Now that your engine has been broken in, you can set the high and
low speed needle valves for optimum engine performance.
WARNING
Be careful never to lean out the engine too much.
Remember that the lubricants for your engine are suspended in
the fuel. If you lean out the fuel mixture too much you will also be
lowering the amount of lubricant entering your engine. Less lubricant
means more chance of your engine overheating and possible
engine failure.
SETTING THE HIGH SPEED NEEDLE VALVE:
❑
1) Start the engine and remove the glow starter from the glow
plug. Allow the engine to warm up for about 10 seconds.
❑
2) After the engine has warmed up, drive the car as you normally
would. If the engine seems to be running rich, lean the needle valve
about 1/16 of a turn at a time until the desired setting is achieved.
Always make sure you run the engine slightly rich - you want to be
able to see a slight smoke trail at all times.
☞
To get more power from your engine you can use fuels containing
up to 30% nitromethane. We must caution you, though, that once
you run the engine with increased nitro you may not get satisfactory
results if you decide to go back to a lower nitro content.
If you use
fuels containing 30% nitro, we suggest running a colder
heat-range glow plug; otherwise the engine may run erratically.
SETTING THE LOW SPEED NEEDLE VALVE:
❑
1) Start the engine and lean out the high speed needle valve as
per the previous steps. Close the throttle until the engine slows
down enough so that the clutch is disengaged and the wheels don’t
turn when the car is lifted from the ground. Allow the engine to idle
for about 10-15 seconds.
☞
If necessary, adjust the idle stop screw to raise or lower the
idle speed.
❑
2) While holding the car off the ground quickly open the throttle
in a short burst. If the engine just stops running as soon as the
throttle is advanced, the low speed needle valve is too lean and the
engine is not getting enough fuel. With the engine stopped, richen
the needle valve about 1/16 of a turn (counterclockwise).
❑
3) Restart the engine and repeat step 2 until the engine will
transition smoothly and quickly. Very slight hesitation in the
transition is normal.
❑
4) If you quickly advance the throttle and the engine seems to
be very rich during transition (i.e., lots of smoke coming from the
tuned pipe and very rough sounding), the low speed needle valve is
too rich and the engine is getting too much fuel. With the engine
stopped, lean the needle valve about 1/16 of a turn (clockwise).
❑
5) Restart the engine and repeat step 4 until the engine will
transition smoothly and quickly. Very slight hesitation in the
transition is normal.
To keep your engine operating at peak performance there are some
basic maintenance procedures that need to be performed on the
engine on a regular basis:
●
After you are finished running the engine for the day, pinch the fuel
line to stop the engine. This will allow the engine to burn any excess
fuel out of the crankcase.
●
Remove the air filter element and wash it thoroughly in warm water
and a small amount of liquid detergent. After it's clean, allow it to
dry, then reoil it and install it back into the air filter housing.
Never
run your engine without an air filter installed.
●
Remove the glow plug from the engine and squirt several drops of
high-quality after-run oil into the glow plug hole. Pull the pull-start cord
several times to distribute the oil throughout the engine, then reinstall
the glow plug. The after-run oil will prevent the inside of the engine
(especially the crankshaft bearings) from rusting.
●
Clean the outside of the engine using a heavy brush and nitro car
cleaner, then dry the engine, using a rag or compressed air.
●
Check the engine's cylinder head bolts and backplate screws after
each day of use to ensure that they're tight. This will prevent air
leaks from causing erratic engine performance.
FINE TUNING YOUR ENGINE
MAINTAINING YOUR ENGINE
❑
6) Now drive the car as you normally would for a while to get a
feel for how the engine reacts to throttle. Now that you know the
proper way to tune the engine, you can make slight adjustments to
the needle valves until you are satisfied with the performance.
IMPORTANT
We suggest using a temp gun to frequently check
the operating temperature of your engine during use. The optimal
operating temperature is between 210º and 240º. Do not let the
engine exceed 270º. If the engine exceeds 270º, stop the engine
immediately and retune the carburetor to a richer setting.
4
In North America:
In the U.K.:
For warranty and technical support, please contact your local distributor:
Global Services
18480 Bandilier Circle
Fountain Valley, CA 92708
Phone: (714) 963-0329
Fax: (714) 964-6236
Email: [email protected]
XTM Racing engines are distributed exclusively in
North America by Global Hobby Distributors and in the U.K. by Ripmax
All contents copyright © 2005 Global Hobby Distributors Version 1 December 2005
Ripmax LTD.
241 Green Street
Enfield, U.K.
EN3 7SJ
Phone:
(0) 20 8282-7500
Fax: (0) 20 8282-7501
Email: [email protected]