Piper PA-24 Comanche Service Manual page 437

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PIPER COMANCHE SERVICE MANUAL
SECTION
vue
POWEll Pr...ANT
PA·24-260 (TUJUIOCHARGED)
7C·1. Incroduetioa. This section coven power plants IlJed in the PA·24-260 Turbo Comanche and is
comprised of instructions for the removal. minor
~pair.
service and insullation of the engine cowling.
propeller. propeller governor. en,me. eftlJine shock mounts. induction system. fuel injector. t\\rbocharJef.
Nel
air
bleed nonles. iJnition synem and lubrication system.
7C·2. Description. The PA·24-260 Turbo Comanche is powered by an Avco-LycominJ lO·HO·R1AS. six
cylinder. direct drive.
Wet
sump. horizontal opposed. fuel injected.
air
cooled cnfine with a compression
ratio of 8.5:1. rated a 260 HP at 2700 RPM. and desiJned to operate on
100/130
(minimum) octane
aviation J1'&de fuel. The cnpe contains components which make it suitable for curbochUling.
CowlinJ compLetely encloses the engine and consists of cwo biftlCd side access panels. an upper and
lower sectIon and a nose section. The cowl flaps are an intqraJ pan: of the lower cowl and are operated
manually throulh mechanicallinkap.
Tbe propeller is a Hartzell conS'taDt speed. conaoUed by a governor mounted on the engine supplying
oil through the propeUer shaft at various pressures. Oil pressure from the JOvcrnor moves the blades intO
high pitch (Low RPM). The centrifugal twistiJll moment of the blades move them into low pitch (High
RP~).
The airplane's induction system consists of a dry
type air
flltcr and alternate air door. The e:'lgine fuel
system consists of a Bendix RSA-5A01 type fuel injCC'tor and a Lear-Seigler fud supply pump as an integral
put of the fuel injCC'tor
symm.
Two Rajay part number RJOOSOoI02 turbochlllft'S arc attached to the
engine.
~ual
waste pte concrol of the turbochltJCf provides the pilot with complete freedom of choice
in turbochUJcr use. A pum-puUconcrol is installed for
WIStC
pte contrOl.
Bendix·Scintilla S6LN·1Zoo series
maenctOS
arc installed on the eftline. The system consists of two
mqnetos with "shower of sparks" retard points in the left mllftcto. necessary for starting.
In addition to the aforementioned components. the encine is eqUipped with an alternator. a geued
starter and vacuum pump. The enJine mount is steel t\\binl conser Iction attached at the firewaJl and
incorporates Y1bration absorbing mounts. From the exhaust stadts. gues are directed to the t\\rbochargcr
waste gate. through or around the t\\rbine. as required. and overboard at the rear of the CJlIine cowl. engtne
nacelle.
The lubrication system
IS
of the full pressure wet sump type. The oil pump. which is located in the
accessory b0usint. draws oil throu,h a drilled PUSlle leading from the oil sucnon screen located in
t~e
sump. The oil from the pump then enters a drilled Pllllle in the accessory housing. which iceds the oil to a
threaded connection on the rear face of the accessory housing. where a flexible line Leads the oil co the
external oil cooler. Pressure oil from the cooler returns to a second threaded connection on the aceessorv
:,ousmg from which poinr a drilled p~e conducts the oil to the oil pressure filter. In the event that cold
011 or an obstrUction should reseiee the oil flow to the cooler. an oil cooler by-pass valve
1$
provided to pass
the
011
directly from the oil pump to the oil pressure filter.
POWER PLANT
ISSUED: 8/18172
2
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