1938 LaSalle Production - GM Heritage Center

overflow pipe until it passes through the vent valve
with a pressure greater than three pounds per square
inch. Hence, the temperature at which the liquid mayboil
off is higher than its normal boiling point. Boilingover
action is thus forestalled completely or delayed.
The filler cap has a bayonet type fastener which
eliminates danger of pressure overflow when the cap is
removed. Before the cap can be completely turned to
removal position, any pressure built up from overheating
is allowed to escape automatically through a
vent without danger of spouting.
Wafer Pump
The impeller type water pump is easily accessible by
being built into the front of the right hand cylinder
block. An automatic packing adjustment is provided
whereby the packing is held by a regulating spring and
the .hydraulic pressure of the lubricating grease. This
prevents leakage from faulty packing adjustment and
eliminates service expense.
Wafer Circulating
System
Cadillac V-type design lends itself to more simple,
uniform cooling than is possible in straight eight
engines due to their much longer cylinder blocks.
Water is drawn through a short hose connection from
the bottom of the radiator tank to the pump. From here
it is forced under high pressure directly into the right
hand cylinder block. Half of the water passes through
the right hand block, then upward to the cylinder head.
The other half is forced through a center passage in the
engine to the left hand block. This simplified system
requires only three short hose connections.
Water pressure, provided by the size and location
of holes in the cylinder block, directly cools valve seats.
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