Protection Of Engine Mount; Engine Shock Mounts; Turbocharger Nomenclature - Piper PA-24 Comanche Service Manual

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PIPER COM ASCHE SERVICE MASt" At
abo Time magnetos to engine. (Refer to paragraph
7C-5~.)
ac. Install cowling. (Refer to paragraph 7(-7.)
ad, Connect battery ground cable. turn fuel selector valve on. open throttle full and turn on the aux iliarv
fuel pump, (heck for fuel leaks.
7C-~Oa,
Protection
or
Engine Mounl. The lower engine mount tubes which are next to the turbochargers have been
painted with a special heat resistant paint. Should the mount need repainting. the following procedure must be followed
to insure the heat resistant quality:
a,
Strip all old paint from the lower engine mount tubes.
h. Sand the full length of the tubes and
remove
all grease and oil.
C.
Aprly three brush coats of extra high H-170 Heat Rem. paint. or Krylon high heat aluminum paint
\0,
I~Ol.
or Randolph products heat resistant coating \0. Kn60 or
~7tJl.
\OTE
The engine mount tubes should be warm during the paint application.
but not hot.
d. -\110\\ twelve
hours between brush coats.
~C·:!1. Engine Shock :\"Iounls. Replace engine shock mounts. Refer to Figure 7C·~
for the proper arrangement 01
engine shock mount assemblies. Place shock mount with P \ J-.:\049-.:\5 in the top front position and shock mount \\ ith
P \
,1·~(W}·.1~
in the bottom front position. Place shock mount with P \ J-.:\049-.:\4 in the top rear position and ... hock
mount with P \ J-.:\O-l9-J5 in the bottom rear position. Torque shock mount bolts to -l50 to 500 in. Ibs. with
torque
wrench applied to bolt heads and safety.
-:'(-22. Turbocharger.
~C-2:!A,
Turbocharger Somendalure. Many unfamiliar terms may appear on the following pages of this manual. An
understanding
1)1'
these will be helpful. if not necessary. in performing maintenance and troubleshooting. The following
is a
list
1)1'
commonly
used terms and names as applied
to
turbocharging
and a brief description.
TFR'1
Supercharge
Supercharger
Turbine
MEA\I\G
To increase the air pressure (density) above or higher than ambient condition...
A device that accomplishes the increase in pressure,
More
commonly referred to as a "Turbocharger" this device is driven by a
turbine
The turbine is spun by energy extracted from the engine exhaust gas,
The portion of a turbocharger that takes in ambient air and compresses it before
discharging it to the engine.
The exhaust driven end of the turbocharger unit.
The wastegate is a butterfly type valve in the exhaust by-pass which. throughout its
travel from open to closed. allows varied amounts of exhaust gas to by-pass the
turbin. controlling its speed. hence the output of the compressor. The "actuator is
operated by a hydraulic piston operated by engine oil and cylinder with the piston
linked to an arm on the butterfly valve shaft.
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Wa-tegate and Actuator
t
Exhau-t B~-Pas.,)
REVISED: ..1/10/81
2G19
POWER Pl.-\'T