Horizon Hobby EVOLUTION 116GX User manual

Evolution Engines
116GX
USER GUIDE
© 2005 Manufactured exclusively for Horizon Hobby, Inc.
www.horizonhobby.com 800-535-5551
8084

Introduction
Congratulations on your purchase of the newest and one of the most technically advanced 2-stroke gas model airplane engines in
the world. Whether you are new to the sport of model aviation or an experienced flyer, you will enjoy the features of the new Evolution®
GX engine. Evolution engines are designed to be the most powerful in their class, extremely easy to start and operate, and provide years of
enjoyable service. These engines incorporate many unique features designed to ensure success with your new engine. This user’s guide is
intended to provide the basic information required to operate and maintain your Evolution GX engine.
Important: While the Evolution engine is extremely easy to operate, if this is your first experience flying a model airplane, it is highly
recommended that you have the help of an experienced modeler during the first few flights. Your local hobby shop or flying club can put
you in touch with an experienced pilot in your area.
Before using this engine, please read these instructions carefully. 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 attached to the engine mount. Follow the instructions
included with the airplane for mounting the engine. The engine
should be fastened in place to the firewall with 4 screws. Use
¼” or 6mm screws. If you decide to fasten the engine using a
flexible motor mount, always choose parts with enough solidity and
strength. Make sure all screws are tightened and regularly check
that they remain 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.
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 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 throttle 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® 116GX has been designed to generate maximum
power at 5800–6300 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).
Suggested Propeller Dimensions
Two-blade propellers:
28x10-14, 30x10-12, 32x10
We do not recommend using propellers that allow the engine to
reach more than 7500 rpm on the ground.
Evolution® Engines 2-Year Warranty
This Evolution Engines product is guaranteed to be free from
defects in materials and workmanship for a period of 2 years
from the date of purchase by the original owner. This warranty
is not transferable. Horizon Hobby reserves the right to inspect
any and all equipment involved in a warranty claim. Repair or
replacement decisions are also determined by Horizon Hobby,
Inc. Collateral damage of any type is not covered under this
warranty.
This warranty does not cover any component parts damaged
changed by modification. In no case shall Horizon Hobby
or Evolution Engines liability exceed the original cost of the
engine.
This warranty does not apply to wear from normal use;
damage or defects resulting from misuse, neglect or abuse;
damage caused by customer disassembly, use of substandard
fuel, use of incorrect accessories (spark plug, propeller, etc.);
or damage resulting from a crash or any use of this engine
other than for which it is specifically intended. Any of the
above will automatically void the warranty of the engine.
In that Horizon Hobby has no control over the final installation
and use of this product, the materials used in installation
or the product in which this engine is installed, no liability
shall be assumed nor accepted for any damage resulting in
the use of this product once it is installed. By the act of using
the installed product, the user accepts all resulting liability.
If the buyer is not prepared to accept the liability associated
with the installation and/or use of this product, the buyer is
advised to return the engine immediately in new and unused
condition to the place of purchase.
Should your engine require warranty or non-warranty repair
service, please package it carefully and return it to the
address below, along with a copy of the original invoice or
receipt and a detailed letter explaining the problems. Write
your name, address and daytime phone number clearly on
the letter and return it via FedEx, UPS or insured Parcel Post
(Evolution Engines will not be responsible for product lost en
route).
For repairs not covered under warranty, please specify in your
letter whether you want an estimate of the repair charges prior
to performing the service (which may cause a slight delay).
Payment for non-warranty repairs should be made by credit
card or money order. If you have any questions concerning this
or other Evolution products please contact the Horizon Product
Support Team at 877-504-0233
Evolution/Horizon Service Center
4105 Fieldstone Road, Champaign, IL 61822
1-877-504-0233
[e-mail]
Control Jet System
Your engine is equipped with a unique system enabling improved
acceleration from idle to high speed. This system allows the
mixture to be controlled while the throttle valve is opening. It will
lean the mixture at low rpm and at idle. Conversely the mixture
will become richer as the throttle is opening. This system provides
better acceleration to high speed and maintains a stable idle.
This system was developed for the Evolution 116cc engine. It is
recommended that you do not change the mixture control leverage.
Idle
High Throttle
2 3

4
Starting the Engine
The new Evolution Engine carburetor comes adjusted to a
basic setting. This setting should be maintained during the
initial break-in runs.
Before you first start the engine, make sure that the spark
plug is screwed in and tightened and that the plug socket
is fitted in place and fastened down properly. Fix the ignition
sensor in the proper position above the magnet with the
screws enclosed. Follow the directions in the Ignition System
addendum to mount the ignition module in your model.
Important: Never turn the engine over with the ignition turned
on unless the spark plug is inserted in the plug socket. This
could lead to ignition damage. Carburetor Adjustments
Adjust needle (L) for low rpm range 3/4 turn open
Adjust needle (H) for high rpm 1 turn open
Basic setting: throttle closed
Adjusting Needle L
Adjusting Needle H
Choke
Pressure Inlet
down. Then restart it and check the adjustment. If everything is all right, you can make your first flight. During the first few flights. do
not overload the engine and do not let it run at high revolutions for long periods of time (very important during hot weather). Use up all
the fuel that was mixed with the oil that is included with your engine. From then on, fuel and oil should be mixed in the proportion 40:1
First, start and warm the engine for 30-45 seconds before attempting to adjust the carburetor. In order to confirm that your engine is
properly adjusted you should follow the procedure below.
5
1) When you are ready to start your engine, make sure that the ignition is switched off, the choke valve is closed and the throttle valve is
partly open. Confirm that fuel is filling the fuel line to the carburetor then switch the ignition to the on position. Flip the propeller smartly
until the engine fires. With the choke in the closed position, the engine will fire then quit.
2) Open the choke valve and set the throttle at a slightly high idle position. Be sure to have a helper hold the model securely. Give the
propeller a few quick flips. When the engine starts, allow it to idle for 30-45 seconds in order for it to warm up to operating temperature.
At this point you can proceed to test the carburetor settings before flying your model. See the following section regarding carburetor
adjustment.
3) If the engine does not start, leave the throttle at the high idle position, turn the ignition off, then on and close the choke valve. Start the
engine with throttle at the fast idle position and the choke valve closed. The engine should fire and quit. If it does, repeat step 2 above.
4) At this point, if the engine still will not start, unscrew the spark plugs and check the contacts. Clean any possible excess fuel (i.e. an
indication of engine flooding) and screw them in again. Further starting should only be done with the throttle at idle position and the choke
in the open position. If the plug is dry, then probably not enough fuel has been drawn into the carburetor. If that is the case, check for
proper fuel feed and then return to the instructions given in paragraph 1.
Having started the engine, leave it running for about 5 minutes at a higher idle speed. Then run it for about 20 minutes, while
changing revolutions from idle to 1/2–3/4 of the range and shortly holding each position—gradually prolong the holding periods. After
10 minutes of operation, open the throttle to maximum for a period of about one minute. At this point, stop the engine and let it cool
Starting the Engine Continued
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 run-in period of the new engine, mix the fuel in a ratio of 30 parts gasoline to 1 part lubricant. After
run-in, use a ratio of 40 parts gasoline to 1 part lubricant.
Throttle Arm 1) Move the throttle from idle to 2/3 of the full throttle position quickly (fast acceleration). Then repeat three times – if the engine
accelerates smoothly go to step 3 below. If acceleration is not smooth, go on to step 2.
2) Faulty acceleration and a tendency to quit is usually attributable to a poor fuel mixture in the medium rpm range. Stop the engine
and recheck the fuel feed (the fuel line must not be pinched or broken). Restart the engine and test acceleration again. If the problem
persists, adjust the carburetor. Open the low speed needle by 1/8 turn and retest. If acceleration is smooth, open the needle by another
1/8 turn—this should be done because the needle was previously set too lean; if atmospheric conditions have changed recently you
may have to readjust the needle. If the engine continues to not accelerate properly, open the low speed needle by 10 minutes. If the
engine’s operation does not improve, shut it off and check the basic setting, restart the engine and test the acceleration. If the engine
runs correctly, go to step 3. If it continues to not accelerate properly, open the low speed needle by another 10 minutes. If acceleration is
faulty, the defect is likely to lie somewhere other than an incorrect adjustment.
3) If the engine accelerates correctly, according to the above test, set it at idle speed and accelerate to full speed. Repeat twice more. If
the engine functions correctly, go to step 4. If it cuts out, open the low speed needle by another 1/8 turn more.
4) If the engine reacts correctly set it at full speed. If revolutions do not drop, the engine has been adjusted successfully. If revolutions
seem to drop, open the high-speed needle by approx. 5–10 minutes.
Caution! The engine must be stopped while you adjust the carburetor in order to prevent injury by the propeller.
Carburetor Adjustment

6
116GX Evolution Engine Dimensions
116GX Evolution Engine Specifications
Bore
Stroke
Displacement
Weight without ignition*
Weight of ignition unit
rpm range
42mm
42mm
116cc / 7.1 cu in
3100 g / 6.8 lb
270 g / .6 oz
1000–7500 rpm
Maximum power output**
Maximum torque**
Fuel
Lubrication
14 hp / 6400 rpm
15N/m / 6100 rpm
Unleaded high-octane gas
Oil w/gasoline
in mixture 1:40
* The value in the table above stands for the weight of a completely assembled engine, including the spark plug, carburetor,
drive washer and prop screws.
** Power output varies with the exhaust used. The value given in the table stands for the maximum available power output.
7
Troubleshooting Guide
If the engine does not start
-
check and use a new spark plug if needed.
(Check the spark: put the plug into the cable end and by turning
the engine you´ll see the necessary spark. Note: The plug must
touch a metal part of the engine.)
- check fuel lines.
- check for proper mechanical function by turning the
engine over.
- check that the carburetor is correctly installed.
- remove the carburetor cover from the feed side; check
the filter and blow off carburetor with compressed air
(Caution: When using compressed air, use eye protection.);
when re-assembling be
careful to maintain the proper order of
the components.
- check the vacuum feed line.
Mechanical Faults
If the engine can not be turned over easily
- a likely cause is the piston in the cylinder is seized: loosen and
unscrew the cylinder bolts.
- carefully remove the cylinder.
- visually examine the piston and crankcase to find the likely
cause of the engine’s mechanical problem.
Note: Mechanical repairs must always be completed by a
professional service department.
Replacing the reed valve:
– Loosen carb screws and remove the carburetor (be careful to
not damage the gasket)
– Loosen four M4 screws on the flange, remove the flange and
take off the reed valve (be careful to not damage the gasket)
– Loosen four M2 screws and remove the old valves, replace
them with new ones, replace all screws and tighten gently
– Be sure the gaskets are in their proper places.
A
215mm
B
140mm
C
75mm
D
89.8mm
E
89.8mm

98
Evolution GX Engine Ignition System
The spark ignition included with your Evolution® Gas engine is a modern generation electronic ignition.
It will provide excellent operation for a long time if used correctly. Here are some features that you should
be aware of.
In addition to the basic ignition functions, the unit has two safety features.
1. After 90 seconds of inactivity it automatically switches to an inactive state. In order to restart normal operation it is
necessary to turn the battery switch off and then back on. This function will preserve battery life should the switch
be left in the on position during inactivity.
2. During normal operation the battery voltage will decrease. When the voltage reaches 4.4V the ignition unit will limit
maximum rpm in the range of 3000–4000 rpm. This is an indication to land the model as soon as practical.
The electronic ignition unit requires a 4.8-volt battery source separate from your model’s radio system. A
600mAH battery will provide more than 1.5 hours of operation. The supplied battery connector is compatible
with the JR® radio battery connector.
While installing the ignition unit in your model, be careful to have all parts that are connected to the unit
and the engine situated as far as practical from the radio receiver and radio antenna. The throttle servo
should be mounted a distance of 8–12 inches from the engine. The spark plug cable must not touch any
part of the model structure, as vibration may damage the cable. If this is not practical, it will be necessary
to provide an insulation material for the cable. The ignition unit itself should be wrapped in foam rubber
to prevent engine vibration from damaging the electronics. All components must be protected from contact
with engine fuel.
Plug
Plug
Cap
Plug
Cap
Probe
BASIC PROBE AND MAGNE T ADJUSTMENT
Magnet A
Magnet A
Probe
Propeller Driver
Direction
of Rotation
Propeller Driver
Distance of probe from magnet 0:5 mm
Screw securing the connector in required position
Red
Brown
Orange
+
-
Data Out
Battery
Connector
To Battery
Switch
Magnet A position on the driver
corresponds to the
TOP DEAD CENTER of the piston.
Basic pre-ignition adjustment
is given by magnet A.
Magnet distance is 180 degrees.
Ignition
Module
Installation of the Ignition Unit
Technical data
Battery Supply 4.8–6 Volts
Current Consumption 90–120mAh at Idle
500mAh/9000 rpm
Plug Voltage 18Kv
Weight 265 g
Dimension 55x50x25mm
Sensor Magnet Space max. 0.5mm (.020”)
Plug Spark Gap .6mm (.025”)
Working Temperature -10 to 85 deg C
Installation of the Ignition UnitInstallation of the Ignition Unit Continued

Part Number Description Part Number Description
EVO30100101 Crankcase
EVO30100102 Crankcase Screws Set
EVO30100202 Front Bearing
EVO30100204 Packing
EVO30100203 Rear Bearing
EVO30100301 Rear Cover
EVO30100302 Rear Cover Screws Set
EVO30940304 Pressure Nipple
EVO30100305 Pressure Nipple Gasket
EVO30100401 Cylinder
EVO30100402 Cylinder Screws Set
EVO30100403 Cylinder Nut
EVO30100404 Cylinder Gasket
EVO30100405 Exhaust Screws Set
EVO30100406 Exhaust Nut
EVO30100407 Exhaust Flange Gasket
EVO30100701 Piston
EVO30100702 Piston Ring
EVO30100801 Piston Pin
EVO30100802 Piston Pin Retainer
EVO30100901 Connecting Rod
EVO30100904 Connecting Rod Washer
EVO30101001 Crankshaft
EVO30101101 Drive Washer
EVO30101102 Drive Washer Key
EVO30101103 Propeller Nut
EVO30101104 Propeller Washer
EVO30101105 Propeller Screw
EVO30101107 Propeller Screws Set
EVO30100306 Carburetor Flange
EVO30100307 Carburetor Flange Gasket
EVO30100308 Carburetor Flange Screws Set
EVO30101301 Reed Valve Case
EVO30101302 Reed Valve
EVO30101303 Reed Valve Screws
EVO30101304 Reed Valve Gasket-upper
EVO30101305 Reed Valve Gasket-bottom
EVO30101306 Reed Valve Strap
EVO30101307 Carburetor Screws
EVO30103313 Electric Ignition Unit
EVO3306 Spark Plug
EVO30941403 Spark Plug Washer
EVO30941404 Locking Screw
EVO30941405 Ignition Sensor Fixing Screws
EVO30100802 Reed Valve Assembly
EVO30103328 Carburetor Complete
116GX Parts Diagram 116GX Parts List