TM-9-2815-237-34 HMMWV Engine Direct Support & General Support Maintenance Manual Download
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TM 9-2815-237-34 c. Bearings. CAUTION All engine connecting rod and main bearings will be replaced if one or more bearings fail. Check all bearings for conformance to applicable repair standards. d. Bushings and Bushing-Type Bearings. (1) Check all bushings and bushing-type bearings for secure fit, evidence of heating, wear, burrs, nicks, and out-of-round conditions. from e. f. g. h. i. j. (2) Check for dirt in lubrication holes or grooves. Holes and grooves must be clean and free damage. Machined Parts. (1) Check machined parts for cracks, distortion, and damage. (2) Check all surfaces for nicks, burrs, and raised metal. Studs, Bolts, and Capscrews. Replace if bent, loose, stretched, or threads are damaged. Gears. NOTE When gear teeth wear limits are not established, good judgment is required to determine if gear replacement is necessary. (1) Inspect all gears for cracks and missing teeth. Replace if cracked or teeth are missing. (2) Inspect gear teeth for wear, sharp fins, burrs, and galled or pitted surfaces. (3) Inspect splines for wear, burrs, and galled or pitted surfaces. (4) Check keyway slots for wear and/or damage. Oil Seals. Oil seals are mandatory replacement items. Casting Plugs. Inspect for leakage. Replace plugs when leakage is present. Springs. Inspect for damaged, distorted, and collapsed coils. Snaprings, Retaining Rings, and Washers. Many of these parts are mandatory replacement k. items. Inspect all others for obvious damage. 2-11. REPAIR a. General Instructions. Repair of most parts and components is limited to general procedures outlined in applicable maintenance instructions and the following detailed procedures “b” through “h”. CAUTION Repaired items must be thoroughly cleaned to remove metal chips and abrasives to prevent them from entering working parts of the engine. b. Castings. (1) All cracked castings will be replaced. (2) Only minor repairs to machined surfaces, flanges, and gasket mating surfaces are permitted. Remove minor nicks, burrs, and/or scratches with: (a) Fine mill file. (b) Abrasive crocus cloth dipped in cleaning solvent. (c) Lapping across a surface plate. (d) Remachining of machined surfaces to repair damage, warpage, or uneven surfaces is not permitted. Replace castings. (3) Repair damaged threaded pipe plug and/or capscrew holes with a thread tap or repair oversize holes with threaded inserts. 2-5