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NMWR-9-2815-220 Overhaul Manual for M60 M88 Engine AVDS-1790-2CA, AVDS-1790-2DA, AVDS-1790-2DR Download

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NMWR 9-2815-220 CRANKCASE ASSEMBLY OVERHAUL—Continued 0006 00 INSPECTION – Continued (d) Apply a small amount of OE 30 engine oil or GAA grease to the threaded area of each main bearing cap stud. Install a plate washer on each pair of main bearing studs. Install a slotted nut on each main bearing stud, but do not tighten nuts at this time. (e) Place a surface plate and dial indicator gage on crankcase flange with gage indicator resting on end of stud. Measure and record height of each stud. Torque tighten main bearing stud nuts to 500 lb-in. (56.5 N•m). Alternately tighten all four nuts on each main bearing to a torque of 700-825 lb-in. (79-93 N•m). Measure the height of each stud after final torque. The difference between the stud height before and after torque tightening indicates stud stretch. Normal stud stretch is 0.019 to 0.022 in. (0.4826 – 0.5588 mm). Apply additional torque to obtain a stud stretch of 0.019 to 0.022 in. (0.4826 – 0.5588 mm). Do not exceed 0.024 in. (0.6096 mm). If any stud has stretched more than 0.024 in. (0.6096 mm) at 700 lb-in. (79 N•m) torque, it must be replaced. Refer to WP 0005 00 when replacing studs. (f) Install 14 engine crankcase rods in the holes provided through the crankcase and main bearing caps. Equalize the extension of the threaded portions of the rods on each side of the crankcase. Apply a small amount of OE 30 engine oil or GAA grease to the threaded portions of each rod. Install a plate washer and a 9/16 slotted nut on each end of the rods. (g) Starting at the main thrust bearing cap, with aid of an assistant holding the nuts on the opposite side of crankcase, alternately tighten all engine crankcase rod nuts to 640 lb-in. (72 N•m) torque. (h) Check the inside diameter of the main bearing caps and the main thrust bearing cap with a dial bore indicator as shown in Figure 2 against the limits specified in Tables 7 and 8. Figure 2. Checking Inside Diameter of Main and Main Thrust Bearings. 0006 00-3 Change 1