TM-9-2815-220-34 Direct Support Manual for AVDS-1790-2C and AVDS-1790-2D Engines Download
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TM 9-2815-220-34 fan shroud bracket mounting flange on the exhaust port side of the cylinder assembly (fig. 3-192). See table 3-12 for oversize assembly iden- tification number. T1\02161P Figure3·1\. Location of standard and oversize cylinder asembly identificatio1i numbers. Tabl 3·1$. Tabulation ofStandard and Oversize Cylinder Aasembly lde11ticatio11 Numbers Pt number 10951304 10951304·1 10951304·2 10951304-3 10951304-4 Bore size STANDARD 0.010 OVERSIZE 0.020 OVERSIZE 0.030 OVERSIZE 0.040 OVERSIZE (1) Cylinder bores may taper slightly at the head end (at room temperature). The tapered section expands and is essentially straight at operating temperature. (2) With cylinder at room temperature, take two cylinder bo re measurements at point A through E, repair standards (table 3-13) and fig. 3-193. Measure diameter approximately parallel to line of valves, and then take measurement Z de- grees to first measurement. Average the meas- urements. NOTE: ALL OIMENSIONS SHOWN E ARE IN INCHES. D A B c noTTOM I 8.25 J CF Sl<llH 6.25 9.75 10.50 TA126148I Figure 3·193. Cylinder bore dime1iona. (3) Head end average measurements must not exceed flange end average measurements. (4) Compare the measurements taken 90 de- grees apart. Each two measurements must be within 0.003 inches of each other. If the difference exceeds 0.003 inches, the cylinder is out-of-round and must be marked for repair. 3· 100 Change 2 Bore diameter 5.761- 5.753 5.761 · 5.763 5.771·5.773 5.781·5.783 5.791- 5.7] (5) Inspect ¢amshaft bearing inserts (35, fig. 3-190) r pitting, galling, burs, and nicks. Fine scratches on bearing inserts are not cause r re- jection. Pitting or any other form of destruction to . the bearing surface is cause for rejection. Spread a thin coat of Prussian blue over the backs of the bearing inserts and install in their original loca- tion on cylinder assembly and rocker box cover. Secure rocker box cover to cylinder assembly with four bolts (20) and washers (21). Torque tighten to 275-325 in. lbs. Check tne insert diameter of bear- ing inserts (35) with a dial bore indicator against the limits specified in repair standa1·ds (table 3-13). Replace bearing inserts that do not meet these requirements. (6) Inspect cylinder head and barrel cooling fins fo1· possible repair (para 3-). d. Valve Rocker Arm Cove1·s and Associated Parts. (1) Valve rocker arm cover. Inspect valve rocker support cover (15, fig. 3-190) r cracks. Inspect camshaft bearing insert surface for galling, pit- ting, burs, and nicks. Check cover against limits specified i n repair standards (table 3-13). Check valve adjusting access cover (8, fig. 3-190) for cracks and forwarpage. Replace cylinder assembly when cover is unserviceable. (2) Valve rocker arms. Inspect valve rocker arms (29 and 30) for cracks, using a magnifying glass (five power magnif ication minimum) and a strong light. Inspect the bushing-type bearing ) )