TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
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TM 9-2615-220-34 Figure 3·143. /1+;tili11g ltelim/-c11i/ tltrcoded i11se1t ill c11li111ler c1�+1•111blu 11si11g .�·ew lltrcncl i11sertei-. 3-40. Assembly a. Geneml. Extreme care must be exercised in all assembly operations to insure satisfactory engine performance. General rules for assembly are out- lined below. Procedures for assembling the various components at·c covered in the paragraph relating to the specific component. b. Preca11lin11ary Rules. (1) Cleanlines is essential in all assembly op- erations.Dirt and dust, even in minute quantities, are abrasive. Parts must be cleaned as specified and kept clean. Wrap or cover parts and compo- nents when assembly procedures are not itn- mediately completed. (2) Coat all bearings, shafts, and all contact. surfaces with 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, capscrews, and nuts must be secured with lockwashers, tab washers, locking wire, or cotler pins, depending on method of lk- ing specified. (6) Whenever a locking method is not specified for bolts and capscrews, the mid-grip helical-coil threaded inserts into which the 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, paragraph 3-4 t. 3-41. Torque Specifications a. Sla11darcl Torquesfor Studs a11cl Boil$. Apply a light film of OE engine oil or GAA grease to studs, bolts, capscrew threads, and contact face of nuts, bolt heads, and capscrews. Avoid excessive amounts of compound in blind tapped holes. Sites (dia. in.) 1/4 5/16 3/8 7/16 1/2 9/16 3/4 Torque (lb.·in.) 15 - 100 150-175 275. 325 400-450 550. 600 800. 850 1000. 1050 b. Svecial Torques fol" Stuels a.nd Bolts. Apply a light film of OE engine oil or GAA grease to studs, bolts, capscrew threads, and contact face of nuts, bolt heads, and capscrews (except as noted). Avoid excessive amounts of compound in blind tapped holes. Crankcase Tie-rod Stud .. ... . .... 640 lb. in. Main Bearing Stud . . . .. .. ... . .. . . 450 lb. in. Crankcase Main Bearing Stud Nuts (Procedure): (1) Tighten all nuts to 500 lb. in. (2) Tighten all nuts to 700-825 lb. in. (3) Check stud stretch, i t must be 0.019 - 0.022 in. (4) Tighten nuts as necessary to obtain proper stretch. Do not exceed 0.024 stretch \vhen �dining locking wire holes. (5) All studs which exceed stretch limits at less than 700 pound-inches must be replaced.All studs which exceed the stretch limits above 700 pound- inches must be loosened and resubjected to opera- tions (1), (2), (3), and (4), above. NOTE Retorquing any singular stud is not al- lowable. The adjacent stud must also be loosened and retorqued in sequence. Componeut Torque value Accessory drive gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • • . . - . - . - • . . . 400·450 lb. in. Accessory drive housing base nuts and capscrews . . . . . . • . . . . . . . . . . . . . . . . . . . . . . • . . 27 5 lb. in. Acccsso1 drive housing lo accessory drh•e housing bnse nuts . . . ... .. . . ..... . - ........ 275 lb. in. Camshaft bevel gear and cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . 275·325 lb. in. Camsh3ft drive inner gear plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... .. . -. . . .. . 1300-1400 lb. in. Connecting rod bolt nuts - nllernatcly tighten to 100· I50 lb. in., then to 600-650 lb. in .. then to . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . 1250·1300 lb. in. Change 2 3.63 I