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 CAMSHAFT AND DRIVE ASSEMBLIES OVERHAUL—Continued 0016 00 REPAIR – Continued (2) Turn camshaft until bearing journal marked to indicate the maximum runout (high side) is adjacent to the spindle (do not press on journals). Apply spindle pressure on the camshaft until dial indicator reads approximately one half of the TIR reading recorded in (a) above. Release pressure on camshaft and recheck runout by turning camshaft several revolutions. Figure 3. Improvised Camshaft Truing Device. NOTE Pressing force required to straighten camshaft is a matter of judgement. It may be necessary to turn camshaft and apply pressing force several times in order to acquire the technique necessary to true the bearing journal. (3) Apply pressure as required until the journal is within 0.0020 (0.0508 mm) maximum TIR. (4) Reposition camshaft on supports and true other bearing journals in a similar manner. (5) After truing all bearing journals, recheck camshafts as outlined in procedure (a) above. If readings do not meet dimensions specified, repeat truing operation. (c) Inspection of camshaft after straightening. (1) Magnaflux each camshaft and inspect for cracks. Observe transition areas at bearing surfaces and at cam lobe bases. Camshafts with evidence of cracks must be discarded. (2) Inspect for damage to bearing journals. Minor nicks and scratches can be removed using crocus cloth. (3) Check bearing journals for out-of-round to be certain area was not flattened during truing. Maximum acceptable out-of-round is 0.0020 in. (0.0508 mm) (TIR). Replace camshaft if this tolerance is exceeded. 0016 00-7 Change 1