TM-9-2815-200-35 Maintenance Manual for AVDS-1790-2M AVDS-1790-2A and AVDS-1790-2AM Engines Download
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CHAPTER 4 REPLACEMENT OF ENGINE ACCESSORIES, COMPONENTS AND RELATED SERVICE OPERATIONS Section l. GENERAL 4-1. Purpose a. This chapter of the manual covers replacement of engine accessories, and removal and replacement of components related to in- spection, adjustment and service operations allocated to Direct Support maintenance per- sonnel. Some accessories, engine components or service operations can be accomplished while engine is installed in vehicle, but is dependent upon how accessible the item is. Engines which have been removed from the vehicle for ac- cessory replacement should be thoroughly cleaned before replacement of accessory is at- tempted. Refer to pertinent technical manuals for instructions on the removal or installation of the power plant and separation of the trans- mission from the engine. 4-2. Removal and Installation In- structions a. Illustrations. The illustration sequences provided in the following subparagraphs depict the procedure for removal or installation of a particular item or an adjustment and service operation. When necessary, illustrations covering variations between engine models are included to clarify any differences in disassembly or assembly procedures. b. Tables. This chapter has been grouped into sections. Each section has a contents table for easy reference for removing, cleaning, testing, installing and adjustment procedures required for a given operation and are listed by figure number under an appropriate heading in the table. c. Instructions. The step-by-step procedure to be followed for removal, installation, ad- justment, or service operation is listed im- mediately following each illustration. d. Parts Identification. Callouts will be used to point out related parts involved in the removal operation being performed. Callouts not mentioned in the instructions are related to subsequent installation procedures or are used as reference to other pertinent operations per- formed in this technical manual. Note. Parts mentioned in the instructions that accompany the operational sequence letters will be called out separately on the illustration only when required to further clarify the instructions, e. Special Instructions. (1) “Notes and Cautions”. Instructional “Notes” or “Cautions” accompany some of the illustrations and are used to further define the instructions, eliminate procedures that might result in the equipment being damaged, or injury to personnel. (2) Cleanliness. Extreme care must be exercised to insure that dust and dirt, even in minute quantities, does not enter the engine. Plug or cover all fuel and oil line connections to prevent entry of dirt. Clean parts thoroughly and coat all surfaces of bearings, shafts and contact surfaces with engine oil (OE). Surface must be protected from dirt after oiling. (3) Gaskets. Always use new gaskets and preformed packings when reinstalling engine components. (4) Torque tightening attaching hardware. All hardware must be torque tightened to specified limits. When a torque value is not specified in the text or on an illustration, refer to Standard Torque Values, para 6-7. Special torque values are specified in the text and / or illustrations. Refer also to Special Torque Values, para 6-7. Note. Do not vary from torque specified. Under-torquing will result in premature failure of studs and bolts. Over-torquing can result in yielding of bolts and studs. (5) Safety devices. All bolts and nuts must be secured with lock washers, lock nuts, tab washers, locking wire or cotter pins, as specified. 4-1