Duratrax TORQ 21 User Manual

You are the proud owner of a DuraTrax engine – designed to provide
easy starts and all the power you'll need for thrilling R/C action.

The following instructions contain information you'll need to break-in,
operate and maintain your new engine like a pro. Read and follow them
carefully, and your engine will provide a long life of strong, dependable
performance.

• Model engine fuel is poisonous and must be kept in a clearly marked
container, stored away from the reach of children. Avoid getting fuel into
your eyes or mouth.

• Because model engine fuel is highly flammable, it should also be kept
away from anything that might cause it to ignite (including open flames,
excessive heat, or any objects and materials which could produce a
spark). Smoking must not be permitted near the fuel.

• R/C model engine exhaust, like that of automobile engines, contains
deadly carbon monoxide. Do not run the engine in enclosed spaces –
operate it only in open, well-ventilated areas.

• Your engine will become very hot as it runs. Touching any part – particu­larly the muffler (silencer), cylinder head or exhaust header pipe – could
result in a serious burn. Avoid contact with the engine until it has cooled.

• Protect onlookers – especially small children – by making sure that
they remain at least 20 feet (60 meters) away while you start the engine.

• This engine was designed only to power R/C model vehicles and
should not be used for any other purpose.

• Never pull the starter cord out more than 10 inches (25cm). To rewind
the cord, continue holding the handle and let the recoil action pull it
smoothly back into the starter unit. Do not abruptly release the handle.

The High-Speed Needle

The “high-speed” needle is sticking up from the side of the carb. It is
located in the brass housing, just above the fuel inlet. It controls the fuel
to air mixture of the carb. The needle is pre-set for break-in from the fac­tory at 2-1/2 turns out from the fully closed position of the carb. Once

CARBURETOR SETTINGS

ADDITIONAL PRECAUTIONS

FOR YOUR SAFETY

INTRODUCTION

®

ENGINE INSTRUCTIONS

ENGINE INSTRUCTIONS

Warranty

• DuraTrax®will warranty this engine for 90 days after the pur­chase date from defects in materials or

workmanship. DuraTrax
will either repair or replace, at no charge, the incorrectly made
part.

• Make sure you save the receipt or invoice you were given
when you bought your engine! It is your proof of purchase and
we must see it before we can honor the warranty.

• To return your Torq 21 for repairs covered under warranty you
should send your engine to:

Hobby Services

1610 Interstate Drive

Champaign, Illinois 61822

Attn: Service Department

Phone: [phone]:00 am - 5:00 pm Central Time M-F

E-mail: [e-mail]

Repair service is available anytime.

• After the 90 day warranty, you can still have your Torq 21
repaired for a small charge by the experts at DuraTrax’s
authorized repair facility, Hobby Services, listed above.

To speed up the repair process, please follow these instruc­tions:

Send written instructions which include: a list of all items returned,
a THOROUGH explanation of the problem, the service needed
and your phone number during the day. If you expect the repair to
be covered under warranty, be sure to include a proof of date of
purchase (your store receipt or purchase invoice). Also be sure to
include your full return address.

the engine is broken-in, the high-speed needle would typically run from
2-1/2 to 3 turns out from closed, depending on the weather, humidity and
altitude above sea level. To richen turn the needle counterclockwise, to
lean turn the needle clockwise.

The Low-Speed Needle

The “low-speed” needle is the screw in the carb body, opposite the throt­tle arm (see picture on previous page). It controls the fuel to air mixture at
low throttle settings. There is a simple way of adjusting the low-speed
needle correctly called the “pinch test.” With the engine at idle, pinch the
fuel line and listen to how the engine speeds up or slows down. If the
engine increases its speed for about 2 or 3 seconds and then loses speed,
the needle is set correctly. If the engine loses RPM quickly, it is set too
lean and the low-speed needle needs to be opened (counterclockwise)
to richen the mixture. Pinch again

to check the mixture. If the engine takes

longer than 4

seconds to slow down, lean (clockwise) the low-speed

needle and then pinch again to check the mixture.

The Throttle Stop Screw

On the front of the carburetor, there is a black screw. This is called the idle
stop screw(see picture on previous page). This increases or decreases
the idle RPM without changing the fuel to air mixture. The barrel should
be approximately 1.5mm (between 1/32" and 1/16") from fully closed.

To insure long life and good performance from your Torq .21 engine,
you MUST break-in the engine. The break-in period is critical for long
life of the internal parts of the engine. This should be done over the first
5 or 6 tanks of fuel.

Some Things To Remember During Break-In:

1. Run with the body off. This will keep the engine cooler.

2. Keep the air cleaner on at ALL times

3. Run on a smooth, hard surface. An empty parking lot is perfect.

4. Use the same fuel that you will use for normal running.

5. Resist the urge to accelerate and decelerate the vehicle quickly.

6. Break-in puts stress on the glow plug and you can burn it out dur­ing break-in. Make sure you have an extra plug or two on hand.

7. Do NOT overheat the engine. You can check the head tempera­ture by using one of the temperature gauges that are available or
by putting a drop of water on the top of the cylinder head. If the
water boils away immediately, shut off the engine and allow it to
cool. If it takes more than 10 seconds to boil away, the engine is
at proper running temperature for break-in.

Before running, please, read this manual thoroughly to familiarize your­self with this engine.

There are several simple steps to starting the engine:

1. Install a glow plug if one is not in your engine. This threads into the

top of the cylinder head.

2. Fill the tank almost to the top. Leave a little air at the top of the tank.

3. Prime the engine by turning the flywheel on the engine. Watch the

fuel go through the line and when it gets to the carburetor, turn the
flywheel one more full revolution.

4. Open the high speed needle valve exactly 3 turns out (counter-

clockwise) from fully closed. The high-speed needle is sticking
up from the carburetor inside the brass housing. All of the car-

buretor settings are adjusted with a flat bladed screwdriver. If you
have previously run the vehicle, keep the same needle valve setting
that you used on your last run.

5. Start the engine by pulling the recoil - Use short, quick pulls. DO

NOT pull the recoil starter’s string to the end. You only need 10 inch­es of pull to start the engine.

If the engine does not start after several pulls, sometimes it is helpful to
start the engine at around half throttle. Have a friend pull back on the
throttle some while you start the engine. This may be an indicator that
the low speed needle setting needs to be adjusted. When the engine
starts, immediately return the throttle to idle. If this is not done the
engine can over-rev and cause engine damage. If the engine is diffi-

cult to turn over with the recoil starter, especially if it is brand new,
loosen the glow plug a half turn before starting the engine. This
allows some compression to escape, but the engine will still start.

Make sure you tighten the glow plug after the engine starts. If the
recoil starter is still difficult to pull, the engine is flooded – there is too
much fuel inside the engine. Remove the glow plug and air cleaner,
then turn the engine upside down and pull the recoil 5 or 6 times. This
will clear the engine of fuel, and you will notice the recoil pulls easier.
Replace the glow plug and repeat the starting procedure.

Fuels

Use fuels that are specially formulated for car and vehicle engines.
DuraTrax Red Alert fuel is specially formulated for engines like the Torq .21.

How To Stop Your Engine

You may have been wondering how to stop the engine. All you have to
do is pinch the fuel line that runs to the carburetor and from the bottom
of the fuel tank. Pinching this will restrict the fuel flow and the engine
will quit within a few seconds. You can also touch the flywheel with the
tip of your shoe through the hole in the bottom of the chassis.

The First Tank

Your first tank of fuel should be running the engine at a very rich high­speed needle valve setting. This allows the fuel to carry as much oil as
possible into the engine to lubricate the internal parts during the break-in.

1. Open the needle valve 2-1/2 turns from fully closed (counterclockwise).
This is factory set already, but check it to make sure. When closing the
high-speed needle, close the needle until you feel some resistance.
DO NOT overtighten or you will damage the engine.

2. Start the engine.

3. Once the engine is started, open the high-speed needle valve
around 1/8 turn at a time, finding the setting where the engine just
barely runs. This may take a few times adjusting the needle, run­ning the vehicle away from you and back, then adjusting the nee­dle. The engine will perform sluggishly and stall from time to time

- that is normal.

4. Run the vehicle back and forth at medium speeds, slowly acceler­ating and decelerating the vehicle.

5. After a minute or two of running, make sure the engine is not over­heating by putting a drop of water on the cylinder head and watch­ing it boil away. If it boils away within 10 seconds, stop the engine
and allow it to cool. Open the high-speed needle around a 1/4 turn
before starting again. This is a good habit to get into every time
you run to ensure that the engine does not overheat during any
run. Looking at the smoke that comes out the exhaust is also an
indicator of how rich or lean the engine is running. If there is a
good amount of smoke coming out of the exhaust, then chances
are good that you are running rich.

6. Run the vehicle back and forth at a medium speed until the tank is
almost out of fuel. Do not allow the tank to run out of fuel. This
leans out the engine and can cause overheating (See How To
Stop Your Engine).

7. Stop the engine and allow the engine to cool before the second
tank. This normally takes around 10 minutes.

Tanks 2-6

Turn in the needle valve (clockwise) around 1/12 turn from the previous
setting. Run the vehicle back and forth. You should notice that the
engine will perform better during each run. Stop the vehicle periodical­ly to check for overheating. If it is too hot, stop the engine. Wait for it to
cool, then open up the needle valve 1/4 turn and restart. After the 6th
tank, you should be near to the peak performance of the engine.

RUNNING THE ENGINE

BREAKING IN THE ENGINE