NMWR-9-2815-220 Overhaul Manual for M60 M88 Engine AVDS-1790-2CA, AVDS-1790-2DA, AVDS-1790-2DR Download
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NMWR 9-2815-220 CRANKSHAFT AND ASSOCIATED PARTS OVERHAUL—Continued 0008 00 REPAIR 1. Refer to WP 0005 00 for general repair instructions. 2. Crankshafts that are worn beyond standard wear limits specified in the OIP Table 2, or with journal or crank pin damage may be ground undersize to the limits listed in Table 2. 3. If any of the crank pins or journals are found unserviceable, it will be necessary to grind all crank pins or journals uniformly undersize to maintain the balance of the crankshaft. Extreme care must be taken when grinding to maintain the concentricity of the entire crankshaft and not to exceed a surface roughness of 12 micro inches. All radii on the crank pins and journals, affected by grinding undersize, must be re-established to original configuration. The crankshaft crank pins and journals must be inspected by magnetic particle, or similar method, for fractures and surface cracks after grinding. 4. Replace dowel pins and straight pins in crankshaft flanges if pins do not fit securely in flange, are out-of-round, or if pins do not conform to limits specified in the OIPs. If applicable, grind pins (crankshaft end) to standard size, thus eliminating the reaming of the crankshaft flange. NOTE The headless grooved dowel pins in the flywheel are available in 0.005 in. (0.127 mm), 0.010 in. (0.254 mm), and 0.015 in. (0.381 mm) oversize. Grind the crankshaft end of the oversize dowel pins to standard size, no less than 0.6255 in. (15.887 mm), instead of reaming the mounting flange holes. 5. Replace a cracked crankshaft or a crankshaft showing evidence of wear due to bent or twisted connecting rods. ASSEMBLY 1. Refer to WP 0005 00 for general assembly procedures. 2. Assemble crankshaft and associated parts in accordance with TM 9-2815-220-34. 0008 00-5