TM-9-2520-234-35 Technical Manual for M109 Transmission XTG-411-2A Download

PAR 71-72 PRELIMINARY INSTRUCTIONS FOR CHAP 5, SEC I POWER TRAIN OVERHAUL WARNING Dry Cleaning Solvent P-D-680 is toxic and flammable. To avoid injury, wear protective goggles and gloves and use in a well-ventilated area. Avoid con- tact with skin, eyes, and clothes, and do not breathe vapors. Do not use near open fire or excessive heat. The flash point for Type I dry cleaning solvent is 100°F (38°C), and for Type II is 138°F (50°C). If you become dizzy while using dry cleaning solvent, get fresh air immediately and get medical aid. If contact with eyes is made, wash your eyes with water and get medical air immediately. (1) Every component should be thoroughly cleaned after the transmission is disassembled. Cleaning is necessary to ensure effective inspection for wear, dam- age and serviceability of components. (2) Abrasives, files, scrapers, wire brushes and sharp tools should never be used on surfaces where finish is impor- tant to the operation or sealing of parts, except where specifically recommended. (3) Gum or varnish deposits may be removed by soaking in dry cleaning solvent or mineral spirits and using a soft-bristle brush. Crocus cloth may be used to remove minor surface irregulari- ties. Lapping compound may be used, if required, in valve body bores to prevent valves from sticking. Clean thoroughly to remove compound after use. (4) A soft wire (brass or copper) may be used to clean oil passages. Always flush such passages thoroughly after clean- ing. (5) If steam cleaning is used, dry the cleaned parts immediately with com- pressed air and apply a film of oil to pre- vent rusting. Never use lye or caustics which will corrode or etch metal surfaces. (6) Do not clean the lubricant from new bearings. Keep new bearings wrapped until they are to be installed. Soak bearings which have been in service in dry cleaning solvent or mineral spirits to loosen deposits of dirt. Do not spin the bearings during cleaning or drying. After cleaning, turn the bearings by hand and note any evidence of grit. Reclean them if grit is present. Refer to TM 9-214 for further information on cleaning bearings. 72. INSPECTION AND REPAIR RECOMMENDATIONS Note. Just before or during assem- bly, lubricate all seals, shafts, gears, bearings, valves, and other moving parts with transmission oil. This lubrication will protect the parts during storage and at initial start-up. a. Castings, Forgings, Machined — Surfaces (1) Inspect all castings and forg- ings for breaks, cracks and wear or scoring that would impair serviceability. Remove nicks and small surface irregularities with crocus cloth or a soft stone. (2) Inspect all oil passages for obstructions and dirt. Reclean passages if necessary. (3) Inspect mounting faces for nicks, scratches and scores. Remove minor defects with crocus cloth or a soft honing stone. Replace any parts in which defects that cannot be corrected will impair the operation of the transmission. (4) Inspect threaded openings for damaged threads. Chase damaged threads with the correct size used tap. Note. A new tap will cut oversize. If threads are stripped, discard the part unless it can be satisfactorily repaired by installing an insert. (5) Replace housings or other cast parts that are cracked or broken. b. Roller or Ball Bearings. Refer to TM 9-214 for proper cleaning and inspec- tion procedures. c. Needle-type Roller Bearings. In- spect the bearings for free and smooth rotation, broken or missing rollers, and Change 2 75