1938 LaSalle Production - GM Heritage Center

Cooling System
The attention required by the cooling system consists of
keeping it filledto the proper level with the proper fluid,
and keeping all connections tight to insure a leak-proof
system.
The capacity of the cooling system is 25 quarts when
filled to the proper level, which is one inch below the top of the
upper tank.
Anti'Rust Treatment—When the car is delivered to
the owner, a small amount of chemical inhibitor is added to
the fluidin the cooling system, in order to reduce foaming
and retard the formation of rust and scale, thus helping to
keep the system clean. It is not necessary to add more inhibitor
each time that water or anti-freeze is added, but
whenever the cooling system is drained and refilled, a suitable
inhibitor should be added. Your Authorized Service
Station can advise you regarding the proper material to use.
Cleaning Cooling System—It is recommended that
the cooling system be thoroughly cleaned and flushedtwice
a year, or every 6,000 miles, preferably by reverse-flow
flushing. In any event, the cooling system should be cleaned
and thoroughly tightened before anti-freeze is added at the
beginning of cold weather.
The following method of cleaning the cooling system can
be used if facilities for reverse-flow flushingare not convenient.
Run the engine until it is warm; then stop the engine and
open the three drain valves for the cooling system. One
drain valve is located at the bottom of each cylinder group
and one below the water pump. All three valves must be
open to drain the engine completely. After the liquid has
drained off, refill the cooling system with hot water, run the
engine for a few minutes and again drain the system. Repeat
this operation until the water is clean when it is drained.
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