Piper Comanche PA-24 Service Manual page 566

PIPER COMANCHE SERVICE MANUAL
Th. oil pressure rut . . . Iem ...... located on die accessory housin •• is provided as a means to rut .. any _
solid particles that may have pused through die Netion screen in the sump. Af ... beina filtered through
. .
the pressure rut ... the oil is fed througb a drilled passqe.o the oil preawe relief valv •• located in die upper
right side of th .• c:nnkcue forward of the aeceaory housin •.
This relief valve regulates the ...... e oil pressure by aIIo"",,,
excess
oil to retIIm
to
the Rlmp. while die
balanc. of the presNre oil is fed to die main oil pIlery in the righ. half of the c:nnkcase. Residual oil is
retIImed by sraviry to the Nmp where. af ... passing through die Netion
scr ......
i. is again circulated
through the .".me.
The turboch ..... s
are
lubricated
I!Y
!npne oil which is Rlpplied
'0
the turbo oil pIlery by lines
connected to die ""line accessory housi",. IncOTJlOrated in tbe oil Npply line is • pressure regulator poppet
valve. The ... of a resuicted fitting
reduces
.".m. oil pressure
to
30-35 psi prOSltlre required ior th.
rurt>ochargetS. Oil is scav .... ed from die turbocharg .. sump and returned to the ... ine sump by a scavencer
pump installed on the hydraulic pump drive pad of th."""e acCOSlOry housing.
7C·3. TroublabootiDa. Troubles peculiar to the pow .. plant
arc
listed in Table VllC·ll in die back of thi>
section. along with their probable causes and suaested remedies. When rroubleshou""I .ngines. ground the
magn.to primary circuit before performins any checks on the ipUtion system.
7C .... Engine CowliDg.
7C·l. Removal Of Engine Cowling.
a. Ascerwn that die
master
switch and "'""'etO swi.ches
arc
in die off position.
b Release the three cowl fasteners on each side of the engine comparancnt.
c. Remove atw:hing screws from die tOP cowl
at
die ruewall. _
d. Remove attaching screws from the nose section parting sunaces. . .
c. Remove tile
tWO
amcning
nuts. washers and screws 5ecuring the top cowl channels to firewall.
f. Lift the tOP cowl from dI •• ngin. assembly.
g. DlSCor.ncct nose gear door acmati", rods.
h.
Dj~onncct
cowl flap (onttOi cables.
I.
DISconnect gear door frame ch&nncls from firewall Uld a.cuchmcnt SU:lpS from tubular structure
by removing screws.
J.
DiSConnect drain lines from bottom cowl.
k.
Remove bottom cowl by removing screws securing it to tbe firewall.
7C-O. Cleaninl. Inlp.ction And Repair Of Engin. Cowlinl.
1.
Crean cowling
With
a. suitable cleaning solvent and wipe dry
With
a. clean doth.
b. Inspect cowling for dents. cracks. loose rivets. eiongaccd holes and damaged or missing futcncn
c. RepaIr all deiects to prevent funhcr damage. Fiberglass repair procedute'S may be a.ccomplished
according to Fibcrgla.ss Repair!. SectIon IV.
2
Gl0
POWER PLANT
ISSUED: 8/18172