• If the propeller hits somethingwhile
the engine is in operation, immediately
stop the engine and check for damage.
• Start the engine on a flat surface free
of stones or other debris.
• When mixing fuel, or operating the
engine, do so in a well-ventilated
area.
Engine Mounting and
Muffler Attachment
Notes
Mount the engine on aircraft grade
plywood with more than 10mm of
thickness or to a mount of equivalent
strength, and firmly fixed, with 4 bolts.
We highly recommend the use of the
Saito motor mount (SAI3695) to mount
this engine to a model aircraft.
Note:
Be sure to use flat washers or a
metal plate on the reverse side of the
mount to prevent the bolts from
sinking into the plywood. Before
flying the airplane, be sure to check
for loose bolts.
Note:
Since this engine is equipped
with a floatless carburetor with a
diaphragm pump, the direction of the
cylinder and the position of the fuel
tank can be upright or inverted.
When you attach the muffler, use a
drop of oil on the threads to ease the
assembly. Screw the exhaust manifold
into the engine exhaust port and the
muffler as far as the thread will allow
(see above drawing). Notice the use
of the two wrenches used in tightening
the two nuts on the muffler/manifold
connection. Use of Locktite is
recommended.
Remember to ensure cooling air passes
by the engine and muffler in a cowled
environment.
Figure 1
T h R O T T l E l I N k A g E A N D P R O P E l l E R
3
2
E N g I N E M O U N T I N g A N D M U F F l E R A T T A C h M E N T
Throttle Linkage
Carefully attach the throttle linkage
to the engine using the included ball
link on the carburetor throttle arm.
Make sure the linkage is free to operate
from low throttle to high throttle and
confirm that the low throttle setting on
the transmitter closes the carburetor
throttle barrel to the low idle position.
Adjust the length of the pushrod until
full throttle opens the carburetor
throttle barrel to the fully open
position, while low throttle, low trim
completely closes the throttle barrel.
Propeller
Recommended Propeller Sizes:
The recommended propeller sizes
are shown in the table below. The use
of a carbon fiber propeller is highly
recommended. Remember that the use
of a large propeller will require care
in balancing it. Vibration will reduce
performance and can result in damage
to the engine and airframe.
Benchmark propeller used was an APC
18x6W propeller @ 8,300 rpm.
For break in, Saito recommends the
use of an 18x8 or 19x8 carbon fiber
propeller for initial break-in and
approximately 20 subsequent flights.
The engine produces the maximum
output when the engine is running
at about 8,300 rpm. We would
recommend using a propeller which
makes the engine run at approximately
7,000 – 9,000 rpm while the airplane
in flight.
Propeller and Fuel
Consumption
In order to decrease fuel consumption
and prolong the life of the engine,
a propeller should be selected that
maximizes rpm's when the throttle is
fully open, and an airframe that will
perform flights at about 90% of the
propeller output. If the load is large,
(the diameter & pitch of the propeller is
large) the air-fuel mixture will have to
be rich. If the load is small, the rpm’s
will be high, but the fuel consumption
is lowered because the high-speed
needle valve is closed or leaned out
more.
Diameter x Pitch (inches)
17x 10-13"
18x 8-10"
19 x 8-10"
20 x 8"
