TM-9-2815-200-35 Maintenance Manual for AVDS-1790-2M AVDS-1790-2A and AVDS-1790-2AM Engines Download
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Note. The special coil screw lock inserter tools listed in special tool table 2-1 must be used when installing the self-locking thread type inserts. These special inserters are further identified by painted areas marked either with a red handle or a red stripe around the body. 1. Thread new insert (A) into the threaded guide of inserter -5120-797-2407 by slowly turning the pilot until insert is flush with the end of the tool. 2. Insert the pilot of the screw thread inserter (B) - 5120- 797-2407 into the threaded hole in cylinder, with face of the inserter resting solidly against the casting as shown. 3. Slowly turn handle (C) of pilot clockwise until no further resistance is felt. The insert will then be flush with cylinder casting. Remove inserter. Figure 6-3. Installing helical-coil threaded insert in cylinder assembly using screw thread inserter-5120-797-2407. 6-6. Assembly a. General. Extreme care must be exercised in all assembly operations to insure satisfactory engine performance. General rules for assembly are outlined below. Step-by-step procedures for assembling the various components are covered in the paragraph relating to the specific com- ponent. 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 mot immediately completed. (2) Coat all bearings, shafts, and all contact surfaces with engine oil (OE) to insure lubrication of parts during initial engine starting. (3) Always use new gaskets and preformed packings when assembling engine. (4) Use flat washers under all lockwashers, nuts and bolts to protect 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 serve as the locking device. (7) It is also important that all hardware be tightened to the specified torque. Refer to torque specifications, paragraph 6-7. 6-7. Torque Specifications a. Standard Torques for Studs and Bolts. Apply a light film of anti-seize thread compound FSN 9150-663-1770 to stud, bolt, cap screw threads, and contact face of nuts, bolt heads, and cap screws. Avoid excessive amounts of com- pound in blind tapped holes. Size Torque (dia. in.) (lb-in.) 1/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75-100 5/16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...150-175 3/8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...275-325 7/16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...400-450 1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...550-600 9/16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...800-850 b. Special Torques for Studs and Bolts. Apply a light film of anti-seize thread compound FSN 9150-663-1770 to stud, bolt, cap screw threads, and contact face of nuts, bolt heads, and cap screws (except as noted). Avoid excessive amounts of compound in blind tapped holes. Crankcase Tie-rod Bolts . . . . . . . . . . ... 640 Main Bearing Stud . . . . . . . . . . . . ...450 Crankcase Main Bearing Stud Nuts (Procedure): (1) Tighten all nuts to . . . . . . . .. 500 (2) Tighten all nuts to . . . . 700-825 (3) Check stud stretch, it must be 0.019- 0.022 in. 6-9