Thrush Aircraft S2R-R1340, Руководство по обслуживанию

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THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
Effective: 01/01/2008
4-3
POWER PLANT GENERAL
Ref. Figure 4-1
The engine has nine cylinders, the
cylinders being disposed radially on an
aluminum crankcase section.
Magnesium alloy is used for the
crankcase front section and the super
charger section. The cylinders are of
steel and aluminum construction. The
barrels are machined from steel forgings
and have integral cooling fins. The
heads are made from aluminum castings
and have deep cooling fins and rocker
boxes cast integrally. The head is
screwed and shrunk onto the cylinder
barrel, forming a semi-permanent
assembly. Ignition is furnished by two
high-tension magnetos mounted on the
rear case assembly. The right magneto
fires the front spark plugs and the left
magneto fires the rear spark plugs, and
both plugs are fired simultaneously. Fuel
and air induction is through a float type
carburetor, a centrifugal supercharger,
and intake pipes. The propeller is driven
directly from the engine.
The following standard terms are used
throughout this section:
Front ......................................... Propeller End
Rear................................... Anti-propeller End
Right and Left ......................As viewed facing
rear of engine
Crankshaft, Propeller.................Clockwise as
Shaft or Propeller viewed facing
Rotation rear of engine
IGNITION SYSTEM
Ignition is furnished by two high-tension
magnetos mounted on the rear housing
(see Figure 4-2). The purpose of the
magnetos is to supply sufficient voltage
at the proper time relative to crankshaft
travel so that an equal distribution of
voltage will be delivered to the spark
plugs through the ignition cable
assembly. Rubber protectors are
installed on all spark plug leads to protect
the cables from moisture, oil, grease and
engine heat.
MAGNETO REMOVAL
Ref. Figures 4-1 & 4-2
Magneto removal may be accomplished
as follows:
A.
Loosen the knurled coupling that secures
the flexible manifold conduit to the
distributor block cover elbow. Remove
the two screws that secure the elbow to
the distributor block cover.
B.
Remove the screw that secures the
distributor block cover halves of the
magneto.
C.
Remove the safety pin; disengage the
two spring locks on the distributor block
cover. Remove the cover halves. Lift
out the distributor blocks and wrap each
block in oiled paper.
D.
Remove the three bolts that secure the
magneto to its mounting pad and lift off
the magneto and rubber coupling.
MAGNETO TIMING AND
INSTALLATION
Before installing a magneto on the
engine, the internal timing of the
magneto should be checked.
E.
Remove the breaker compartment cover.
F.
Attach the red wire of PWA-2417 (or
equivalent) indicator to the breaker points
and ground the black wire to the
magneto housing.
G.
Place a straightedge against the step on
the breaker cam and turn the magneto
drive shaft in the normal direction of
rotation. The light of the indicator should
flash on just as the straightedge comes
into alignment with the timing marks on
the magneto housing. The timing marks
seen through the timing window should
be aligned at this point.
TIMING AND SYNCHRONIZING
MAGNETOS
To determine whether the magnetos are
properly timed to the engine and
synchronized with each other, perform
the following: