2-10. Inspection

TM 9-2815-237-34 · Chapter 2 — Engine Maintenance

a. General Instructions. Procedures for inspections will be the same for many parts and components which make up the engine subassemblies. General procedures are detailed in “b” through “k”, Dimensional standards for parts have been fixed at extremely close tolerances, so use specification tables. Use specified inspection equipment for inspection where cracks and other damage cannot be spotted visually. Exercise extreme care in all phases of inspection. Repair or replace all unserviceable components; refer to para. 2-11.

b. Castings. (1) Inspect all ferrous and nonferrous castings for cracks. See MIL-I-6866, Inspection, Penetrant Methods, and MIL-I-6868, Inspection Process, Magnetic Particles. Particularly check areas around studs, pipe plugs, threaded inserts, and sharp comers. Replace cracked castings. (2) Inspect machined surfaces for nicks, burrs, and raised metal. Mark damaged areas for repair or replacement. (3) Inspect all pipe plugs, pipe plug openings, capscrews, and capscrew openings for damaged and stripped threads. Replace if damaged or threads are stripped. (4) Check all gasket mating surfaces, flanges on housings, and supports for warpage with a straight edge or surface plate. Inspect mating flanges for discolorations which may indicate leakage. Replace if warped. (5) Check all castings for conformance to applicable repair standards.

TM page 2-5

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. (2) Check for dirt in lubrication holes or grooves. Holes and grooves must be clean and free from damage.

e. Machined Parts. (1) Check machined parts for cracks, distortion, and damage. (2) Check all surfaces for nicks, burrs, and raised metal.

f. Studs, Bolts, and Capscrews. Replace if bent, loose, stretched, or threads are damaged.

g. 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.

h. Oil Seals. Oil seals are mandatory replacement items.

i. Casting Plugs. Inspect for leakage. Replace plugs when leakage is present.

j. Springs. Inspect for damaged, distorted, and collapsed coils.

k. Snaprings, Retaining Rings, and Washers. Many of these parts are mandatory replacement items. Inspect all others for obvious damage.