Chevrolet 1973 Monte Carlo Owner's Manual page 60

and in the radiator at least as fre-
quently as engine oil changes.
NOTE: Do not remove radiator
cap when coolant is hot and under
pressure.
Level should be at the "FULL
COLD" mark on the recovery tank
and at the bottom of the radiator
filler neck when the system is cold.
During normal warm weather op-
eration the coolant should be at
the "FULL HOT" mark on the re-
covery tank. If the recovery tank is
empty or coolant is below the
"FULL COLD" mark the radiator
level should be checked and cool-
ant added to the radiator and re-
covery tank as needed. Use a 50/50
mixture of high-quality ethylene gly-
col antifreeze and water for coolant
additions. If regular additions are
required see your dealer for a cool-
ing system check.
NOTE: If recommended quaIily
antifreeze is used, supplemental in-
hibitors or additives claiming to
provide increased capability are
not necessary. They may be detri-
mental to the efficient operation of
the system, and represent an un-
necessary operating expense.
Every year, the cooling system
should be serviced as follows:
1 . Wash radiator cap and filler
neck with clean water.
2. Check coolant for proper
level and freeze protection.
3. Pressure test system and radi-
ator cap for proper pressure
holding capacity (15 psi). If
replacement of cap is re-
quired, use the special AC
cap designed for coolant re-
covery systems, specified for
your car model.
4. Tighten hose clamps and in-
spect all hoses. Replace hoses
58
whenever swollen, checked or
otherwise deteriorated.
5. Clean frontal area of radiator
core and air conditioning
condenser.
Every two years or 24,000 miles,
whichever first occurs, the cooling
system should be flushed and re-
filled using the following recom-
mended procedure:
1. Run engine, with radiator cap
removed, until normal operat-
ing temperature is reached
and upper radiator hose is hot
(indicates thermostat is open.)
2. Stop engine and open radiator
drain valve to drain coolant.
(To speed this operation, the
drain plugs in the block can
also be removed.)