Recommended Starter Duty Cycle - Cessna 172S Nav III Information Manual

SECTION 4 CESSNA
NORMAL PROCEDURES MODEL 172S NAV III
STARTING ENGINE (Continued)
If the engine does not continue to run, set the FUEL PUMP switch
to the ON position temporarily and adjust the throttle and/or mixture
as necessary to keep the engine running. In the event of over
priming or flooding, set the FUEL PUMP switch to OFF, open the
throttle from 1/2 to full open, and continue cranking with the mixture
in the idle CUTOFF position (pull full out). When the engine fires,
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 cold
engine) it will not start at all, and additional priming will be
necessary.
After starting, if the oil pressure gage does not begin to show
pressure within 30 seconds in warmer temperatures and
approximately one minute in very cold weather, stop the engine and
find cause before continued operation. 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.
RECOMMENDED STARTER DUTY CYCLE
Operate the starter motor 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, operate the starter motor again, three
cycles of 10 seconds followed by 20 seconds of cool down. If the
engine still does not start, try to find the cause.
(Continud Next Page)
14-26 U.S. 172SPHAUS-03