Recommended Starter Duty Cycle - Cessna 172S Skyhawk Information Manual

SECTION 4
NORMAL PROCEDURES
CESSNA
MODEL 172S
Should the engine tend to die after starting, turn on the auxiliary
fuel pump temporarily and adjust the throttle and/or mixture as
necessary to keep the engine running. In the event of over priming
or flooding, turn off the auxiliary fuel pump, open the throttle from
1/2 to full open, and continue cranking with the mixture full lean.
IWhen the engine starts, smoothly advance the mixture control to full
rich and retard the throttle to desired idle speed.
If the engine is under primed (most likely in cold weather with a
Icold engine) it will not start at all, and additional priming will be
necessary.
I After starting, if the oil pressure gage does not begin to show
pressure within 30 seconds in the summer time and approximately
one minute in very cold weather, stop the engine and investigate.
Lack of oil pressure can cause serious engine damage.
NOTE
Additional details concerning cold weather starting and
operation may be found under COLD WEATHER
OPERATION paragraphs in this section.
I
RECOMMENDED STARTER DUTY CYCLE
Crank the starter for 10 seconds followed by a 20 second cool
down period. This cycle can be repeated two additional times,
followed by a ten minute cool down period before resuming
cranking. After cool down, crank the starter again, three cycles of
10 seconds followed by 20 seconds of cool down. If the engine still
fails to start, an investigation to determine the cause should be
initiated.
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Revision 4