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 GENERAL MAINTENANCE, OVERHAUL, AND REPAIR PROCEDURES—Continued 0005 00 0005 00-7 Change 1 7. Replacement of Screw Thread Inserts. a. General. Replace all screw thread inserts which do not fit securely in the casting or when casting threads are galled or stripped. b. Replacement. Replace all unserviceable screw thread inserts in the same manner as outlined in step (1) below. For instructional purposes screw thread inserts in the engine crankcase assembly will be replaced. Use a diamond-shaped punch to remove the staked, serrated-tooth type section of insert from the thread in the engine component parent metal. 8. Assembly. a. General. Extreme care must be exercised in all assembly operations to insure satisfactory engine performance. General rules for assembly are outlined below. Procedures for assembling the various components are covered in the paragraph relating to the specific component. b. Precautionary Rules. (1) Cleanliness is essential in all assembly operations. Dirt and dust, even in minute quantities, are abrasive. Parts must be cleaned as specified and kept clean. Wrap or cover parts and components when assembly procedures are not immediately completed. (2) Coat all bearings, shafts, and all contact surfaces with oil (OE) to insure lubrication of parts during initial assembly. (3) Always use new gaskets and preformed packings when assembling engine and engine subassemblies. (4) Use flat washers under all lockwashers, nuts, and bolts to protect any aluminum surfaces. (5) Most bolts, cap screws, and nuts must be secured with lockwashers, tab washers, locking wire, or cotter pins, depending on method of locking specified. (6) Whenever a locking method is not specified for bolts and cap screws, the mid-grip helical-coil threaded inserts into which the bolts or screws are threaded serves as the locking device. (7) It is also important that all hardware be tightened to the specified torque. Refer to torque specifications in this work package.