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NT-16 / NT-18 / NX 3.0 Starting Instructions
Please read carefully before operating.

Please follow the steps below to prepare, start and break-in your nitro engine. If you have any questions at any time please give your local CEN authorized retailers a call or E-mail us at [email protected] for technical support.

Step 1. Charge Glow Ignitor
The nitro engine requires a glow ignitor to light the glow plug when starting the engine. The ignitor takes approximately 12 hours to fully charge. You should always make sure the ignitor is fully charged when starting your engine.
Step 2. Install 12 AA Batteries
The transmitter and receiver pack both need to have batteries installed into them before doing anything else to the truck, eight batteries in the transmitter and four batteries in the truck. If you start the truck before installing the batteries, it may run away from you. You may use NiMh or NiCd in addition to alkaline batteries. Be sure to completely charge rechargeable batteries before installing.
Step 3. Check your Fuel
Make sure you are using proper high quality fuel with the correct nitro percentage (20-30% Nitro). Fuel that is left in an open bottle will go bad quickly. Always keep fuel in an airtight container.
Step 4. Install your Air Filter
Some models may already have the air filter installed. If yours has not, find it in the box and install it onto the carburetor. It comes with a zip tie to use to secure it to the engine.

Step 5. Standing your Antenna Up
Insert the antenna wire through the antenna mount, through the antenna tube, then insert into tube mount. The antenna wire may be longer then the tubes, if so, DO NOT cut the wire. Let excess wire hang freely
Step 6. Turning on your Transmitter
ALWAYS turn on the transmitter first, followed by the receiver. Never turn off the transmitter or the reciever while the engine is running. Always turn off engine first then the receiver, followed by the radio.
· Remember… You should always turn the transmitter on first and turn it off last.
Step 7. Check for Proper Operation of Servos
With the transmitter and receiver all turned on (engine not running), make sure your steering, throttle and forward/reverse servos are working correctly. Make sure when you turn the wheel on the transmitter left the wheels turn left, and then check the right side. When you pull the throttle trigger the carburetor should open, when you push the trigger back the brakes should be applied. If your servos are moving / responding slowly, you need to check for weak batteries.
Step 8. Checking the Transmitters Range
Before driving your truck, test the range of your radio system. Walk away from the truck to equal the furthest distance you plan to drive your truck. Make sure all the servos operate correctly. Do not operate the truck if you notice any transmitter problems.
Step 9. Filling the Fuel Tank Up with Fuel
Using your fuel bottle, squeeze the bottle and insert it into your container of fuel, Let go of it and the suction will suck the fuel into your fuel bottle. Next lift the cap on the tank and fill of up with fuel.
Step 10. Prime the Engine with Fuel
To prime the fuel system, put your finger over the exhaust outlet on the exhaust pipe. Pull the pull cord a few times and watch for the fuel to fill the fuel line. Stop once the fuel reaches the carburetor. * If you notice the fuel line is not priming, you may need to open the carburetor to allow the fuel to flow through.
Step 11. Starting the Engine
Do not start the engine until you have read and understood all the directions. By starting the engine you have indicated that you have checked the transmitter and servos ECT. for proper operation. With transmitter and receiver all turned on, attach your fully charged glow ignitor onto the glow plug. With one hand holding the glow heater, use your other hand to give the pull starter quick short pulls. (Pulling the pull start cord too far will brake the spring inside and void the warranty) The engine will start much easier if you hold ¼ throttle on the transmitter.
Step 12. Keeps the Engine Running
A new engine may not idle smoothly until it’s correctly broken in
(Break-in procedures found in step 14). Use the transmitter to keep the engine reved up just enough to keep it running. If the engine stalls you may need to raise the idle slightly.
Step 13. Proper engine break-in is very important to achieve the highest possible performance and reliability
Allow yourself some time to properly break-in the engine. This is one of the most important steps to follow so take your time. Do not run the engine at high RPMs until it is completely broken in. It is usual for the engine to stall, run inconsistently, and even foul glow plugs during the first couple of tanks. If this is happening to yours, don’t worry about it too much. It is a normal step in running any nitro powered R/C car. All of this will go-away after your engine is broken in.

Step 14. Break-in Procedures
To begin break in procedures for your new engine, simply idle 3 tanks of fuel. Allow the engine to cool down completely between tanks. On the 4th and 5th tank start driving the truck around slowly. On the 6th tank start leaning it out and making final tuning adjustments.

Break in:
Top: 3 1/2 turns out
Bottom: FLUSH

After Break in:
Top: 3 turns out
Bottom: 1 - 1/2 turn in from FLUSH

* These settings are approximate due to the differences in climate, fuel nitro %, and fuel oil %.

Step 15. Running the First Tanks in the Truck
By now you should have fully broken in your engine. Hopefully you took your time and broke the engine in correctly. When driving the truck drive it on flat smooth surface like the street first. Make sure that your steering trim is adjusted correctly and that the truck tracks straight. There is also a dual rate adjustment for the steering. This will adjust how much steering throw you have. (How much the wheels actually turn)
Step 16. Engine Tuning (adjusting the high-end needle)
Now your truck and engine should be up and running well. The overall performance of the engine is determined by how lean you run the engine. The “leaner” the engine, the faster it will go, and the hotter it will run. You want to find the point where it’s running very well with lots of power, but not running too hot. If you don’t see a light stream of blue smoke from the exhaust it may be to lean. You then need to richen up the top end. (Screw with brass sleeve around it) All of the engine adjustments listed above is not certain because of variations in type of fuel, brand, %nitro, humidity, elevation, ECT. Engine life is varies on the operating temperate. Preferred engine temperature is around 220-240’F.

Step 17. Fine Tuning low-speed Mixture and Idle screw.
The low-end needle should be close to correct setting at 1 ½ turns in from flush. The best way to check the bottom end adjustment is by listening to the way the engine idles. If the engine idle rises the bottom end is lean, if the engine idle drops its too rich. When making any needle adjustments make sure you do it in small adjustments.

Step 18. Installing the Body Clips
Align the holes in the body with the body mounts. Then install the pins through the holes in the mounts. You may adjust the height of the body by lowering body clips.

Step 19. This is the most important step of all
Drive your new CEN NT-16 / NX 3.0. Have fun and drive safely. Show your model the same respect as you would driving your full size vehicle.

Steps to follow after operating.

Step 1. Burn all the fuel out of the engine by keep the engine running until the engine will not start.
Step 2. Take the glow plug out and put a few drops of after run oil into the engine. After run oil is available at most hobby shops.

Precautions that Must be Taken
· Because there are electrical components on the truck it should not be ran through water, wet grass, mud or anything else that may get water inside the electronics.
· Avoid leaving the glow heater on the glow plug any longer then needed to start. The heater will burn the glow plug out if left on too long.
· Do not drive the truck when your radio is showing low battery voltage.
· Do not drive your truck at night, on public streets, or in large crowds.
· Do not drive if the servos are slow or unresponsive, this usually means your batteries are low, replace with new
· Always use common sense when driving your NT-16 / NX 3.0. Abusive driving will only result in poor performance and many broken parts.
· User accepts full responsibility for the use of this product.

Most common mistakes made by beginners:
1. Most beginners pull the pull starts out too far and bend the spring. Pull the cord no more then 8 inches out. If you get to the end of the cord you will bend the spring and it will not recoil correctly.
2. Avoid pulling the pull starter if you engine is flooded. You know your engine is flooded when the cord becomes very difficult to pull. To get excess fuel out of the engine simply remove the glow plug and turn the engine upside down. Give the pull starter a couple of pulls and excess fuel will come out.
3. If you leave your glow heater on you glow plug when you not trying to start it the glow plug will burn out very quickly. Only put the heater on when you’re ready to start the engine.
4. Make sure you unbundled the antenna wire and stand it up using the supplied antenna straw.

General information

High-end Mixture Controls the fuel mixture at high R.P.Ms

Low-End Mixture Controls the fuel mixture at low R.P.M.s

Lean This term is used to describe the amount of fuel entering the carburetor. Lean means less fuel. Turn carburetor needles clockwise for a leaner setting. Running too lean will damage your engine.

Rich Setting This term is used to describe the amount of fuel entering the carburetor. Rich means more fuel. Turn the carburetor needles counter-clockwise for a richer setting.

Glow plugs CEN engines come standard with a CEN G70429 glow plug. You may also use most standard or short glow plugs. Always make sure you are using the copper washer that is supplied with each glow plug.

Air Filter The air filter is very important to an engines life. Keeping it clean and oiled will increase performance and engine life.

Pull Starter When removing the pull starter be careful with the spool, which is spring loaded. Use a small screwdriver to gently push the spool off the output shaft.