TM-9-2815-205-24 Technical Manual for M113 Engine 6V53 6V53T Download
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INSPECTION-ACCEPTANCE AND REJECTION CRITERIA NOTE Overheating or burned spots on piston skirt or dome may indicate an obstruction in connecting rod oil passage. 1. Examine piston skirt and dome for score marks, cracks, damaged ring groove lands, or indications of overheating. Using a crocus cloth, remove light score marks. Replace piston skirt or dome severely scored or overheated. 2. Check cylinder liner and block bore for excessive out of round, taper, or high spots which could cause failure of piston (WP 0097). CAUTION Do not polish or refinish piston pin. Hand polishing or refinishing will destroy precision finish and result in rapid bushing wear. 3. Inspect piston pin (Figure 4, Item 20) for signs of fretting. 4. New piston pin has diameter of 1.3746–1.3750 inches (34.915–34.925 mm). Replace piston pin if worn to diameter of 1.3730 inches (34.874 mm) or less. 1.3746–1.3750 in. (34.915–34.925 mm) 20 MAINT_374 Figure 4. Piston Pin Inspection. 5. Check connecting rod for visual damage. Discard rod if bent, had previous bearing failure, was overheated (blued) at top or bottom end, is fretted at split line between rod and cap, or has excessive pound in of bolt head or nut. 6. Check for cracks by magnetic particle inspection method (reference ASTM E1444). 7. Inspect connecting rod bearing bores for burrs or foreign particles. Clean up minor burrs with crocus cloth using circular motion. TM 9-2815-205-24 0095 0095-7