THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
Effective: 01/01/2008
4-11
C. While the pre-oiling is in progress,
turn the propeller shaft in the normal
direction of rotation to prevent the
accumulation of oil in the lower
cylinders and to aid in the distribution
of the oil to the bearings.
D. At completion, install the drain plug
and washer in the sump, and
lockwire the plug.
E. Service oil tank.
PRE-OILING (OPTIONAL)
A. Remove front spark plugs, one top
cylinder rocker box cover, and main
oil sump plug.
B. Turn engine with starter until flowing
oil appears at top rocker assembly
and a minimum of one gallon of oil
drains from the sump.
*NOTE*
Do not use starter for more
than 3 minutes at a time
without allowing sufficient
cooling period to prevent
overheating of starter.
C. Replace sump plug, rocker box
gasket and cover, front spark plugs,
and service oil tank.
D. Upon initial start, do not exceed
1000 RPM until engine oil
temperature reaches 40ºC (104ºF),
and do not exceed 1800 RPM until
oil temperature reaches 60ºC
(140ºF), and the oil pressure is within
normal operating range.
CARBURETOR
The Stromberg Model NA-Y9E1
carburetor is a two-barrel, two-float
updraft type carburetor (see Figure 4-4).
The carburetor meters fuel in proportion
to the mass air flow to the engine. The
mass air flow to the engine is determined
by the throttle opening. After being
metered by the carburetor, the fuel is
discharged into the air-stream to the
impeller where it is thoroughly mixed with
the air, vaporized, and then delivered to
the cylinders through the intake pipes
and inlet valves.
CARBURETOR REMOVAL
Carburetor removal may be
accomplished as follows:
A. Remove access panels.
B. Disconnect throttle and mixture
control linkage.
C. Disconnect and cap all fuel lines at
carburetor.
D. Remove nuts holding carburetor to
adapter duct assembly. Loosen air
mixing chamber flexible hose and
braces as required to allow for
carburetor removal.
E. Remove nuts holding carburetor to
engine, remove carburetor and
install cover on mounting pad.
CARBURETOR INSTALLATION
The NA-Y9E1 carburetor is mounted on
the engine so that the float chambers are
located front and rear with the fuel inlet to
the rear. The fuel inlet, a 1/2 pipe tap, is
located at the top of the fuel strainer
boss. The fuel pressure gage
connection, a 1/8 pipe tap, is provided on
the side of the strainer boss. To install
the carburetor proceed as follows:
A. Remove cover from mounting pad.
Install carburetor (no gasket) on
mounting studs and torque as
required (see Table 2-3, Section 2).
B. Install adapter duct assembly to
carburetor. Tighten mixing chamber
flex hose and braces that were
loosened or removed during
carburetor removal.
C. Uncap
and
install all fuel lines.
D. Connect throttle and mixture control
linkage.
*NOTE*
The throttle lever has a 70
degree radial travel and
requires a control rod
movement of 1-25/32 inches.
