TM-9-2815-200-35 Maintenance Manual for AVDS-1790-2M AVDS-1790-2A and AVDS-1790-2AM Engines Download
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6-8 (1) Removal. Drill out bearing retaining pins when used to secure bearings in castings or retaining cages when applicable. (2) Installation. (a) Aline bushing, liner, or bushing-type bearing in casting or retaining cage. Press into place with a suitable pressing arbor. (b) Select proper drill size for installation of bearing retaining pins. Drill through bearing and into casting or retaining cage to the proper depth so that the pin will be flush with the bearing surface after installation. Drive retaining pin through bearing and into casting or retaining cage. Cut off any portion of pin that extends above bearing. (c) Ream or burnish bushing liner, or bushing-type bearing to size specified in ap- propriate overhaul standards table. (d) Clean repaired parts thoroughly before assembly or installation. j. Oil Seals. Replace all oil seals at engine overhaul. During field repair, replace oil seal when thin feather edge is damaged or when seal has become hard or brittle. (1) Removal. Press or pry damaged oil seal from casting or adapter, being careful not to damage bore in casting or adapter. (2) Repair. When oil seal bore in casting or adapter is burred or damaged to a point where an oil-tight seal is impossible, repair or replace casting or adapter. Remove slight nicks, burs, and scratches from oil seal bore in casting or adapter with crocus cloth dipped in dry-cleaning solvent or mineral spirits paint thinner. (3) Installation. Install new oil seal in bore of casting or adapter. 6-5. Replacement of Helical-Coil and Threaded Inserts a. General. Replace all helical-coil and screw thread inserts which do not fit securely in the casting or when casting threads have become galled or stripped. b. Replacement. Replace all unserviceable helical-coil and screw thread inserts in the same manner, following instructions which accompany figures 6-2 and 6-3. For instructional purposes helical-coil inserts in the cylinder assembly will be replaced. 1. Use a diamond-shaped punch is the insert (A) is the serrated-teeth type to drive staked, serrated-teeth section of insert from the thread in cylinder casting. 2. Install screw thread extractor - 5120-251-1527 into insert. Remove insert by applying constant pressure while turning extractor (B) counterclockwise until insert is removed. Figure 6-2. Removing helical-coil threaded insert from cylinder assembly using screw thread extractor-5120-251-1527.5