1938 LaSalle Production - GM Heritage Center

In cases where the accumulation of rust and scale is so
great that this method does not clean the system adequately,
the system should be flushedout, using a solution of water
containing one pint of sal-soda (washing soda) and one quart
of kerosene, and running the engine for half an hour. After
this operation, the system must again be thoroughly flushed
in order to clean out all traces of this cleaning solution. Do
not allow any of the solution to reach the car finish.
Anti-Freete
Anti-freeze solutions that can be safely used are of two
types: The volatile types such as denatured alcohol and
methanol or the non-volatile types such as distilled glycerine
and ethylene glycol (Prestone).
If you prefer to use alcohol or methanol solutions, it is
important that the solution be tested at frequent intervals,
and that sufficient anti-freeze be added to replace any lost
by evaporation; otherwise there is a danger of damage by
freezing. When using these solutions, it is also important
to avoid spilling any on the car finish,or if any is spilled, to
flush off immediately with a large quantity of water.
Distilled glycerine and ethylene glycol are more expensive
in firstcost but, as they are not lost by evaporation, only
water needs to be added. Solution lost through leaking or
foaming must, of course, be replaced and on this account it
is especially important to make sure that the system is leakproof
before adding this type of anti-freeze.
Glycerine and ethylene glycol should be used in accordance
with instructions and in the proportions recommended
by the anti-freeze manufacturer. Ordinarily they should not
be mixed with other solutions. No additional rust inhibitor
should be added when the anti-freeze contains an inhibitor.
Many branded alcohol anti-freezes and most non-volatile
anti-freezes contain rust inhibitors.
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