GENERAL MAINTENANCE PROCEDURES (Contd)
a. General Instructions. Procedures for inspections will be the same for many parts and components
which make up the vehicle subassemblies. General procedures are detailed in steps b through q.
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.
(1) Inspect all ferrous and nonferrous castings for cracks using a magnifying glass and strong light.
(2) Refer to ASTM-E 1417, Inspection, Liquid Penetrant Methods, and MIL-I-6868, Inspection
Process, Magnetic Particles.
(3) Particularly inspect areas around studs, pipe plugs, threaded inserts, and sharp corners. Replace
all cracked castings.
(4) Inspect machined surfaces for nicks, burrs, or raised metal. Mark damaged areas for repair or
(5) Inspect all pipe plugs, pipe plug openings, screws, and screw openings for damaged or stripped
threads. Replace or repair damaged or stripped threads.
(6) Using a straightedge or surface plate, check all gasket mating surfaces, flanges on housings, and
supports for warpage. Inspect mating flanges for discolorations which may indicate persistent
oil leakage. Replace damaged parts.
(7) Check all castings for conformance to applicable repair standards. Replace damaged castings.
applicable repair standards.
d. Studs, Bolts, and Screws. Replace if threads are damaged, bent, or stripped.
(1) Inspect all gears for cracks in strong light. No cracks are allowed.
(2) Inspect gear teeth for wear, sharp edges, burrs, and galled or pitted surfaces.
(3) Check keyway slots for wear and/or damage.
f. Oil Seals. Oil seals are mandatory replacement items.
g. Engine Bearings.
Engine connecting rods and main bearings are serviced in sets. If
one bearing fails, all bearings must be replaced.
Old and new style engine components must be used as sets and
h. Bushings and Bushing-Type Bearings.
(1) Check all bushings and bushing-type bearings for secure fit, evidence of overheating, wear,
burrs, nicks, and out-of-round condition.
(2) Check for dirt in lubrication holes or grooves. Holes and grooves must be clean and free from
Expansion Plugs. Inspect for leakage. Replace plugs when leakage is present.
Machined Tooled Parts. Inspect for cracks, breaks, elongated holes, wear, and chips.
k. Machined Surfaces. Inspect for cracks, evidence of wear, galled or pitted surface, burrs, nicks, and
Mated Surfaces. Inspect for remains of old gasket, seal, secure fit, pitting, and evidence of leakage.