8) that retain the rocker arm shaft assembly to the cylinder head. See Figure "Rocker Arm Shaft Bolts and Nut Identification Numbers" for Series 60 diesel engine and see Figure "Rocker Arm Shaft Bolts and Nut Identification Numbers (Series 60G Engine)" for Series 60 gas engine. For camshaft or cylinder head removal, both rocker arm shaft assemblies must be removed.

    Note: Whenever nuts No. 1 or 8 are loosened or removed, the torque on the corresponding rocker shaft stud must be checked. Torque to 126–146 N·m (93–108 lb·ft).

    Click to see this graphic in a separate window

    Figure 8. Rocker Arm Shaft Bolts and Nut Identification Numbers

    Click to see this graphic in a separate window

    Figure 9. Rocker Arm Shaft Bolts and Nut Identification Numbers (Series 60G Engine)

  4. Use rocker arm and shaft assembly removal tool (J–35996-A) to remove the rocker arm shafts, with rocker arm assemblies in place. See Figure "Rocker Arm Shaft Assembly Removal" .

    Note: Some engines may be equipped with ceramic injector rollers. Use extra caution while removing and handling.

    Click to see this graphic in a separate window

    Figure 10. Rocker Arm Shaft Assembly Removal

  5. Remove unitized valve adjusting screw assemblies. Then proceed to step 7 .

    Note: If the unitized valve button separates from the screw, the button and screw must be replaced with a new Unitized Valve Adjusting Screw assembly. Do not attempt to reassemble them for reuse in engine. Unitized Valve Adjusting Screws will not be serviced separately.

    Note: If removing a former valve adjusting screw with valve button and retainer clip, proceed to step 6 .

  6. To remove the valve button or valve button retaining clip, the valve adjusting screw must be removed from the rocker arm as follows:

    NOTICE:

    To avoid possible component damage, the valve button retainer MUST NOT be expanded more than 15.5 mm (0.610 in.). An adjusting screw is provided on the expander tool to limit the amount of travel.‪

    1. Spread the retaining clip with expander and remove the button. See Figure "Valve Button Retainer Clip Removal" .
    2. Click to see this graphic in a separate window

      Figure 11. Valve Button Retainer Clip Removal

    3. Slide the retaining clip, open end first, down the adjusting screw. It is necessary to spread the clip slightly so that the open end can pass over the ball head of the adjusting screw.
    4. Insert the tips of the expander (J–36347) between the legs of the retaining clip and expand the clip.
    5. Insert the groove on the valve button into the legs of the retaining clip.
    6. Remove the expander and hold the legs of the retainer with the thumb and index finger.
    7. Press the valve button towards the screw to seat both legs of the retainer completely in the groove.
  7. If further disassembly is necessary, slide the rockers off the shafts, marking or segregating the parts so that they may be reinstalled in the same position from which they were removed.

    Note: Front and rear rocker arm shaft sections look identical, but must not be reversed, and must be installed as removed, due to bolt hole center line distances. The DDC logo is stamped on the outboard end of each rocker shaft to ensure correct assembly and installation. See Figure "Rocker Arm Shaft Identification Mark" .

    Click to see this graphic in a separate window

    Figure 12. Rocker Arm Shaft Identification Mark

Section 1.3.2.1
Cleaning of Rocker Arm Assemblies

Clean the rocker arm assemblies as follows:‪

  1. Remove the cup plug at one end of the rocker arm shafts to facilitate the removal of any foreign material lodged behind the plug.

    NOTICE:

    Do not soak the rocker arms in solvent because this will remove the lubricant from the cam follower roller bushings.‪

  2. Clean the exterior of the rocker arms only.
    warning

    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 276 kPa (40 psi) air pressure.‪

  3. Blow dry with compressed air.
  4. Soak the rocker shaft in clean fuel oil.
  5. Run a wire brush through the oil passage to remove any foreign material or sludge.
  6. Clean the exterior of the shaft and blow out the passages and oil holes; and dry with compressed air.
Section 1.3.2.2
Inspection of Rocker Arm Assemblies and Camshaft Lobes

Prior to inspection: ‪

  1. Install new cup plugs with installer tool (J–36326) until they are 1.0-1.3 mm (0.040-0.050 in.) below the surface of the shaft. See Figure "Rocker Arm Shaft Identification Mark" .
    Click to see this graphic in a separate window

    Figure 13. Rocker Arm Shaft Identification Mark

  2. Remove all of the old gasket sealer from the joint face of the Number 1 and Number 7 camshaft bearing caps and the cylinder head. Refer to "Gasket Eliminator Removal" in the "General Information" section.

Inspect the rocker arm assemblies and camshaft lobes as follows:‪

  1. Inspect the rocker arm shaft bushing surfaces and rocker arm bushing bores.
    1. Check the rocker arm shaft bushing surfaces and rocker arm bushing bores for wear or scoring. If damage was found, replace component.
    2. If no damage was found, reuse component.
  2. Inspect the cam follower rollers.
    1. Check the cam follower rollers for scoring, pitting, or flat spots. If damage was found, replace the component.
    2. If no damage was found, reuse component.
  3. Check the cam follower rollers to ensure they turn freely on the roller pins.
    1. Clearance between the rollers and pins should not be more than 0.08 mm (0.003 in.).
    2. Replace as necessary.
  4. Inspect the camshaft lobes and journals.
    1. Check the camshaft lobes and journals for scoring, pitting, or flat spots. If damage was found, replace the component.
    2. If there is doubt as to the acceptability of the camshaft for further service, determine the extent of camshaft lobe wear. Refer to "1.28.3.1 Inspection of Camshaft and Camshaft Bearing" .
  5. Inspect the valve adjusting screw assemblies.
    1. If former style valve adjusting screw assembly is damaged; replace with new unitized valve adjusting screw assembly.

      Note: Replace with unitized valve adjusting screw assembly of the correct position.

    2. If any damage is found on the unitized valve adjusting screw assembly; replace with new unitized screw assembly.
    3. If no damage is found on the former style valve adjusting screw or on the new unitized valve adjusting screw assembly; reuse the components.

      Note: Former style valve adjusting screw assemblies and the unitized valve adjusting screw assemblies are interchangeable and can be mixed in the same engine.

Section 1.3.3
Installation of Rocker Arm Shaft Assembly

Perform the following for rocker arm shaft assembly installation:‪

  1. Ensure the cup plugs are properly installed to each end of the rocker arm shafts before the shafts are installed to the engine. See Figure "Rocker Arm and Related Parts" . Refer to "1.3.2.2 Inspection of Rocker Arm Assemblies and Camshaft Lobes" , step 1 .
    Click to see this graphic in a separate window

     1. Unitized Valve Adjusting Screw Assembly; Intake‪

     5. Rocker Arm Shaft‪

     2. Locknut‪

     6. Unitized Valve Adjusting Screw Assembly; Exhaust‪

     3. Intake Rocker Arm Assembly‪

     7. Exhaust Rocker Arm Assembly‪

     4. Fuel Injector Rocker Arm Assembly‪

     8. Unitized Valve Adjusting Screw Assembly; Injector‪

    Figure 14. Rocker Arm and Related Parts

  2. Check the torque on the rocker shaft studs to ensure they were not loosened when the nuts were removed. Torque the studs to 101-116 N·m (75-86 lb·ft).
  3. Install the unitized valve adjusting screw assemblies to the rocker arm assemblies. See Figure "Rocker Arm and Related Parts" .

    Note: There are three different unitized valve adjusting screw assemblies. Ensure the correct unitized valve adjusting screw assembly is used in the correct location. See Figure "Unitized Valve Adjusting Screw Assemblies (Exhaust, Injector and Intake)" .

    Note: Former style valve adjusting screw assemblies can be mixed with new unitized valve adjusting screw assemblies.

    Click to see this graphic in a separate window

    Figure 15. Unitized Valve Adjusting Screw Assemblies (Exhaust, Injector and Intake)

  4. Install the rocker arm assemblies to the rocker arm shafts in their original positions. Use the rocker arm identification marks to ensure correct component assembly. If the rocker arm shaft does not have flats, decide on the position of the worn surfaces and rotate the rocker shaft accordingly.
  5. Using care to locate the valve button of the unitized valve adjusting screw assemblies to their respective valve stems and injector followers, install the rocker arm shaft assemblies to the cylinder head. See Figure "Rocker Arm Shaft Assembly Installation" .
    Click to see this graphic in a separate window

    Figure 16. Rocker Arm Shaft Assembly Installation

  6. If the rocker arm shafts do not have flats in the bolt hole locations, rocker shaft spacers are required.
    1. If the rocker shafts do not have flats in the bolt hole locations, install the rocker shaft spacers on the cap bolts and studs.
    2. If the rocker shafts do have flats in the bolt hole locations, rocker shaft spacers are not required.
  7. Install the inboard camshaft cap bolts for each rocker arm assembly, through the rocker arm shaft and camshaft cap and into the cylinder head.
  8. Install the nuts to the No. 7 and 8 cap studs.

    Note: If new rocker arm components are installed, engine oil should be poured over the rocker arms, rocker shaft, and camshaft as a pre-lubricant.

  9. Torque the rocker arm shaft nuts to 101-116 N·m (75-86 lb·ft) using the sequence. See Figure "Rocker Arm Shaft Retaining Bolt and Nut Tightening Sequence" .
    Click to see this graphic in a separate window

    Figure 17. Rocker Arm Shaft Retaining Bolt and Nut Tightening Sequence

  10. Adjust the intake and exhaust valve clearances and set the injector heights. Refer to "13.2 Valve Lash, Injector Height (Timing) and Jake Brake® Lash Adjustments" .
  11. Install the valve rocker cover. Refer to "1.6.8 Installation of One-Piece Rocker Cover" (one-piece), refer to "1.6.9 Installation of Two-Piece and Three-Piece Rocker Covers" (two-piece) and (three-piece).
  12. Install any other components that were removed for this procedure.
    warning

    PERSONAL INJURY

    Diesel engine exhaust and some of its constituents are known to the State of California to cause cancer, birth defects, and other reproductive harm.‪

    • Always start and operate an engine in a well ventilated area.
    • If operating an engine in an enclosed area, vent the exhaust to the outside.
    • Do not modify or tamper with the exhaust system or emission control system.
  13. Start the engine and check for leaks. Shut down the engine when completed.


Series 60 Service Manual - 6SE483
Generated on 10-13-2008

Leave a Reply

Your email address will not be published. Required fields are marked *