assemble crankcase halves together, temporarily torque (P/N 64537). If the gage enters the bushing, bushing must all thru-bolts to 300 inch pounds and measure the ID of be replaced. the bearings. Measure the OD of the crankshaft main bearing journals and compare the resulting clearances 7-32. Connecting Rod Parallelism Check. See figure 7-5. with the Table of Limits (reference 501). Assemble the Using connecting rod parallelism and squareness gage connecting rods temporarily (using new bearing inserts) (P/N 64530), insert tapered sleeves (1 and 2) in bearing and check the crankpin journal clearances in the same holes in connecting rod. Be sure that bearing cap is manner, see Table of Limits (reference 502). If clearances assembled properly and securely tightened. Place arbors do not fall within prescribed limits, the shaft must be (3 and 4) through sleeves (1 and 2 respectively) and place brought undersize. See Repair and Replacement section gage arm to exact distance between arbors and lock the
for instructions for regrinding. adjusting screw with nut (7). Then remove gage arm, place
it on other end of arbor (3), and check distance between ar-7-29. Camshaft (Visual Inspection). Carefully inspect all bors. For exact parallelism or alignment, the distances surfaces of the camshaft for cracks, scoring, galling, cor-checked on both sides will be the same. See reference 566,
rosion, pitting or other damage; be particularly careful Table of Limits. when inspecting bearing surfaces. If a hydraulic lifter has been rejected for spalling, inspect the corresponding cam 7-33. Connecting Rod Squareness Check. See figure 7-6. lobe. Any indication of distress, surface irregularity or Using the same gage that was used in the parallelism feathering at the edge of the cam lobe is cause for rejec-check described above, place parallel blocks (1) on surface tion of the camshaft. plate and, with sleeves and arbors still in place in connec-
ting rod, place ends of arbor on parallel blocks. Check 7-30. Camshaft (Dimensional Inspection). Support the clearance at points (2) where arbors rest on parallel blocks, camshaft in Vee blocks at its front and rear bearing jour-using a feeler gage. For exact squareness or zero twist, no nals and check the run-out at the center bearing location. clearance will exist at the designated points. See reference See Table of Limits (reference 539). Slight bending opera-567, Table of Limits. tions are permissible on the camshaft providing careful magnetic inspection follows such procedures. Measure the 7-34. Counterweight Bushing. Wear in the counterweight diameter of the camshaft bearing journals and check them bushing is usually evident as out-of-round on the inside against the bearings formed by the crankcase. Reference diameter. Check each bushing with the bore gage P/N 537, Table of Limits. ST-73. The diameter should be between .7485 and .7505
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