3W 110i R2 User manual

ENGINE MANUAL
110i R2 / 110i R2 CS
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110i R2 / 110i R2 CS Engine Manual
Dear customer,
Thank you for placing your confidence in 3W. Our long experience (since 1985) in designing and
producing model airplane engines, ranging from single up to six cylinde r, has been utilized to
provide you with the best engine possible. Our in-house engineer has been designing two and
four stroke engines for gasoline and diesel for 38 years. We are continually looking at new
technologies and working on new designs. Please be assured that we at 3W always strive to
provide you with engines that are s t ate of the art.
You can count on your 3W engine to have:
• a high level of precision
• high torque in the low rpm range
• excellent running characteristics
•a long life
• lots of power
• And a 36 month conditional warranty.
We wish you plenty of fun and success with your new 3W engine.
Sincerely,
The 3W T eam
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110i R2 / 110i R2 CS Engine Manual
Limited Warranty
We grant a 36 month warranty from the date of purchase. This warranty is limited to the replacement
of defective p ar ts that are a direct result of faulty material or manufacturing. No claim concerning
a defect caused by non-compliance with ins t allation or operation instructions, mishandling,
unsui t able sp are p ar ts nor unskilled re pairs will be acknowledged. Please ask your dealer to fill
out a warranty certificate for you at the time of purchase. Impor t ant: Keep this certificate in a safe
place as this warranty will not be honored without it. The original receipt is also required.
The safe operation of the engine is our primary concern. Therefore any alteration, modification
or addition to the engine is not recommended and will void your warranty immediately.
In case of defect during the period of garantee, return this product to your nearest 3W -Dealer or to 3W -Germany
direct, at your cos t s. The garantee is limited to the value of the product. The guarantee does not cover any damage
caused by misuse or neglect, acciden t s, abrasion, exposure to extreme temperatures, solven t s, acids, wate r, normal
wear and tear or damage by common carrier.
Warning!
This engine is not a toy! Serious injury and /or death can occur from its misuse! READ and
become familiar with this entire instruction manual. LEARN the engine's applications,
limitations, and possible hazards.
When working on the engine(s) it is strictly prohibited to block the piston respectivly
crankshaft from moving by using a tool touching / hitting the piston crown / top.
Reason:
Distortion of the crown / top where the tool touches / hits the piston, material structure will be
changed as well as the ou t side diameter / conture of the piston.
What could happen:
Hole in the piston and / or piston will size a f ter a running time which cannot be determind.
To block the cranksha ft and / or piston from moving a tool has to be used clamping the propeller
hub onl y.
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110i R2 / 110i R2 CS Engine Manual
Important!
For your safety and for the safety of those around you -- also to learn what is required to main t ain your warranty -
we strongly advise you to read this entire manual carefully BEFORE you s t art using the engine.
Safe Operation and 3W's Conditional W arranty
For safe operation and to main t ain your warranty you must:
• Have a properly designed engine box on your model
• Mount the engine correctly
• Provide adequate air flow and cooling for the engine
• Provide adequate air flow and cooling for the exhaust
• Use an approved propeller and spinner
• Drill the propeller correctly
• Balance the propeller correctly
•T ighten the propeller bolts correctly and check them regularly
• Properly mount your ignition to avoid overheating
• Use the correct battery and regulator (if applicable) for your ignition
• Use the correct switch for your ignition
• Use an appropriate fuel t ank, plumbing lines, and ins t allation
• Use the appropriate fuel for break in and a f ter break in (gas and oil)
• Insure adequate filtering of your fuel
• Main t ain your engine properl y, keeping it clean, etc.
• Use a pre-flight check list before flying your model
• Secure your model properly when s t arting
• Not use your fingers or hand to s t art your model
• Adjust your carburetor correctly
• Not adjust your carburetor while the engine is running
• Insure that your s p ark plug is in good condition and is secured correctly
• Insure that your ignition wires are not frayed and are protected
• Insure that your ignition cap is securely mounted
• Keep all people behind the line of the prop
• Do not put anything (i.e., fingers, body p ar t s, objec t s, et al) into the ro t ating propeller
• Keep children awa y. All spec t ators should be kept a safe dis t ance away from the running engine.
•W ear proper ap p arel. Do not wear loose clothing, gloves, neckties, jewelry, or neck straps for your radio
which may get caught in the moving propeller.
• Always wear eye protection when s t arting the engine.
• Do not operate this engine if you are under the influence of any drugs, alcohol or medication that could a f fect
your ability to use the engine properl y.
Disclaimer
We cannot control how safely our produc ts will be used. And, therefore we do not accept any responsibility for
damage, or injury from their usage.
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110i R2 / 110i R2 CS Engine Manual
Engine Installation
The engine should be mounted on a motor box that will in turn mount to the fuselage. A quadrilateral
shape (gradually increasing in size as it goes away from the motor) provides the best circulation
of air. The reason for using a motor box rather than mounting the engine directly to the fuselage
is that the cylinder(s) need enough room around them to provide proper airflow over and away
from them
The motor box should be sti ff enough to prevent engine vibration and it should also have a solid
firewall. The firewall of the motor box should be made from 1/4" aircra ft plywood for engines up
to 106cc, or 3/8" aircra ft plywood for engines in the 150cc class. For builders experienced with
making composite motor boxes; a com p arable strength should be at t ained.
It is absolutely vi t al to ensure a tension free mounting of the engine. The surface that the engine
is mounted on must be on an even plane (i.e., a flat and level surface) so that there is no strain
on the engine i t self. Again, this is a vi t al and critical requirement to avoid distorting the crank case,
ruining the engine, and voiding your warranty.
Mount the engine to the motor box with high tensile bol t s. Once mounted you now have a sub-
assembly that you can mount to your fuselage. S p acers can be made from hardwood dowels (3/4"
to 1") or machined aluminum bar stock to adjust your down and side thrust. These sp acers should
go between the motor box and fuselage and not the motor box and engine.
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110i R2 / 110i R2 CS Engine Manual
It is strictly prohibited:
To mount the engine directly onto sp acers for the following reasons:
a. If the sp acers are too long and/or not sti ff enough the engine could vibrate leading
to the cranksha ft s t arting to twist, further leading to the crank case being destroyed.
b. If sp acers are used to adjust the side and/or down thrust and this sp acing no longer
provides an even plane (i.e., a flat and level surface) the crank case will be distorted,
leading to the cranksha ft s t arting to twist, further leading to the crank case being
destroyed.
To mount the engine directly onto a large (wide) former or firewall for the following reason:
a. If the cylinder(s) is/are too close to this wide former or firewall, the floating air cannot
p ass freely over and then away from the cylinder(s). Cavi t ating hot air can/will overheat
the engine.
Engine Cooling
A proper cooling system is vi t al for any engine. An air cooled engine requires an appropriately
sized air in t ake. Also to keep this air cooling process working the incoming air must be exhausted.
Further, the exhaust air outlet should be four times (4X) the size of the cool air in t ake.
Example:
•10 square inches of air in t ake area would require
•40 square inches of exhaust air outlet area
It is up to you to insure that the air flows freely to, over, and away from, the hot cylinder(s) and
mu f fler(s). Please refer to Engine Ins t allation for motor box considerations, and to the following
ti ps on ba f fling.
Baffling
Deflecting of the air (ba f fling) to and over the cylinder(s) is highly recommended for engine cooling.
The idea is to get all of the cool air that is coming through the air in t ake opening(s) to hit the middle
of the cylinder(s) directl y, and then be forced over the cylinder(s), creating turbulent air moving
through the cylinder(s) fins. The freely flowing, but directed and turbulent air between the fins
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110i R2 / 110i R2 CS Engine Manual
provides the maximum cooling for an air cooled engine. Without ba f fling (meaning wood or
composite dampers that direct the airflow) the air will t ake the p ath of least resis t ance. Some
incoming air will bounce o ff the cylinder(s) and the rest will escape around the cylinder(s) without
coming into con t act with the cylinder(s).
Engine in pusher operation:
Impor t ant note! When engines are used operating in pusher configuration cooling ge ts critical and
special attention has to be given to an e f fective cooling method. A good cooling system layout
depends on the actual location (position) of the engine in the fuselage.
Operating temperature
To be able to check the cylinder head temperature ( CHT ) a thermo element has to be installed which fits
under the spark plug ( M 10 thread ). Optimum operating temperature range : 180°C - 220°C. In this range
piston, spark plug and combustion chamber will be free of remains. Maximum temperature of 270°C should
not be exceeded. During a certain time at full speed the temperature could be 250°C.
Colour of the spark plug should be : light or middle brown. A grey / gray colour is a typical sign for over
heating. Temperatures above 270°C are critical and over 300°C, piston can seize and could completely
damage the engine.
Temperatures below 180°C create remains ( carbon ) on the piston crown. Increasing remains hit the cylinder
and cause abnormal running noises ( knocking ) which will increase the load of the needle bearings and can
destroy them. Under extreme conditions the crankshaft can break and a complete damage of the engine will
be the result.
Rear induction
Carburetors, whether front or rea r, require a steady supply of fresh air. The best way to supply
air to a rear carburetor is by ins t alling an air scoop. Some have thought to drill holes into the
fuselage near the carburetor area rather than creating an air scoop for the carburetor. This does
not work, it fact it will create a vacuum e f fect that will draw the air away from the carburetor! Again,
you should ins t all an air scoop into the front of the plane which will supply air into the fuselage.
This air will then need to flow out of the fuselage. Drill exit holes into the rear area of the fuselage
for this purpose. Impor t ant: The interior of the fuselage must be sealed to prevent damage from
gasoline that sprays from the carburetor. Use a thin epoxy or other appropriate fuel proofing
method. Do not overlook this step as gasoline will melt some materials like S tyrofoam very quickl y.
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110i R2 / 110i R2 CS Engine Manual
Ignition
Consideration needs to be given to the placement of the electronic ignition module. A void placing
the module in the p ath of hot air. Mount the ignition module using the four supplied rubber gromme ts
so as to create a 1/16" gap between the ignition module and the mounting surface. Without this
1/16" gap the ignition module can overheat. Impor t ant: If the electronic ignition overhea ts it will
malfunction (e.g., backfiring or shutting down).
Ignition details:
• The red cable is positive (+)
• The ignition timing has been set at our factory
• When fitting a new ignition it is impor t ant to achieve the correct coordination of the sensor(s)
to the magne ts
Refer to our special ignition description for further information
Canister mufflers
To prevent damage to the header(s) a flexible support bracket is required to mount the canister(s).
The location for this bracket should be at the canister's center of gravit y. 3W canisters have a
reinforcement ring at this location.
We suggest creating two com p artmen ts in the front section of the fuselage by ins t alling a horizon t al
tray. Fuel t anks, batteries, and other equipment can be mounted on top of this tray; the canister(s)
being ins t alled below it. Close o ff the lower com p artment at i ts rear with an angled former. Locate
this former 1" behind the back of the canister(s). Next cut a hole in the bottom of the fuselage just
under the rear of the canister(s). In this way the air coming from the front of the model can flow
over the canister(s) and then be deflected by the angled former so as to exit through the hole in
the fuselage. Do not forget to reinforce around this hole.
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110i R2 / 110i R2 CS Engine Manual
Important:
This exit area needs to be four times (4x) as large as the intake area.
Propellers
• Only use propeller brands and sizes that are approved for your engine
• The propeller blades must be of the same length
• The propeller must be flat (Y ou can check for flatness by putting the propeller on a level
surface. The maximum di f ference of the blade heigh ts should be no more than 1/64".)
• The propeller ti ps must have an identical shape. This is especially impor t ant when using
3 or 4 blade propellers.
•Y ou must use a drill press to drill your propeller.
•Y ou must drill the propeller from the rea r.
• A drill guide is recommended, but the propeller washer can be used as a drill template. (Fix
the propeller washer onto the propeller in the center-bore using a bolt and nut. Drill one
hole; put one of the propeller bolts into the hole. Continue until the last bolt is used.)
• If you cannot hand tighten all of your prop bolts easily then you have not drilled the propeller
correctl y. This can lead to sheared propeller bol t s.
• Balancing your propeller is absolutely critical to the health of your engine. Y ou must keep
your propeller balanced. (Propeller balancers are available from DUBRO, and others.)
• Always remember that when the engine is running every person must s t ay behind the line
of the ro t ating propeller; never to the side or the front!
Carburetor settings
Before each engine is shipped it has to p ass QC and is then test run. We do a basic adjustment
of the carburetor needles at that point.
highspeed needle H: 1
low speed needle L: 1
Important: Do not remove the carburetor spring as the spring hel ps keep the carburetor butterfly
aligned properl y. Merely release the ends of the spring so that it no longer holds the butterfly
closed.
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110i R2 / 110i R2 CS Engine Manual
Carburetor Linkage
Included with your engine is a me t al bracket to extent your carburetor pushrod horn. Fix this
bracket onto the carburetor horn with a 2.6m machine screw and nut. Then solder the arm in place.
Refer to the at t ached illustration.
Note: The use of a so ft pushrod for the throttle (plastic or nyrod) is not recommended. Use a me t al
or carbon fiber pushrod with a plastic ball joint or plastic clevis at each end. This will keep your
RPM much more consistent and accurate around idle where it really coun t s.
Engine Break In
• Use a 2-stroke petroleum based oil (preferably ashless) as this type of oil has a good honing
e f fect which hel ps to break in the engine
• Use a mixture of 32-1 or even 30-1
• Use this fuel mixture for approximately 2-3 hours of run time
• Use a high Oc t ane unleaded fuel (from 92 Oc t ane is ideal)
We suggest s t arting the break in process of the engine on a test s t and; for approximately one
hou r. This time should be used to get familiar with the engine. Do not run the engine at full throttle
for more than ten seconds during this test s t and break in. The reason for this is that you are not
getting the normal cooling e f fect that you would if the engine was in a model that was flying.
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