2-19. Camshaft, Timing Chain, and Drive Gears Repair

TM 9-2815-237-34 · Chapter 2 — Engine Maintenance

This task covers:

a. Cleaning b. Inspection

INITIAL SETUP

      Tools                                                Equipment Condition
        General mechanic’s tool kit:                         Engine disassembled into subassemblies
         automotive (Appendix E, Item 1)                     (para. 2-15).
        Micrometer (Appendix E, Item 16)
        “V” blocks (Appendix E, Item 21)
        Dial indicator (Appendix E, Item 10)
      Manual References
        TM 9-2815-237-34P

      a. Cleaning

 Clean all components in accordance with para. 2-9.
b. Inspection

                                                       NOTE
                          ● For general inspection instructions, refer to para. 2-10.
                          ● All lifters must be replaced when replacing camshaft.

 1.      Inspect camshaft bearing journals (7) and lobes (8) for damage. Replace camshaft (6) if damaged.
 2.      Measure diameter of bearing journals (7) using outside micrometer. Replace camshaft (6) if any
         bearing journal (7) is out of specification (table 2-2 or 2-3).
 3.      Support camshaft (6) on "V" blocks.
 4.      Using dial indicator and “V" blocks, measure cam lobe (8) lift. Replace camshaft (6) if any cam
         lobe (8) is out of specification (table 2-2 or 2-3).
 5.      Inspect crankshaft sprocket (9), camshaft sprocket (3), pump drive gear (10), and pump driven
         gear (1) for damage. Replace any gear or sprocket if damaged.
 6.      Inspect timing chain (2) for cracks, breaks, or binding. Replace if cracked, broken, or binding.
 7.      Inspect camshaft thrust plate (4) and spacer (5) for damage. Replace if damaged.