Piper Comanche PA-24 Service Manual page 602

PIPER COMANCHE SERVICE MANUAL
7C-61. Imp .. IioD AIId
CIaaiat
Of Sperl<
PIuc.
L
Vilually iDIpect each
opuIr.
pi", for the followiaJ nolHepairablc
dcfcc:a,
I. Severely cI&mqed IbclJ
or
lbicld thracIa aidted up. stripped or =athraded.
Z. \IIdIy butaed
or
",1IDde:I1hclI
haIIoas.
3.
Out~f
.... uad or
damoaed
shiddifts banel.
4. Chipped. cracked, or brokCII ceramic
illlulator portioal.
5. \IIdIy ctOCIed e1ecaoda wom
to
approximately 511' ! 1o of ofiliDai size.
b. C\caa the sparl< pi",
as
required.
removiDI
carbon and foreiln dcpotia.
c. Test the sparl< pi", both c!'oCIricaily and for resirwlcc.
cI. Set the decaocle pp II .016
:I:
.1 of an inch
or
if alllloothcr operation at idle speed &ad raiueed
IIIIfIIctO
cIro~ff
is
desire.
set
at .018 to .02Z of an inch. However. with wide pp Jetting the plup
must be
scrrieed at
more
frequmt intcrYala. Fine wire plarinutn or iridium elecaoclcs Ibould be
set
at .015 to .018
of an inch only.
7C-6Z. 'nm ll,rio .. Of Spork
ftup.
8cfoft iastalIing sparl< pi ..... UCCttaiI! . U the thrads within the
cylindct arc clean and not damaaed.
L
Apply ... ti1Cizc compound sparingly on the duada ... d iDst&ll plkct ... d ,pari< pi ..... Torque 360
to 4Z0 incb pounds.
CAUTION
Mai<e certain the deep socket is p",pcrly teated on the sparl< plug
hexqon
as
damqe to the plug could result if the wrencb is cocked to
one S1dc wben pressure is applied.
b. Carefully insert the terminal insulator in the sparl< plug and tighten the coupling nut.
7C-63. Lubricalion System.
7C~.
Oil Praourc Relief VIiw. Tbe adjusablc
)i1
pressure relief valvo enables the operator to mainuin
engine oil p .... ure within the specified limia (refer to the encino manufacturer', appropna .. m ... ual). The
valve i. located above ... d to the rear of No, , cylinder. If the pr ....... under normal operating condition,
should consistendy exceed 90 psi. oc run I ... than 60 psi. adjust the valve as foUows,
With the encine thoroughly warmed up and runnlllg
at
a maximum of ZZOO RP!.I. observe the readi",
on the oil pressure puge, If the pre .... re is above 90 psi. stOp engme. back off the adjusting screw one or
two full rums. If pressure is tOO low,
tum
adjumng screw further intO the relief valve plug. therebv
incre:asm, the tension on the relief valve spri.nc. When the valve has been satIsfactorily ad.ju.sted. lockwlre
the Clown nut to the drilled car projecting from the valve mountinJ boss. The engine has a thermos .. nc
bypass valve as a safety feature. The val"" will open ,hould the tempctature exceed a sate operating level
and allow the oil to circulate in the system to aVOId permanent damage to the engine.
POWER PLANT
ISSUED: 8118n2
2
H20