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TM-9-2320-280-34 HMMWV Direct Support & General Support Maintenance Manual Download

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TM 9-2320-280-34 3-10. TIMING CHAIN COVER, TIMING CHAIN, AND DRIVE SPROCKETS MAINTENANCE This task covers: a. Removal c. Installation b. Inspection INITIAL SETUP: Tools Manual References General mechanic's tool kit: TM 9-2815-237-34P automotive (Appendix G, Item 1) Equipment Condition Materials/Parts Torsional damper removed (para. 3-7). Gasket (Appendix E, Item 15) Water pump and adapter plate removed Three woodruff keys (Appendix E, Item 214) (para. 5-4). Flange sealant gasket set (Appendix B, Item 45) Maintenance Level Lubricating oil (Appendix B, Item 31) Direct support a. Removal NOTE When measuring timing chain deflection, slack should be removed from one side before measurement is taken on opposite side. In some cases, flanged head fasteners may be present instead of standard fasteners and washers. In all cases, washers should be used when replacing a flanged head fastener with a standard fastener. Perform step 1 for M997, M997A1, and M997A2 ambulance vehicles only. 1. Remove nut (5) and screw (7) from timing chain cover (6). 2. Remove three capscrews (1) and driven gear (2) from injection pump (9). 3. Remove two capscrews (18), nut (3), and baffle (4) from timing chain cover (6). 4. Remove three nuts (11) and washers (10) from injection pump (9) and timing chain cover (6). 5. Remove four capscrews (13) from timing chain cover (6) and oil pan (14). 6. Remove five capscrews (16), four washers (15), timing chain cover (6), and gasket (8) from cylinder block (12). Discard gasket (8). 7. Using dial indicator, check timing chain (23) deflection midway between camshaft sprocket (22) and crankshaft sprocket (29). Total deflection must not exceed 0.810 in. (20.6 mm). If deflection exceeds specification, timing chain (23) must be replaced. 8. Using dial indicator, check camshaft end play. Camshaft end play must not be more than 0.012 in. (0.3 mm). If end play exceeds specification, camshaft sprocket (22) and thrust plate (26) must be inspected for wear after removal. 9. Remove capscrew (19), washer (20), pump drive gear (21), and camshaft sprocket (22) from camshaft (24). 10. Remove crankshaft sprocket (29), camshaft sprocket (22), and timing chain (23) as an assembly. NOTE Cover oil pan opening to prevent woodruff keys from falling into oil pan. 11. Remove two woodruff keys (27) from crankshaft (28) and woodruff key (25) from camshaft (24). Discard woodruff keys (27) and (25). 3-20