Piper PA-24 Comanche Service Manual page 438

PIPER COMANCHE SERVice MANUAL
The oil pressure filter element, located on the accessory housin•• is provided u a means to mtet any
solid particles that may have puscd through the suction screen in the sump. After bema filtered
thro~'fh
the preuure ruter, the oil is fed through a drilled PUSlle to the oil pressure relief Y2lve, lceated in :he upper
right side of th.'! cnnkcase forward of the accessory housing.
This relief valve rqulaus the ftlJine oil pressure by allOwln'
elCcest
oil
to
retum to the sump, while the
baianceof the pressure oil
is
fed to the main oil
pllcry in
the ript half of the c:nnkcue. Residual oil is
returned by
poavity
to the sump where. after pusmC thfOqh the suction screen. it is
acain
circulated
through the engine.
The tIlrbochaqus arc lubricated
tft
!npne oil -hicb is supplied to the turbo oil gallery by lines
connected to the mpne accessory housina.lncorporatcdin the oil supply line
is
a pressure replator popper
valve. The use of
&
restricted fininl reduces CftIine oil prasure to
30-3'
psi pressure required for the
turboc:hUJCtS. Oil is SQvenpd from the aarbocballer sump and rerumcd to the crcine sump by a scavenlft'
pump inna1lcd on the hydraulic pump drive pad of the mpc accasory housing.
7e·].
TroublesbooM,. Troubles peculiar to the power plant
ate
listed
in Table
vnc·n
in the back of this
section. along with their probable causes and SUgeHed remedies. When troublcshoutiq enpnes. groun4 rhe
magneto primary circuit before pcrfotJllint any checks on the iJnition system.
7C..... Enpac CowliDs.
iC·S. Removal Of Enpae CowtiDl.
a. AscerWtl that the master switch and
mapetO switches arc in the off position.
b. Release the three cowl fasteners on each side of the mpe compartment.
c. Remove attachinl5CtCWS from the top cowl at the ftrewall.
d. Remove attaching
screws
&om the nose section partiftl surfaces.
e. Remove tne tWO attachin. nuu. wuben and
screws
securing the tOP cowl channels to firewall.
f. Lift the top cowl from the enpne UlCmbly.
g. Disconnect nose
gear
door accuatina rods.
h.
D;~onnect
cowl nap control cables.
i.
Disconnect leat 400r frame channels from firewall an4 attachment str:LpS from tubular structUre
by removing screws.
J. DIsconnect min lines from boltom cowl.
k. Remove bottom cowl by removing screws securing it to the firew1ll.
~C-6.
Cleaning, Inspection And Repair Of
Eope
Cowlinl'
a. Cle:Ln cowling with a suitable cleaning solvent an4 wipe dry with a dun cloth.
b. Inspect cowling for denes, cracks. loose rivets. elongated holes 1Il4 dunqe4 or missinlJ futeners.
c. Repair all defects to prevent further damqe. Fibertlass repair procedures may be lccomplished
acc:ording to Fiberglass Repairs. Section IV.
POWER PLANT
ISSUED: 8/18/72
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