Dusty Contitions; Seacoast And Humid Areas; Ground Service Receptacle; Hand Cranking - Cessna 177 SERIES Service Manual

11-86. DUSTY CONDITIONS. Dust induced into the
CAUTION
intake system of the engine is probably the greatest
-------- ONsingle cause of early engine wear.
When operating
Due to the desludging effect of the diluted under high dust conditions, service the induction air
oil, engine operation should be observed filter daily as outlined in Section 2. Also, change
closely during the initial warm-up of the engine oil and lubricate the airframe more often than
engine. Engines that have considerable specified.
amount of operational hours accumulated
since their last dilution period may be 11-87. SEACOAST AND HUMID AREAS.
In salt
seriously affected by the dilution process. water areas, special care should be taken to keep
This will be caused by the diluted oil dis- the engine and accessories clean to prevent oxida-
lodging sludge and carbon deposits within
tion. In humid areas, fuel and oil should be checked
the engine. This residue will collect in frequently and drained of condensed moisture.
the oil sump and possible clog the screened
inlet to the oil pump.
Small deposits may 11-88. GROUND SERVICE RECEPTACLE. With the
actually enter the oil pump and be trapped
ground service receptacle installed, the use of an ex-
by the main oil filter screen. Partial or ternal power source is recommended for cold weather
complete loss of engine lubrication may starting and lengthy maintenance of the aircraft elec-
result from either condition. If these con- trical system with the exception of electronic equip-
ditions are anticipated after oil dilution, ment.
the engine should be run for several min-
utes at normal operating temperatures and
CAUTION
then stopped and inspected for evidence of
sludge and carbon deposits in the oil sump Before applying external power to the ground
and oil filter screen. Future occurrence service plug, insure AVIONICS POWER switch
of this condition can be prevented by dilu- is in the OFF position, preventing transient
ting the oil prior to each oil change. This voltages from damaging the semiconductor
will prevent the accumulation of the sludge circuitry in the electronics installation.
and carbon deposits.
NOTE
11-85. HOT WEATHER. Engine starting in hot
weather or with a hot engine is sometimes hampered
Electrical power is supplied through a split
by vapor formation at certain points in the fuel sys-bus bar, one side containing electronic sys-
tem. To purge the vapor, remove the carburetor terncircuits and the other side having gen-
vent plug and purge the carburetor and lines by turn-
eral electrical system circuits. In the split
ing the fuel shut-off valve on. Purge the carburetor bus system, both sides of the bus are on at
in this manner until fuel stands level with the vent her an external
plug opening. Replace the carburetor vent plug and
power source is connected or the starter
operate the engine to make sure that the condition
swi is tred o the oe contactor
has been corrected. switch is turned on; then a power contactor
w~h~~as been
corrected
~.
is automatically activated to open the circuit
to the electronic bus. Isolating the electronic
Engine mis- starts characterized by weak intermittent circuits in ts a r r s h l tran-
explosions followed by puffs of black smoke from the ciruts ts manner eents ham u tan-
exhaust are caused by over-priming or flooding. This sient voltages from damaging the semiconduc-
situation is more apt to develop in hot weather, ortors the elect equipment.
when the engine is hot. If it occurs, repeat the start-
ing procedure with the throttle approximately one-half e r ce pl receptale crt inoro
OPEN and the mixcture control in IDLE CUT-OFF rates a polarity reversal protection. Power from
AsPeng ,move mixature control n E to fFll the external power source will flow only if the ground
As the engine fireas, move throture contti to de d service plug is correctly connected to the aircraft.
RICH and decrease the throttle setting to desired
RICH and decrease the throttle setting to desired If the plug is accidentally connected backwards, no
~~~~~idling
speed~~.
~power
will flow to the aircraft electrical system,
thereby preventing any damage to electrical equip-
Engine mis-starts characterized by sufficient power thereby preventing any damage to electrical equip-
ment.
to disengage the starter but dying after three to five
men
revolutions are the result of an excessively lean mix-
ture after the start. This can occur in either warm The battery and external power circuits have been de-
or cold temperatures. Repeat the starting procedure signed to completely eliminate the need to "jumper"
orwith additional primingtures. Repeatthestartingpracross the battery contactors to close it. A special
fused circuit in the external power system supplies
the needed "jumper" across the contacts so that with
CAUTIONI
a "dead" battery and an external power source ap-
plied, turning the master switch ON will close the
Never operate the starting motor more than
12 seconds at a time. Allow starter motorbattery
contactor.
to cool between cranking periods to avoid
11-89 HAND CRANKING. A normal hand cranking
overheating. Longer cranking periods will
procedure may be used to start the engine, if the
shorten the life of the starter motor.
starter is not engaged with the ring gear.
11-32starter Cha not engaged with the rng gear.
11-32 Change 7