1935 Cadillac - GM Heritage Center

75
COOLING SYSTEM
Second-type thermostats can he identified by
the number 31-10 stamped on the outer flange,
whereas the first type were numbered 30-99. Any
thermostats stamped with both of these numbers
have been reworked into the second type, and
are therefore satisfactory for use.
In cases of serious complaint of loss of volatile
anti-freeze by boiling on cars prior to the above
engine numbers, the second-type thermostat
should be installed. This thermostat will correct
the condition except when very strong solutions
of alcohol or methanol are used. Solutions strong
enough to protect down to below zero will evaporate
under hard driving even with the second-type
thermostat. For very low temperatures, a permanent
anti-freeze should be used.
Whenever a second-type thermostat is installed
in place of a first type, an identifying ring of
white paint should be marked on the radiator
upper tank around the right inlet pipe by the
filler neck. Replacement of the thermostat is
accomplished in the following manner:
1. Remove radiator casing as explained in
Note 10.
2. Remove the old radiator thermostat.
3. Install the new thermostat, and test for
operation at the correct temperature.
4. Install radiator casing as explained in
Note 10.
5. Tightening Water Pump Packing
Care should be taken in tightening the gland
nut on 355-D and LaSalle water pumps when the
fabric type of packing is used to make sure the
packing does not exert too much pressure on the
pump shaft causing it to bind. Should this occur,
the packing would soon wear out, permitting
water leakage.
In order to make sure of a proper seal, draw the
gland nut up very tight, back it off, and again
draw it up to a point where it just touches the
packing.
When replacing the packing, it is a good plan
to lubricate it slightly before installing to avoid
the possibility of its breaking up.
6. Disassembling LaSalle Water Pump
To disassemble the water pump it is necessary
first to remove it from the engine. Then remove
the fan, the pulley and the retaining nut at the
front end of the shaft, after which pull off the
fan hub. Next remove the back cover and push
the impeller and shaft out through the rear of
the housing, being sure to remove the split lock
washer (Fig. 12, Plate 23) just in front of the
gland nut. This washer is held together with a
collar and can be removed after pushing the
impeller shaft back about ^ in. An adjustable
gland nut is provided for tightening the packing
to prevent water leaks around the pump shaft.
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Outlet
"-connection
Fig. 14. The clips on the thermostat retainer in the
LaSalle cylinder head water outlet should be crimped
over the outlet connection flange to keep the retainer
in position
7. Installing Retainer in Water Outlet
Connection
When installing the thermostat retainer in the
cylinder head water outlet on LaSalle 350 cars, it
is important that the clips in the sidewalls of the
retainer be crimped over the inner flange of the
outlet connection as shown in Fig. 14. If this is
not done there is a possibility that the retainer
might shift to one-side under the connection when
installed on the engine, and prevent the outlet
from being tightened enough to prevent water
leakage. If this should occur and the cap screws
were forced, the connection might be cracked or
broken.
8. Stopping Water Leaks Around LaSalle
Cylinder Head Screws
On all except the first few LaSalle 350 cars, a
cup-shaped washer, Part No. 391798, is used
under each cylinder head cap screw. This washer
takes up some of the difference in expansion and
contraction of the metal of the head and the
screws, and helps assure a tight connection.
In case of water leakage at the cap screws on
the first few cars, this washer should be installed.
If this does not remedy the leak, it may be advisable
to replace the original cap screws with
Cadillac cylinder head cap screws, Part Number
1408707, in addition to installing the cup-shaped
washer.
9. Removing Radiator Core
The LaSalle radiator core may be removed over
the engine without disturbing the radiator casing.
This can be accomplished as follows:
1. Remove the hood, the radiator brace rods
and the carburetor air silencer.
2. Remove the water pump and the thermostat
unit.
3. Loosen the radiator core from its mounting,
the radiator casing and the lower hose connection.
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