Piper Comanche PA-24 Service Manual page 495

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PIPER COMANCHE SERVICE MANUAL
FIGl:RE 7 A-I3. FUEL AIR BLEED NOZZLE
d' When the idling speed has been stabilized. mo\e the cockpit mixture control with a smooth.
stead~
pull toward the "Idle Cut-Off" position and obserYe the tachometer for any change during the "leaning"
process. Caution must be exercised to return the mixture control to the "Full Rich" position before the
RPM can drop to a point where the engine cuts out An increase of more than 50 RPM while "leaning out"
indicates an
excessivel~
rich idle mixture. An immediate decrease in RPM (if not preceded by a momentan
increase) indicates the idle mixture is too lean
e If the abo\e indicates that the idle adjustment is too rich or too lean. turn the idle mixture
adjustment in the direction required for correction. and check this new position by repeating the abo,"
procedure Make additional adjustments as necessary Each time the adjustment is changed. the engine
should be run up
to
2000 RPM to clear the engine before proceeding with the RPM check Make final
adjustment of the idle speed adjustment to obtain the desired idling R PM with closed throttle The abo\C
method aims at a setting that will obtain maximum RPM with minimum mamfold pressure In case the
setting does not remain stable. check the idle linkage: any looseness in this linkage would cause erratic
idling In all cases. allowance should be made for the effect of weather conditions and field altitude upon
idling adjustment
7
A-o~.
Fuel Air Bleed Nozzles.
7A-64 Removal Of Fuel Air Bleed Nozzles. The noules must be carefully remO\cd as the\ or the
c\ Iinders may be damaged
a
Lift the side acces- panel of the engine cowling
b Disconnect the fuel line from the nonle
c Carefully remo\C the nonle using the correct size deep socket
d. Clean and inspect the nozzle as given in paragraph 7 A-65.
ISSl:ED: 8/18/72
2D17
POWER PLA"T