Replace the screws if the threads are corroded, damaged, or stripped.
e. Crankshaft Runout Check.
(1) Mount the crankshaft in V shaped blocks on the front and rear main bearing journals.
(2) Insert paper strips soaked in engine oil between the bearing journals and the blocks to prevent scoring of
the journals.
(3) Take a dial indicator reading at the intermediate rear main bearing journal. If the crankshaft runout exceeds
0.002 inch, the crankshaft must be reground or replaced.
f. Crankshaft Visual Inspection. Make a careful visual inspection of the entire crankshaft, looking for scored or
damaged bearing journals, cracks, breaks, or pitting.
g. Crankshaft Magnetic Inspection.
(1) If the equipment is available, make a magnetic inspection of the crankshaft.
(2) Strongly magnetize the crankshaft by means of a magnet or pass a heavy electric current through the
crankshaft.
(3) This magnetizing will produce a flux leakage at cracks, breaks, or discontinuities in the crankshaft.
(4) Apply magnetic powder to the crankshaft; the powder will be attracted to the flux leakage areas and will form
a pattern revealing the location and extent of the damage. The magnetic powder may be applied dry by
dusting on the crankshaft, or wet by suspending it in light oil and flushing it over the crankshaft, or by
immersing the crankshaft in a bath of magnetic dust oil.
h. Bearing Inspection. Inspect all bearing shells for cracks, breaks, pitting, overheating, and abnormal wear.
Replace the bearing shells if necessary. Inspect the bearing caps for breaks and cracks and replace if necessary.
i. Reassembly (fig. 82).
(1) Install the front thrust washer (20) and thrust plate (21) on the crankshaft (19).
(2) Install the four 0.002-inch shims and seven 0.008-inch shims. This number of shims should be sufficient for
the required crankshaft end play of 0.006 to 0.004 inch.
(3) Install the oil thrower (24).
(4) Install the key (26).
(5) Push the crankshaft gear (25) on the crankshaft (19). Make sure that the key (26) and the keyway hole in
the crankshaft gear (25) are properly alined. The correct crankshaft gear fit is 1.4355 to 1.435 inch.
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