Chevrolet Fleetmaster Series 1947 Owner's Manual page 53

If you anticipate that the lowest
use the grade indicated
atmospheric temperature will be
Not lower than 32° F. 20-W or S.A.E. 20
As low as plus 10° F. 20-W
As low as minus 10° F. lO-W
Below minus 10° F. 10-W plus 10% Kerosene
lO-W oil 'plus 10% kerosene is recommended only for those
territories where the temperature falls below 10 degrees below
zero for protracted periods. -
Fig. 41 shows the data in the above table as it would appear
on a thermometer-the lowest temperature at which the indicated
grades of oil will permit easy starting.
NOTE: When in doubt, use the lighter grade of oil. We recommend the use of
20- W rather than S.A.E. 20 if you anticipate temperatures to drop to freezing.
Summer-
The use of 20-W or S.A.E.
20 oils during the summer months will permit better all-around
performance than will the heavier body oils, with no appreciable
increase in oil consumption.
If S.A.E. 20 or 20-W oil is not available, S.A.E. 30 oil may be
used if it is expected that the average
prevailing daylight temperature will
consistently be above 90° F.
Maintaining Oil Level-The
Oil
Level Rod (Fig. 42) is marked "Full"
or "Add Oil." These notations have
broad arrows pointing to the level
lines.
The oil level
sho~ld
be maintained
between these two lines; neither going
over the "Full" line nor under the
"Add Oil" line.
Check the oil level frequently and
add oil when necessary. Always be
sure th~ crankcase is full before start-
ing on a long drive.
Fig. 42-0il Level
Rod in Pan
Oil Pressure Gauge-
When starting
a cold engine, it will be noted that the oil pressure gauge on the
instrument panel will register a high oil pressure. As the engine
warms up, the pressure will drop until it reaches a point where
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