condition without waiting for repair of the original. A bent crankshaft must be straightened in a hydraulic press before
grinding. If the crankshaft is ground down, undersize bearings must be installed. Undersize bearings are available in two
sizes: 0.010 and 0.030-inch undersize.
d. Installation.
(1) Press on the crankshaft gear (6, fig. 103) over the woodruff key (11) using an arbor press (par. 179). Also
press the crankshaft pulley (5) over the woodruff key (12).
(2) Install the upper bearing shells (7 and 9) in the crankcase. The bearing backs must be clean and dry. Coat
the bearing surfaces with clean engine oil OE.
(3) Support the crankshaft (8) in position under the crankcase. Mesh the timing marks on the camshaft gear (2,
fig. 105) with those on the crankshaft gear (6, fig. 103). Install the front and rear bearing caps (8 and 11,
fig. 106) and their main bearing shells (7, fig. 103) with four cap screws (9, fig. 106). Install the three center
bearing caps (10) and main bearing shells (7 and 9, fig. 103) with six cap screws (9, fig. 106). Tighten all
the cap screws to 150 foot-pounds of torque.
(4) Install the flywheel (par. 221c). Turn the crankshaft over by rotating the flywheel. No difficulty should be
experienced in turning the crankshaft over.
(5) Install the pistons, connecting rods and rings (par. 223c). Install the compressor cylinder head (par. 126c),
engine cylinder head (par. 122e), oil pans (par. 217c) and radiator and fan (par. 88b). Install the housing
(par. 130) and engine-compressor on the truck (par. 215).
223. Pistons, Connecting Rods, and Rings
a. Removal and Disassembly (fig. 104). Remove the compressor bank cylinder head (par. 126a). Remove the
engine bank cylinder head (par. 122a). Remove the lower oil pan (par. 217a). Unscrew the connecting rod bolt nuts (14)
and remove the bearing caps (1). The lower bearing shell (2) comes with the cap. Push the piston (5) through the cylinder
bore. Remove the rings (6, 7, 9, and 10) with a piston ring expander (par. 179). Remove the upper bearing shell. Do not
let it drop out of the engine. Keep the pairs of shells with their corresponding caps. Tag the pistons so they can be
returned to their original positions. Note the relative positions of the inner face of the rod and the T-slot of the piston.
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