Cooling System Care - Chevrolet Impala 1969 Owner's Manual

as the last step in a fuel stop. This will
allow the oil accumulation in the en-
gine to drain back in the crankcase.
To check the level. remove the oil
gauge rod (dip stick), wipe it clean
and reinsert it firmly for an accurate
reading. The oil gauge rod is marked
"FULL" and "ADD." The oil level
should be maintained in the safety
margin, neither going above the
"FULL" line nor below the "ADD"
line. Reseat the gauge firmly after tak-
ing the reading.
NOTE: The oil gauge roc! is also marked
"Use GM 6041-M Quality MS Oil" as a
reminder to use only high quality oils
as
prescribed·under "Engine Oil Recommen-
dations".
Cooling System Care
Check the coolant level at each en-
gine oil change. Level should be I"
below bottom of filler neck when cold.
The inhibited year-around engine
coolant, used to fill the cooling system
at the factory is a high quality solution
that meets General Motors Specifica-
tion 1899-M. This factory-fill coolant
solution is formulated to withstand
two full calendar years of normal op-
eration without draining or adding
inhibitors, provided the same concen-
tration of coolant is added if the
system needs additional fluid between
drain periods. The original factory fill
coolant provides freezing protection to
-20°F. (-32° F. in Canada).
Every two years, the cooling system
should be serviced as follows:
1. Drain coolant, when hot, through
the radiator drain valve.
2. Close valve and add sufficient plain
water to fill system.
3. Run engine until normal operating
temperature is reached.
4. Drain and refill the system as de-
scribed in steps 1, 2, and 3 a suffi-
cient number of times until the
drained liquid is colorless.
5. Allow system to drain completely
and then close radiator drain valve
tightly.
6. Add the necessary amount of high
quality inhibited glycol base cool-
ant meeting GM Specification
1899-M to provide the required
54
freezing and corrosion protection
(at least to O°F.)
7. Run engine until normal operating
temperature is reached.
8. Check and adjust level of coolant
after system has cooled sufficiently
to remove radiator cap.
It is the owner's responsibility to
keep the freeze protection at a level
commensurate with the temperatures
which may occur in the area in which
the vehicle will be operated. Regard-
less of whether freezing temperatures
are or are not expected, cooling sys,..
tern protection should be maintained
at least to O°F. to provide adequate
corrosion protection.
When coolant additions are required
because of coolant loss or to provide
additional protection against freezing
at temperatures lower than -20°F,
(-32°F in Canada), a sufficient
amount of an ethylene glycol base
coolant meeting GM Specification
1899-M should be used.
NOTE: Alcohol or methanol base cool-
ants or plain water are not recommended
for your Chevrolet at any time.