TM 9-2520-246-34 inspected to determine serviceability. Some wear or damage will be visually evident; however, it may be necessary to use tools or gages to, determine the extent of wear. The inspection procedure has two objectives: the first is to eliminate any part or parts that are unsuitable for use or doubtful parts that could conceivably cause the premature failure of the rebuilt unit; the second, and equally important, is to reduce scrapping of parts that retain a high percentage of useful life. Because the decision whether a part should be scrapped or reused is frequently a matter of judgment, this operation should be performed by personnel experienced in the maintenance of transmissions, transfers, and power takeoffs. (3) Instructions for the removal of minor imperfections and defects are included in this section because they facilitate the inspection procedure. Every part which requires it must be washed, rinsed, and dried upon completion of the repair. b. Inspection Procedure. (1) Casting. Inspect all gasket surfaces, all bearing caps and shifter shaft covers. Remove any burs, scratches, or gouges from these surfaces with a hand-honing stone. Clean all burs or foreign material from snapring grooves and expansion plug grooves. Check the cases for cracks or small pin holes, paying particular attention to areas that were marked for attention prior to initial cleaning. Cracks that do not extend into bearing bores or mounting holes may be repaired. Refer to TM 9-237 for procedures for welding or brazing cast iron. Check and clean all tapped holes. Mark any damaged holes or damaged or broken studs for repair. Try the gearshafts in the shaft bores of the cases. The shafts should be a snug fit in both the front and rear bore. If there is loose fit in any bore, try a new, unused shaft in the bore. Discard either the case or the old gearshaft, whichever is found to cause looseness. (2) Clutch Housing. Inspect the clutch housing for breaks or cracks. Small cracks that do not extend into the mounting holes may be repaired by welding. (3) Bearing Caps. Press the oil seal from the main shaft rear bearing cap, and discard the seal. Inspect all bearing caps for burs, gouges, or scratches on the gasket surface, and smooth out with hand- honing stone if necessary. (4) Gear Spacers and Thrust Washers. Replace all main shaft gear spacers, bearing spacers, and thrust washers. (5) Snaprings. Replace all snaprings. Snaprings furnished as part of ball bearings may be reused if not distorted or damaged. (6) Expansion Plugs. Replace all expansion plugs. (7) Retaining Nuts. Replace retaining nuts that have damaged threads, cuts, or cracks. (8) Gearshafts. Inspect gearshafts for gall marks or flat spots. Check gearshafts for fit as outlined in para b(1) above. Check bearing-to-shaft fit. Refer to repair and rebuild standards. Smooth any minor imperfections with crocus cloth or honing stone. Reject for any other damage. Shafts that are scored or pitted must be replaced. {9) Gears. The experience and good judgment of the inspector are required to a greater degree in judging gears than in any other operation. It is not possible to give arbitrary instructions as to when a particular condition makes a gear unfit for further use. The major and minor defects can only be pointed out, leaving the in-between scrap or salvage decision to the discretion of the individual. (a) Small nicks or burs on the engaging ends of the teeth may be removed with a small honing stone. This is only practical for minor defects. Fractures of the teeth are cause for rejection. (b) Teeth which are fractured or burred must be examined very carefully. Small burs may be removed by honing. Fractured areas, provided there are no hairline cracks radiating away from the area, may also be smoothed by honing. (c) Fractures due to metal fatigue are cause for rejection. (d) When the hubs of gears are scored, gouged, or burred seriously, the gears must be discarded. Minor imperfections may be smoothed out by honing. Excessive wear will be revealed when end play is checked during the subsequent assembly operations. (e) Examine the internal splines of all sliding gears. Twisted or broken splines are cause for rejection. Remove minor defects by honing. The inspection of splines is discussed in para (10) below. (10) Mainshafts and Output Shafts. Inspect bearing journals; reject for obvious defects such as scored or galled spots or wear beyond limits specified in the repair and replacement standards contained in the respective chapter for each assembly. Inspect threads on output end of shaft. Clean any flattened threads with a three-cornered file and wrap the threads with three or four turns of friction tape as a protective measure against further damage until the 2-16