TM-9-2815-202-34 Technical Manual for 8V71T Engines for M109 Howitzer Download
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TM9-2815-202-34 4-33. PISTON AND CONNECTING ROD MAINTENANCE (CROSS-HEAD) (Cent) (3) Connecting Rod (a) Check connecting rod for visual damage. Scrap rod if it is bent, had previous bearing ● failure. was overheated {blue) at to~ or bottom end, is fretted at split line between rod and cap, or has excessive pound-in of bolt head or nut. (b) Check for cracks by magnetic particle method. (gqjgg&!.,,.,.. RODS WITH INDICATIONS OVER .DD5 DEEP SECTION A-A VIEW A - A / =qg WA EXAMPLE OF A TRANSVERSE INDICATION EXAMPLE OF AN INDICATION THAT DOES NOT FOLLOW LONGITUDINAL FOLLOWING LONGITUDINAL FORGING FLOW LINES CAN SE EITHER A FORGING FLOW LINES. FORGING LAP, HEAT TREAT CRACK, OR START OF A FATIGUE CRACK. * VIEW A ~—Not+.i3,T,cALAREA-+ CRITICAL AREA ACCEPTABLE LIMITS + INDICATIONS IN NON-CRITICAL AREAS ARE ACCEPTABLE UNLESS THEY CAN BE OBSERVED AS OBVIOUS CRACKS WITHOUT MAGNETIC INSPECTION. LONGITUDINAL INDICATIONS TRANSVERSE INDICATIONS (ACROSS FLOW LINES). GRINDING NOTES FOLLOWING FORGED FLOW LINES ARE HAVING A MAXIMUM LENGTH OF 1/2, WHICH CAN BE uSUALLY SEAMS AND ARE NOT CARE SHOULD BE TAKEN IN GRINDING REMOVED BY GRINDING NO DEEPER THAN 1/64. ARE CONSIDERED HARMFUL IF LESS THAN oUT INDICATIONS TO ASSURE PROPER ACCEPTABLE AFTER THEIR COMPLETE REMOVAL 1/32 DEEP DEPTH CAN BE DETERMINED BLENDING OF GROUND AREA INTO AN EXCEPTION TO THIS ISA ROD HAVING AN BY GRINDING A SMALL AREA NEAR THE UNGROUND SURFACE SO AS TO FORMA INDICATION WHICH EXTENDS OVER THE EDGE OF W CENTER OF THE INDICATION. SM~TH CONTOUR. SECTION AND IS PRESENT ON BOTH SIDES OF THE FLANGE. IN THIS CASE, MAXIMUM ALLOWABLE ~~ DEPTH IS .005 (SEE SECTION A-A). POOR PRACTICE GOOD PRACTICE (c) Inspect connecting rod bearing bores for burrs or foreign particles. Clean up minor burrs with crocus cloth using circular motion. (d) If new connecting rod is required, stamp cylinder number on connecting rod (5) and cap (3). (4) Connecting Rod Bearings (a) (b) Inspect bearing shells for scoring, pitting, flaking, etching, and dirt grooving. If any of these defects are present, discard bearing shells. Discard bearing shells with bright spots on backs indicating movement in bearing caps or supports. 5 3 4-136