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 00-3 Change 1 dle Bearings. NOTE Bearings are MRPs and are not intended to be reused during overhaul. The following information is provided for new bearings, which may have been contaminated. (1) Bearings require special attention in cleaning and oiling. After removing surface dirt, oil or grease, the bearings, except the sealed, permanently lubricated type, may be placed in hot oil (about 150°F) to loosen congealed oil and grease. After cleaning, the bearings should be wrapped tightly in oiled or waxed paper until inspection and assembly. Do not immerse sealed type ball bearings in cleaning compound solvent or hot oil. Entrance of cleaning agent will destroy lubricants sealed in bearing at time of manufacture. WARNING Solvents can burn easily, can give off harmful vapors, and are harmful to skin and clothing. Wear protective goggles and gloves and don’t breath vapors, to avoid injury or death, keep away from open fire and use in well ventilated area. If solvent gets on skin or clothing, wash immediately with soap and water. (2) Clean sealed ball bearings by wiping the exterior surfaces with a clean cloth moistened in cleaning compound solvent. Do not use compressed air in cleaning or drying of ball or needle bearings. Damage to bearings will result from spinning of bearing by air blast. (3) Refer to TM 9-214 for information on inspection, care and maintenance of bearings. e. Painted Parts. All painted parts will be reclaimed by stripping and repainting. Rubber components must be removed and discarded before the parts can be stripped of paint. 5. Inspection. a. General. The engines covered in this NMWR are precision built with tolerances at extremely close limits. Key letters are used in the overhaul inspection procedures (OIP’s) to locate points of measurement for overhaul limits. Each section following in this chapter includes OIP’s for critical parts or components covered in the section. OIP references for such parts or components are included in the wear limits, fits and tolerances table. Where an OIP is referenced in more than one section (e.g., the same part is used on several subassemblies), the OIP is included only in the section where first referenced. To locate such OIP’s, refer to the list of overhaul inspection procedures (WP 0055 00). b. Wear Limits, Fits, and Tolerances. Each wear limits, fits, and tolerances table contains the maximum, minimum, and key dimensions of new or repaired parts. The clearances will automatically be achieved if the mating parts are within the dimensional tolerances listed in the tables. The wear limit indicates the point to which a part may be worn before replacement is required. In order to assure maximum service, all parts which have not worn beyond dimensions shown in the wear limits column and are not damaged, will normally be approved for service. 4. Clea e d. Ball and Ne ning - Continued.