1938 LaSalle Production - GM Heritage Center

chain. Oil is conducted from the center camshaft bearing
to the hydraulic valve silencers, and thence to the cam
and valve followers.
Oil passages are drilled in the crankshaft leading oil
from each of the main bearings to the adjacent crankpins.
Part of this oil lubricates the connecting rod
bearings, part flows up the rifle drilled connecting rods
to the wrist pins and part is squirted through small
holes in the connecting rod big ends for cross lubrication
of the cylinder bores.
4
Refinements in the lubrication system for 1938 include
a removal of the oil pan drain to the left side of
the crankcase. This improves accessibility and road
clearance. A flexible oil level dip stick supersedes the
rigid stick, making oil level inspection more convenient.
Repeated experiments have shown no advantage
in the use of an oil filter for the hydraulic valve
silencer supply in the 1938 engines, consequently this
unit has been eliminated.
Crankcase
Ventilation
Cadillac engineers pioneered and developed crankcase
ventilation, and introduced it to the industry in 1925.
The engine suction type now employed is the most
thoroughly efficient method ever used and is exclusive
to Cadillac and LaSalle. Damaging unburned fuel vapors
and moisture, which would otherwise collect in the
crankcase, score cylinder walls and bearing surfaces,
and dilute lubricating quality of the oil, are positively
sucked out regardless of car speed.
Air enters through a cleaner in the top of the oil
level measuring stick, is filtered then passes through
the crankcase, picking up moisture and impurities.
These are discharged from the crankcase by one of two
openings, depending upon the engine speed. This im-
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