(3) Lift the assembled aftercooler and guard up into position with one end of the aftercooler resting on the
engine support brace (32). Insert the three studs (14), with the special nuts (18), spacers (19), spring
washers (20) and end washers (21) installed, through the mounting flanges of the aftercooler and
compressor exhaust manifold. Install and tighten the self-locking nuts (13) until the distance from the outer
spring washer on each stud to the surface of the aftercooler flange measures one inch (fig. 53).
(4) Swing the clamp (38) underneath the engine support brace (32) and tighten the hex nut (35) securely.
(5) Install the aftercooler to receiver connection (par. 116c).
Section Xll. ENGINE-COMPRESSOR
118. Description
a. The engine-compressor actually is a four-piston-engine and four-piston compressor, with all pistons connected to
a single crankshaft in a V-type crankcase. Power from the engine bank is transmitted through the crankshaft to compress
air in the compressor bank. The crankshaft is mounted in five main bearings. Full-pressure lubrication is supplied by a
gear driven oil pump mounted on the front main bearing cap. Two bypass oil filters in the lower oil pan help to keep the
lubricating oil free from foreign matter.
b. The engine and compressor banks are equipped with wet sleeve cylinders. The engine exhaust and intake
valves, are stellite faced and each has stellite inserts with positive type valve rotators to increase valve life. Above each
cylinder in the compressor cylinder head is a compressor valve assembly. Free air is admitted through the dry-type air
cleaners and through the suction valve part of the valve assembly by the action of the piston on its downward stroke.
When the piston reaches top dead center on its upward stroke (at which time the suction valve is closed), the air is
compressed and released through the discharge valve part of the assembly into the compressor discharge manifold.
119. Cylinder Head Cover and Gasket
a. Removal (fig. 54). Unscrew and remove the four hex nuts (4) and plain washers (3) from the four cover mounting
studs, and lift off the cylinder head cover (2) and gasket (1). Twist the crankcase breather (5) clockwise until it can be
lifted from the cover.
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