Evolution Engines 26GX - Manual (Page 4)

3
mounting the engine
Most model airplane designs make provision for an engine
mount. It is extremely important that the engine mount be
securely attached to the airplane’s firewall and that the engine
is securely fastened to the engine mount. Follow the instructions
included with the airplane for mounting the engine.
The engine should be fastened in place with 4 screws through
a conventional beam mount. Use 8x32 screws for the 26GX. If
you decided to fasten the engine using a flexible motor mount,
always choose parts with enough integrity and strength. Make
sure all screws are tightened and regularly check that they are
tight and in good condition.
Important: Air is necessary to cool the engine during operation.
Make sure that sufficient air circulation through the cowling is
provided. As a basic reference, the outlet area should be 3–5 times
the area of the inlet area to provide adequate cooling.
Throttle Linkage
Carefully attach the throttle linkage to the engine using a ball
link on the carburetor. Make sure that 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 butterfly
to the low idle position. Adjust the length of the pushrod until full
throttle opens the carburetor butterfly fully, while low throttle, low
trim completely closes the butterfly.
Attaching the Fuel Lines
Use medium gasoline-compatible fuel line in the fuel tank as
well as the supply line to the engine.
Selecting a Suitable Propeller
The Evolution 26GX has been designed to generate maximum
power at 8500 rpm, according to the type of exhaust used. If you
wish to utilize the maximum power output, choose a propeller,
which will allow the engine to reach these revolutions, or slightly
lower revolutions. (The engine will unload in the air depending on
the aircraft speed and propeller selected.) We do not recommend
using propellers that allow the engine to reach more than 9000
rpm on the ground.
Fuel for the evolution gas engine
The Evolution gas engine has been designed to run on a mixture
of high-quality unleaded gasoline and synthetic oil intended for
racing 2-stroke gasoline engines. For the break-in period of the
new engine, mix the fuel in a ratio of 30 parts gasoline to 1 part
lubricant. After break in, use a ratio of 40 parts gasoline to 1
part lubricant.
Suggested Propeller Dimensions
16x8 16x10 16x11 16x12
17x8 17x10 17x12
18x6 18x8
26gX
evolution 26gX Ignition System
The 26GX uses an ignition system that can have the "battery test"
function disabled or enabled. The engine comes with the ignition system
battery test disabled. You can activate the ignition system "battery
test" function by inserting the small red jumper provided in the ignition
package. PLEASE READ THE INSTRUCTIONS ON ENABLING THE BATTERY
TEST FUNCTION IF YOU WISH TO DO SO WITH YOUR IGNITION SYSTEM.
Refer to page 8.
We recommend the use of a system power switch, or "kill switch," so
that the ignition can safely be turned on and off. When you prepare to
install the ignition in the aircraft, please check to make sure the ignition
system battery test is "DISABLED" (the red jumper is not installed in the
ignition).
cAuTIon: IF you enAbLe THe bATTeRy TeST FuncTIon, PLeASe ReAD THe
FoLLoWIng FoR youR oWn PRoTecTIon:
During the battery test, a series of flashes are generated and voltage is
measured. This will cause a spark plug to be fired for up to 2 seconds
to check the condition of the battery prior to starting the engine. If
the engine is in the compressed position (i.e., the piston is above the
exhaust port in either the up or down part of the stroke), any compressed
fumes may ignite, causing the propeller to turn, and possibly the engine
to start, unintentionally.
To prevent this with the Evolution Gasoline GX Ignition System, check
to be sure the ignition system is turned off and that the piston is in the
bottom dead center (BDC) position. Bottom Dead Center can be found
by rotating the propeller through the compression stroke. As you rotate
the propeller you will feel it tighten, then suddenly loosen. Once the turn
becomes very easy, you have completed the compression stroke and are
at BDC. Once you are sure the piston is in this position, you may turn on
the ignition power switch and operate the system safely.
As always, it is important to use extreme care when near or with
engines, fuel and propellers. Please use caution when working with
these components. If you have any questions or concerns, please contact
our Product Support team at 1-877-504-0233 or productsupport@
horizonhobby.com.
12912_EVO(26GXmanual).indd 3 3/3/08 12:00:52 PM