TM 9-2520-246-34 transmission is assembled. Mount the mainshafts in test centers and check for misalinement at bearing journals and along the entire length of the shaft by using a dial indicator. Misalinement in excess of 0.001 inch is cause for rejection. Inspect the splines and reject the shaft if splines are twisted, scored, or obviously worn. Smooth minor defects with slip stone or honing stone. Install the sliding internally splined gears on the mainshaft and clamp the mainshaft upright in a bench vise. Check each gear, in turn, for spline clearance by inserting a narrow feeler gage on edge between the splines. Refer to repair and replacement standards contained in the respective chapter for each assembly. If clearance is in excess of this established tolerance, check with a new gear and new shaft to determine whether gear splines or shaft splines are at fault. Reject the part at fault. Check wear on front and rear bearings. (11) Countershafts. Follow the same procedure, when applicable to the countershaft, as outlined above for the mainshaft. Use a honing stone to smooth out any burs, gouges, or scratches. Pay particular attention to the section of the shaft that carries the press fit gears, especially in and around the key slots. Any deviation from the normal condition in this area will cause considerable trouble when reassembling the gears on the shaft. Try the woodruff keys in the key slots. If neither the key nor the slot is distorted or misshapen, the key will require only light tapping to completely seat in the slot. Do not attempt to force the key into place; if difficulty is encountered, use a new key. (12) Input Shaft. Inspect the splines on the input shaft for wear, twisting, or galling. Inspect bearing journals for wear. Determine that the gear teeth are not cracked, broken, or otherwise damaged. (13) Shifter Fork Shafts. Check the shifter fork shafts for misalinement by rolling them across a smooth, level surface. Failure to roll, or rolling with a bumping sound, indicates misalinement. Bent or sprung shafts must be rejected, unless suitable straightening equipment is available. Inspect the shaft poppet ball detents for wear or damage. Reject the shaft if detents are chipped or are not sharply defined. (14) Poppet Balls and Springs. Reject all poppet balls with flat spots and all weak or broken springs. Use only those parts that are completely satisfactory. (15) Shifter Forks. Inspect shifter forks, paying particular attention to the lower fork ends. Bent, broken, or sprung parts are to be rejected outright, as repairs are impossible. Worn parts may be used at the discretion of the inspector. (16) Shifter Shaft Cover. Inspect shifter shaft cover for cracks or breakage. Small cracks that do not extend into the mounting holes can be repaired. Check and clean out all tapped holes; mark for repair any damaged holes or broken off studs in tapped holes. Use a honing stone to smooth out any scratches, burs, or gouges on the gasket surface. Carefully check the shifter shaft and poppet ball bores. If the shifter shaft bores are seriously scored, gouged, or galled, the cover must be rejected. Clean up minor imperfections with crocus cloth. Reject the cover if the edges of the poppet ball bores are chipped or rounded. 2-10. Repair. a. General. (1) This section contains repair instructions for the assemblies discussed in this manual. Because the material and construction are similar, the repair instructions will be given in general form. If special repair is required, refer to Cleaning, Inspection, and Repair section of the respective chapter for the assembly. (2) Only high quality repairs are acceptable. Makeshift or temporary repairs are not acceptable, except in extreme emergencies. (3) Small holes or cracks in assembly cases, shifter shaft covers, or clutch housings may be repaired by welding or brazing, provided they do not extend into the bearing bores or mounting surfaces. It should be noted, however, that these parts are cast iron. A special technique is required to satisfactorily weld this type of material; ordinary welding methods and materials are not suitable. (Refer to TM 9-237.) (4) Remove the short ends of any bolts or studs broken off in tapped holes. Clean out and inspect all tapped holes; retap where necessary. If hole threads are stripped, or if holes are out-of-round, drill out to next larger size and tap. Install a bolt or stud of the correct size to fit the newly tapped hole. b. Handling After Inspection and Repair. (1) All parts, whether new or used, must be lightly coated with lube oil (OE/HDO 30), ICE, MIL- L-2104, immediately after inspection and/or repair, prior to assembly into the transmission. Oiling the parts gives them a rust-preventive coating and facilitates the assembly operations. (2) Make sure that all new gaskets and replacement parts are available to replace those discarded. (3) Check to be sure that all parts are at hand so the assembly operations may proceed without 2-17