Chevrolet Light - Page 37

Twice a year the radiator and cylinder block drain cocks
should be opened and all coolant removed. Using a water hose
the cooling system should then be thoroughly flushed until
the water runs clear. Then close drain cocks and refill cooling
system.
The front of the radiator core should be checked occa-
sionally for bugs, leaves, etc., which would restrict air circula-
tion. These can be flushed out 'from the back side of radiator
with an ordin _ ary water hose and city water pressure.
Maintenance-
Flushing. Scale and deposits in the cooling system which will
not flush out can generally be removed by using a good cool-
ing system cleanirig compound. When using a cleaning com-
pound in the cooling system it is advisable to follow the
instructions furnished with the particular brand of compound.
If cooling system cleaning compound will not thoroughly
clean the system it is adviSable to reverse-flush the system.
Thermostat. A faulty thermostat may cause abnormally high
or abnormally low engine temperature. If the condition of the
thermostat is questioned it can be removed and tested as
follows:
1.
Open radiator drain cock and drain out about half the
coolant, which will bring the coolant level below the thermo-
stat; close drain cock.
2. Loosen upper hose clamps and remove hose.
3. Remove the two cap screws that attach the water outlet
to the thermostat housing. Remove water outlet, gasket and
thermostat.
4. Heat a container of water to a temperature 25 ° above
the temperature stamped on the thermostat and place thermo-
stat in the water and see if it opens fully.
5. Place thermostat in water 10° below the temperature
stamped on th e rmostat and s ee if thermostat fully closes.
6. If the thermostat does not fully open on test in Item 4 or
fully close on test in Item 5, it should be replaced.
7. Place thermostat in housing, install water outlet using a
new gasket, install attaching screws and tighten them evenly
and securely.
8.
Inspect the upper hose and if necessary replace it. Install
the hose and tighten hose clamps securely.
9. Fill cooling system and check it for leaks.
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