Cessna SKYHAWK 1976 Pilot Operating Handbook page 49

CESSNA SECTION 4
MODEL
172M NORMAL PROCEDURES
AMPLIFIED PROCEDURES
STARTING ENGINE
During
e~ine
starting, open the throttle approximately
1/8
inch. In
warm temperatures, one or two strokes of the primer should be sufficient.
In cold weather, up to six strokes of the primer may be necessary. If the
engine is warm, no priming will be required. In extremely cold temper­
atures, it may be necessary to continue priming while cranking the engine.
Weak intermittent firing followed by puffs of black smoke from the
exhaust stack indicate overpriming or flooding. Excess fuel can be
cleared from the combustion chambers by the following procedure: Set
the mixture control full lean and the throttle full open; then crank the en ­
gine through several revolutions with the starter. Repeat the starting
procedure without any additional priming.
If the engine is underprimed (most likely in cold weather with a cold
engine) it will not fire at all, and additional priming will be necessary.
As soon as the cylinders begin to fire, open the throttle slightly to keep it
running.
After starting, if the oil gage does not begin to show pressure within
30 seconds in the summertime and about twice that long in very cold
weather, stop engine and investigate. Lack of oil pressure can cause
serious engine damage. After starting, avoid the use of carburetor heat
unless icing conditions prevail
NOTE
Additional details concerning cold weather starting and
operation may be found under COLD WEATHER OPERA­
TION paragraphs in this section.
TAXIING
When taxiing, it is important that speed and use of brakes be held to
a minimum and that all controls be utilized (see Taxiing Diagram, figure
4-2) to maintain directional control and balance.
The carburetor heat control knob should be pushed full in during all
ground operations unless heat is absolutely necessary. When the knob is
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