Force Engine FORCE 21 COMBUSTION MOTOR CNC EC-21RZ Manual Do Utilizador
Códigos do produto
EC-21RZ
Operating Instructions
Combustion Engine „Force 21 CNC“
Item no. 23 54 26
Prescribed use
The highly developed combustion engine you purchased is intended to be used in suitable
models. Please observe the following safety instructions and danger warnings.
models. Please observe the following safety instructions and danger warnings.
All company names and product designations contained herein are trademarks of the
respective owners. All rights are reserved.
respective owners. All rights are reserved.
General information
Dear customer, the following operating manual gives notes and information on the operation
of the engine.
Combustion engines for models are a powerful alternative to electric motors if the much louder
operating noise and the exhaust fumes do not matter in model operation.
They are, however, not so easy to handle and require special treatment before, during
and after operation. In the case of wrong treatment, the engine has a low power output,
does not run correctly, or is inoperative after only a short runtime (please bear in mind
that improper operation leads to loss of guarantee/warranty!)
As a matter of course, these operating instructions cannot impart any practical
knowledge. If you have never worked with a combustion engine, we recommend joining
a model construction club in your area.
There, you will surely find help for the first steps to a successful handling of model combustion
engines.
of the engine.
Combustion engines for models are a powerful alternative to electric motors if the much louder
operating noise and the exhaust fumes do not matter in model operation.
They are, however, not so easy to handle and require special treatment before, during
and after operation. In the case of wrong treatment, the engine has a low power output,
does not run correctly, or is inoperative after only a short runtime (please bear in mind
that improper operation leads to loss of guarantee/warranty!)
As a matter of course, these operating instructions cannot impart any practical
knowledge. If you have never worked with a combustion engine, we recommend joining
a model construction club in your area.
There, you will surely find help for the first steps to a successful handling of model combustion
engines.
Safety instructions
We do not assume liability for damage to property or personal injury
caused by improper use or the failure to observe the safety instructions.
The guarantee will expire in any such case.
Depending on the engine type and the respective model in which it is installed
(airplane, car or ship model), some of the following safety instructions might not
apply.
Keep the product out of reach of children. It is not a toy; it should be kept out of
reach of children under 14 years of age!
Before each start, ensure the safe operation of your model and of the engine.
Even normal engine vibrations can lead to the loosening of the engine and other
drive parts. Therefore, check if the engine and all drive parts sit correctly prior to
each new starting of the engine.
We recommend an appropriate liability insurance for the operation of models. A
model airplane crash or an accident with a model car might cause serious
personal or property damage. Ask your insurance agent for further information,
if the operation of the model is covered by the insurance or not.
Perhaps, a liability insurance is already included in the contributions for a model
construction club.
Never operate the engine in closed rooms. The fumes are poisonous!
If the engine is operated outside the model, a suitable test stand is to be used.
Keep children and spectators away from running engines.
For starting the engine, use a suitable starter or finger protection (airplane
models with propeller). Some engines allow a comfortable start with a so-called
pull starter.
Engine and sound absorber become very hot during operation. Risk of burns!
To stop the engine, interrupt the fuel supply or close the carburettor tap.
Never try to stop a running engine with your fingers. Risk of severe injuries!
caused by improper use or the failure to observe the safety instructions.
The guarantee will expire in any such case.
Depending on the engine type and the respective model in which it is installed
(airplane, car or ship model), some of the following safety instructions might not
apply.
Keep the product out of reach of children. It is not a toy; it should be kept out of
reach of children under 14 years of age!
Before each start, ensure the safe operation of your model and of the engine.
Even normal engine vibrations can lead to the loosening of the engine and other
drive parts. Therefore, check if the engine and all drive parts sit correctly prior to
each new starting of the engine.
We recommend an appropriate liability insurance for the operation of models. A
model airplane crash or an accident with a model car might cause serious
personal or property damage. Ask your insurance agent for further information,
if the operation of the model is covered by the insurance or not.
Perhaps, a liability insurance is already included in the contributions for a model
construction club.
Never operate the engine in closed rooms. The fumes are poisonous!
If the engine is operated outside the model, a suitable test stand is to be used.
Keep children and spectators away from running engines.
For starting the engine, use a suitable starter or finger protection (airplane
models with propeller). Some engines allow a comfortable start with a so-called
pull starter.
Engine and sound absorber become very hot during operation. Risk of burns!
To stop the engine, interrupt the fuel supply or close the carburettor tap.
Never try to stop a running engine with your fingers. Risk of severe injuries!
With airplane models with a propeller, never stand in front of or next to the engine/
propeller; there is a high risk of injury! Setting and adjustment work must be
carried out from the rear!
Make sure that no fuel leaks in an uncontrollable way during the operation of the
engine; risk of fire, explosion and burns!
Never hold any objects into moving drive parts (e.g. propeller). Do not block the
engine.
Propellers must not be repaired. Damaged propellers must be replaced!
The transmitter and receiver must be left switched on as long as the engine is
running in order to keep the model and the engine under control at any time.
Do not try to experiment with your engine. Seek the advice of an experienced
modeller or let the latter help you with the assembly.
Do not leave packaging material unattended. It may become a dangerous toy for
children.
propeller; there is a high risk of injury! Setting and adjustment work must be
carried out from the rear!
Make sure that no fuel leaks in an uncontrollable way during the operation of the
engine; risk of fire, explosion and burns!
Never hold any objects into moving drive parts (e.g. propeller). Do not block the
engine.
Propellers must not be repaired. Damaged propellers must be replaced!
The transmitter and receiver must be left switched on as long as the engine is
running in order to keep the model and the engine under control at any time.
Do not try to experiment with your engine. Seek the advice of an experienced
modeller or let the latter help you with the assembly.
Do not leave packaging material unattended. It may become a dangerous toy for
children.
Mounting the engine
The engine must be fastened firmly and free of oscillation on a stable engine support
(preferably made of aluminium). To that effect, use sufficiently dimensioned screw bolts and
secured screw nuts. The engine should be plane with the clamping surface so that the motor
flange cannot distort.
(preferably made of aluminium). To that effect, use sufficiently dimensioned screw bolts and
secured screw nuts. The engine should be plane with the clamping surface so that the motor
flange cannot distort.
Adjusting the carburettor
In general, carburettors are equipped with two independent adjustable needles. The first
needle, the full throttle needle, is located directly at the fuel connection. With this needle, the
full throttle run is adjusted.
When the needle is unscrewed, the engine is supplied with more fuel. This is called a rich
carburettor setting. When the needle is screwed into the nozzle connection, the flow cross
section is reduced and the engine is supplied with less fuel. This is called a lean carburettor
setting.
The second needle is the idle speed needle. With some airplane engines, for example, the idle
speed needle is located opposite to the full throttle needle on the other side of the carburettor.
With this needle, not only the idle speed but also the transition from idle speed to full throttle
is adjusted.
As with the full throttle needle, the air mixture is made leaner by screwing in the needle. When
the needle is unscrewed, a richer setting is achieved. The full throttle needle is to be opened
by approx. 2–3 turns. The same is to be done with the idle speed needle.
If the tip of the idle speed needle is visible through the open carburettor, the needle is to be set
in such a way that the tip of the needle starts to immerse in the counter cone when the
carburettor is half closed.
The engine can be started with the carburettor being opened by ¼. After the warming-up, the
full throttle is adjusted. The highest engine speed is adjusted by screwing in the full throttle
needle, with the carburettor being opened completely. As the engine becomes weaker during
operation, you should now unscrew the full throttle needle slightly on the “richer” side.
A too lean idle speed setting causes the engine to stop when throttling the engine or
accelerating. If the engine becomes slower in idle speed until it stops, or if it accelerates only
reluctantly, this means that the idle speed setting is too rich and must be made leaner.
Modifications to the needle must only be carried out in small steps; this applies especially to
the idle speed needle. Taking an analogue watch as an example, an adjustment by “5 minutes”
can already be too much.
A correctly set engine will always run smoothly, also at longer idle speed running times, and
will accept the throttle promptly.
If you have no experience with model combustion engines at all, we recommend the help of
an experienced modeller. You can thus prevent not only lengthy (unsuccessful) trying but also
a damaging of the expensive engine.
needle, the full throttle needle, is located directly at the fuel connection. With this needle, the
full throttle run is adjusted.
When the needle is unscrewed, the engine is supplied with more fuel. This is called a rich
carburettor setting. When the needle is screwed into the nozzle connection, the flow cross
section is reduced and the engine is supplied with less fuel. This is called a lean carburettor
setting.
The second needle is the idle speed needle. With some airplane engines, for example, the idle
speed needle is located opposite to the full throttle needle on the other side of the carburettor.
With this needle, not only the idle speed but also the transition from idle speed to full throttle
is adjusted.
As with the full throttle needle, the air mixture is made leaner by screwing in the needle. When
the needle is unscrewed, a richer setting is achieved. The full throttle needle is to be opened
by approx. 2–3 turns. The same is to be done with the idle speed needle.
If the tip of the idle speed needle is visible through the open carburettor, the needle is to be set
in such a way that the tip of the needle starts to immerse in the counter cone when the
carburettor is half closed.
The engine can be started with the carburettor being opened by ¼. After the warming-up, the
full throttle is adjusted. The highest engine speed is adjusted by screwing in the full throttle
needle, with the carburettor being opened completely. As the engine becomes weaker during
operation, you should now unscrew the full throttle needle slightly on the “richer” side.
A too lean idle speed setting causes the engine to stop when throttling the engine or
accelerating. If the engine becomes slower in idle speed until it stops, or if it accelerates only
reluctantly, this means that the idle speed setting is too rich and must be made leaner.
Modifications to the needle must only be carried out in small steps; this applies especially to
the idle speed needle. Taking an analogue watch as an example, an adjustment by “5 minutes”
can already be too much.
A correctly set engine will always run smoothly, also at longer idle speed running times, and
will accept the throttle promptly.
If you have no experience with model combustion engines at all, we recommend the help of
an experienced modeller. You can thus prevent not only lengthy (unsuccessful) trying but also
a damaging of the expensive engine.
Running in the engine
These values are based on practical experience values and are non-binding.
Recommendation: Use an already mixed brand fuel which usually contains
additional additives which are advantageous for the engine.
If you nevertheless want to mix the fuel yourself, you must use high-quality fuel
components (synthetic oil, nitromethane, methanol).
additional additives which are advantageous for the engine.
If you nevertheless want to mix the fuel yourself, you must use high-quality fuel
components (synthetic oil, nitromethane, methanol).
Before the first startup, the engine needs an initial running-in phase. Thereby, very fine
machining traces on rotating or jointly gliding components are smoothed. Special running-in
fuel usually contains a smaller amount of nitromethane.
Carefully screw in the enclosed main throttle needle (needle with fuel intake) up to the limit stop;
then open it by 2-3 turns. Turning out gives a richer mix, turning in a leaner mix. The initial
running-in phase at low speed (with fully open choke tap and extremely rich mix) should
average 2-4 tank fillings. After each engine running (tank filling), allow for a sufficient cooling
phase.
machining traces on rotating or jointly gliding components are smoothed. Special running-in
fuel usually contains a smaller amount of nitromethane.
Carefully screw in the enclosed main throttle needle (needle with fuel intake) up to the limit stop;
then open it by 2-3 turns. Turning out gives a richer mix, turning in a leaner mix. The initial
running-in phase at low speed (with fully open choke tap and extremely rich mix) should
average 2-4 tank fillings. After each engine running (tank filling), allow for a sufficient cooling
phase.
Afterwards, the mix should be made leaner step by step by screwing in the main throttle needle
and the model can already be used. The final running-in of the engine can, depending on the
model, last several hours. After this phase, you can operate the engine with full power.
and the model can already be used. The final running-in of the engine can, depending on the
model, last several hours. After this phase, you can operate the engine with full power.
Important!
With a new engine, the carburettor setting must be adjusted, from the start, as rich
as possible. It is only in the course of time that one can approximate the maximum
engine power. Now you can also properly adjust the idle speed.
A too rich carburettor setting prevents the engine from running at full power.
However, a setting that is too lean is dangerous for the engine and, sooner or
later, leads to an engine damage!
With a new engine, the carburettor setting must be adjusted, from the start, as rich
as possible. It is only in the course of time that one can approximate the maximum
engine power. Now you can also properly adjust the idle speed.
A too rich carburettor setting prevents the engine from running at full power.
However, a setting that is too lean is dangerous for the engine and, sooner or
later, leads to an engine damage!
Troubleshooting
Technical data
The technical data are details of the manufacturer; no guarantee of correctness! Subject to
change without prior notice.
Displacement: ..................... 3,46ccm
Power: ................................. 1,4kW (1,9hp)
Engine speed: ..................... 6500-29000 rpm
Bore: .................................... 16,6mm
Stroke: ................................. 16mm
Weight: ................................ 409g
Dimensions A x B: .............. 37,8 x 16mm
Dimensions C x D: .............. 85 x 112,8mm
change without prior notice.
Displacement: ..................... 3,46ccm
Power: ................................. 1,4kW (1,9hp)
Engine speed: ..................... 6500-29000 rpm
Bore: .................................... 16,6mm
Stroke: ................................. 16mm
Weight: ................................ 409g
Dimensions A x B: .............. 37,8 x 16mm
Dimensions C x D: .............. 85 x 112,8mm
Problem
The engine does not start
Engine stops after a short run-
ning time or after having discon-
nected the start battery
ning time or after having discon-
nected the start battery
Power decreases after reaching
operating temperature, the en-
gine runs inconsistently
operating temperature, the en-
gine runs inconsistently
Solution
• Glow plug defective, replace it
• Glow plug does not glow properly; check the leads
• Glow plug does not glow properly; check the leads
and start battery
• Engine gets too much fuel (kicks back); check the
carburettor setting or unscrew the glow plug and let
the engine race several times
the engine race several times
• Engine gets too little fuel (does not start); check the
carburettor setting
• Engine does not ingest any fuel; check the fuel
setting and the filters for passage and tightness or
check the carburettor setting
check the carburettor setting
• Glow plug defective, replace it
• Too high water proportion in the fuel; use brand fuel
• Too high water proportion in the fuel; use brand fuel
or keep the fuel canister closed
• Check the carburettor setting
• Carburettor, filter or fuel line dirty; clean them com-
• Carburettor, filter or fuel line dirty; clean them com-
pletely
• Loose glow plug or cylinder head
• Fuel line bent/defective; replace the hose
• Engine becomes too hot; running-in phase is not
• Fuel line bent/defective; replace the hose
• Engine becomes too hot; running-in phase is not
carried out correctly
• Change the carburettor setting (use a richer mix-
ture)
• Ensure sufficient cooling
• Engine is set too “sharp”; change the carburettor
• Engine is set too “sharp”; change the carburettor
setting
• Glow plug defective or wrong glow plug value; use
a different glow plug
• Keep the engine in a dry room with little humidity
These operating instructions are published by Conrad Electronic SE, Klaus-Conrad-Straße 1,
D-92240 Hirschau/Germany (www.conrad.com).
These operating instructions reflect the current technical specifications at time of print. We reserve the
right to change the technical or physical specification.
© 2008 by Conrad Electronic SE.
Maintenance and service
• Always use a fuel filter between tank and engine.
• Always keep the fuel canister clean.
• Only use brand fuels and synthetic oils!
• Always empty the tank after operation of the model.
• In case that a foreign body penetrates the engine, disassemble the latter and rinse it
• Always keep the fuel canister clean.
• Only use brand fuels and synthetic oils!
• Always empty the tank after operation of the model.
• In case that a foreign body penetrates the engine, disassemble the latter and rinse it
generously with fuel. Afterwards, clean all parts with a non-corroding oil.
• Do not disassemble the engine unnecessarily.
• Check the engine for damages and wear when it has not been used for a longer period of
• Check the engine for damages and wear when it has not been used for a longer period of
time.
• Keep the engine in a dry room with little humidity.
A
B
C
D