Piper Comanche PA-24 Service Manual page 591

PIPER COMANCHE SERVICE MANUAL
FIGURE 7e·7. FUEL INJECTOR
I. lOLl t~I[D ADJUIT"'IM'!"
Z. 101.' w ...
,.V.,
AONIT ... 'IIT
J.
JoIIJ:TUII' UIIW
6. 'ulL 1I"II11N
d. Wben the idliDJ 'Peed has been suhilized. mow the coapit mixture conuol with a smooth. steady
pull toward the "Idle Cut-off" position and observe the tachomour for aoy change during the "Ieanlllg"
process. C.lunan must be exercised
to retum
the mixture canuel
to
the "Full RIch" position before the
RPM can drop to a point wb .... the eDgIlIe cuts out. An inc:reue of more thao '0 RPM while "leaning ou,"
indicates
III
excessively rich idle mixture. An immediate decnue
III
RPM
(if
not preceded by a momentuy
increase) indicates the idle mlXtUrc is
tOO
lean.
c. If the above LDdica.res thar: the idle adjusanent is tOO rich or roo lean. tum the idle mixture
adjusancnt in the direction rcqulJ'ed for correction. and check mis
n~w
position by repel-ring the above
procedure. ,\Wee additional adjustments as necessary Each time the &djusancnt is changed. the engine
should be run up to ZOOO RPM to clear the ellJll'e before proceeding with the RPM check. Make final
adjustment of the idle 'Peed adjustment to obwn the desired idliDJ RPM with closed throttle. The above
method aims
at
a setting that
will
obtain maximum RPM with minimum manifold pressure. In case the
sertina:
does not rema.u1 stable, check the idle Linkage; any looseness in this linkage would cause erratic
idling. In all cues. allowance should be made for the effect of weather conditions and field altitude upon
idling adjustment.
2
H9
POWER PLANT
ISSUED: S/1Sn2