XTM Racing 457 PRO User guide

XTM RACING 457 PRO 6-PORT REAR EXHAUST ENGINE

6-PORT REAR EXHAUST

ENGINE WITH

TWO-NEEDLE SLIDE

CARBURETOR, SG-STYLE

CRANKSHAFT AND

PULL-START

ENGINE SPECIFICATIONS

Displacement ..................................... 4.57cc

Bore: ................................................... 18.5mm

Stroke: ................................................ 17mm

Top RPM: ........................................... 33,000rpm

Power: ................................................ 3.8hp

Weight: ............................................... 425g

CAUTION - PLEASE READ!!

INTRODUCTION

Thank you for choosing the XTM Racing 457 Pro 6-Port Rear Exhaust

engine. All XTM Racing engines are designed for high power output

and easy handling. The 457 Pro 6-Port Rear Exhaust engine features

a dual ball bearing-supported SG-style crankshaft, true ABC piston

and sleeve, two-needle slide carburetor, heat-dissipating cylinder

head, pull-start assembly and superb attention to detail and quality.

All XTM Racing engines are manufactured using CNC manufacturing

equipment to ensure every engine is produced to the exacting quality

that you have come to expect from an engine of this caliber.

BECOMING FAMILIAR WITH YOUR ENGINE

Please read through this instruction sheet in its entirety to familiarize

yourself with the features and operation of your new XTM Racing

457 Pro 6-Port Rear Exhaust engine.

Start by using the photo below to familiarize yourself with the major

components of your new engine.

XTM Racing engines will consistently give you dependable

performance and reliability and will be a source of satisfaction and

pleasure if you follow these instructions as to the engine’s proper

and safe use. You alone are responsible for the safe operation of

your engine, so act sensibly and with care at all times. This engine

is not a toy. It is a precision-built machine whose power is capable

of causing serious injury to yourself and others if abused, misused

or if you fail to observe proper safety precautions while using it.

Never use any fuel in your engine other than glow fuels

☞

specifically designed for use in model car/buggy engines. Use of

any other types of fuel can cause severe damage to the engine and/or

personal injury. NEVER USE GASOLINE OR DIESEL FUEL!

Never operate your model on any public streets. This could

☞

cause traffic accidents, personal injury or property damage.

Glow fuel engines emit exhaust vapors that are poisonous and

☞

can be dangerous to your health. It is important that you operate

your engine in a very well-ventilated area, preferably outdoors.

Before starting the engine, make sure that the throttle trim is set

☞

to the idle position. Starting the engine at any setting above idle can

cause the model to lurch out of your hands.

Due to running manufacturing changes and improvements,

your engine may differ slightly from that shown.

Should you encounter any problems with your engine, we have

☞

included a separate troubleshooting guide with these instructions

to help you solve them.

When the engine is running, there are certain parts that rotate

☞

at high speeds. Be careful not to touch the drive shafts, gears, clutch

assembly or any other moving parts. Serious injury could result.

It is normal for the engine to get very hot during operation,

☞

especially the cylinder head exhaust system. Never touch the

engine or exhaust system while they are hot.

Model car engines duce vibration when they are running. It is

☞

important to periodically check the engine mounting screws, exhaust

mounting screws and other assemblies to ensure they are tight.

Running the engine with the engine mounting screws loose can

lead to severe engine and/or chassis damage.

1

CARBURETOR INSTALLATION

FUEL RECOMMENDATION

IMPORTANT The carburetor on your engine comes preinstalled

from the factory; however, we suggest reading this section to

familiarize yourself with the steps to install the carburetor properly

should you need to remove it later for cleaning or maintenance.

❑ 1) The carburetor is held in place using the pinch sleeve and

socket-head screw already

installed in the crankcase.

Slide the base of the carburetor

into the crankcase, being

careful to keep the carburetor

perpendicular to the front of

the engine. With your thumb,

push down on the carburetor

firmly so the base of the carburetor fits completely into the crankcase

and the carburetor o-ring seals the gap between the two parts. While

holding the carburetor in place, tighten the socket-head screw to

draw the pinch sleeve into place.

WARNING Do not overtighten the socket-head screw. The screw
only needs to be tightened enough to keep the carburetor from
turning in the crankcase. Overtightening the socket-head screw
can cause severe damage to the base of the carburetor.

IDLE STOP SCREW

Fuel can make a big difference in the way your engine performs.

For the break-in period you should use a fuel specifically designed

for R/C car engines that contains no more than 20% nitromethane

and 10%-14% oil content. Once the engine has been adequately

broken in (about 45 minutes of run-time) you can switch to a fuel

containing up to, but no more than, 30% nitromethane and 10%-14%

oil. We recommend using XTM Racing fuel.

WARNING We do not recommend using fuels designed for R/C

airplane engine use. These fuels will cause the engine to overheat

and/or run erratically and severe damage to the engine will result.

GLOW PLUG RECOMMENDATION

The glow plug can make a big difference in how your engine

performs. We recommend using a "medium" or "hot" heat-range

glow plug intended specifically for performance engines like the XTM

Racing # 4 (P/N 146021) or the XTM Racing # 3 (P/N 146020)

during the break-in process. After the break-in period you may want

to use a different heat-range glow plug. Do not use glow plugs

intended for four-stroke airplane engines or glow plugs with an "idle

bar." Using the wrong type of glow plug will cause the engine to run

erratically and make it difficult to tune properly. The wrong type of

glow plug could also damage the engine. The engine includes

an XTM Racing # 4 Medium heat-range glow plug.

Please first familiarize yourself with the location of the idle stop

screw using the photo of the

carburetor on page 1. The

idle stop screw adjusts the

closure of the throttle barrel.

We recommend that the idle

stop screw be adjusted so that

the carburetor barrel stays

open about 1mm. Turning the

idle stop screw clockwise will cause the barrel to stay open more.

Turning the idle stop screw counterclockwise will allow the barrel to

close more.

EXHAUST SYSTEM

Your new engine does not include an exhaust system. The exhaust

system is typically designed for the particular car, truck or buggy that

you have, thus is usually included in the model's kit. The engine

uses a standard 1/8th scale slip-on header (held in place with a spring

around the cylinder head).

IMPORTANT For optimal power and performance, we suggest

using a 1/8 scale high-performance tuned pipe. The type of pipe

will depend on your particular vehicle and performance requirements.

WARNING ABOUT HYDRO-LOCKING

If at any time the pull-start becomes very tight or difficult to pull -

STOP! The engine has become flooded and the excess fuel must

be removed or damage to the pull-start and/or engine could occur.

To remove the excess fuel from the engine follow the steps listed:

●

Completely close the high speed needle valve (turn it clockwise)

until it GENTLY bottoms out.

●

Remove the glow plug from the cylinder head.

●

With a rag over the top of the engine, pull the pull-start cord

several times to clear the excess fuel from the engine.

●

Check to make sure the glow plug has not been fouled, then

reinstall it. If the glow plug is fouled, replace it.

●

Reset the high speed needle valve 3.5 turns out from bottom

(turn it counter-clockwise).

HIGH & LOW SPEED NEEDLE VALVES

HIGH SPEED NEEDLE VALVE:

The high speed needle valve is used to meter the air/fuel mixture at

full throttle. Using a flat blade screwdriver, turn the needle clockwise

to lean the mixture or turn the needle counter-clockwise to richen

2

the mixture. When you start the engine

for the very first time, the needle valve

should be turned in completely, then

backed out 3.5 turns. This is the factor y

break-in setting.

LOW SPEED NEEDLE VALVE:

The low speed needle valve meters the air/fuel mixture at idle and

during transition from idle to full throttle.

Turn the low speed needle clockwise to

lean the mixture. Turn it counter-clockwise

to richen the mixture. The low speed

needle valve is preset from the factory, but

minor adjustments may need to be made to suit your application:

fuel used, glow plug and environment all contribute to the setting.

To reset the low speed needle valve back to the factory

setting, follow these simple steps:

●

Open the carburetor barrel completely.

●

While holding the barrel open with your finger, use a flat blade

screwdriver to turn the low speed needle valve clockwise until it stops.

From this point, turn the low speed needle valve counter-clockwise

3 full turns. This is the factory break-in setting.

STARTING PROCEDURE

Your XTM Racing engine is equipped with a pull-starter. You should

use this to start the engine.

The following details the starting procedure for your engine.

❑ 1) If your fuel tank has a primer pump, press this pump several

times and watch the fuel as it is drawn up to the carburetor. When

the fuel reaches the carburetor, stop priming. Over-priming the

engine can cause the engine to "hydro-lock" or flood.

(See warning on page 2). Never try to start the engine

if it is hydro-locked. This could cause serious damage to both

the engine and the pull-start assembly.

If your fuel tank does not have a primer pump, open the throttle

☞

completely, cover the tip of the tuned pipe with your finger, and pull

the pull-start cord several times to draw fuel into the carburetor.

❑ 2) The engine is started by connecting the power to the glow

plug then pulling on the pull-start cord. To do this properly you should

pull the cord in short, quick, successive pulls until the engine starts.

Once the engine has started, release the pull-start cord.

IMPORTANT Never pull the pull-start cord out to its maximum

length. This may damage the pull-start assembly. Always use

short, rapid pulls. When the engine is new, it can sometimes be

difficult to turn over using the pull-starter. You may find you need

to pull the pull-starter harder than you expect. A trick to help this is

to loosen the glow plug slightly, start the engine, then remove the

glow starter and retighten the glow plug.

BREAK-IN PROCEDURE

Your XTM Racing engine is an ABC engine. The cylinder sleeve is

tapered at the top, causing resistance when the piston moves through

the top of the stroke. This is normal. When the engine heats up to

operating temperature, this resistance will decrease and the proper

clearance will be achieved. The break-in procedure will guide you

through the steps necessary to properly break in your new engine.

Please follow the steps closely.

The break-in process allows the engine parts to perfectly fit to

☞

each other and properly protect each part from premature wear. The

engine should be broken in using a good quality R/C

car fuel that contains no more than 20% nitromethane.

❑ 1) Turn the high speed needle valve out 3.5 turns from the fully

closed position and follow the starting procedure in the previous

section to prime and prepare the engine for starting. Do not adjust

the low speed needle valve.

❑ 2) Open the throttle barrel just above the idle position and

attach a glow starter to the glow plug. Start the engine following the

guidelines in step 2 in the previous procedure.

❑ 3) Once the engine starts, allow it to run for about 10 seconds

without giving it throttle. This will allow the engine to warm up. At

this point the engine should be running very "rich" and the engine will

also sound like it's running rough.

❑ 4) After the engine has been running for about 10 seconds,

remove the glow starter from the glow plug. Advance the throttle in

short, quick bursts and drive the car around for about 2-3 minutes. If

the engine is running rich enough, you should notice smoke coming

from the tuned pipe and the engine should sound like it’s running

very rough. Also, the car will barely be moving. This is what you

want for now. If there is not smoke coming from the tuned pipe,

richen the high speed needle valve. After 2-3 minutes stop the

engine by pinching the fuel line to the carburetor.

❑ 5) Let the engine cool for apximately 10 minutes, then restart it.

Set the high speed needle valve mixture to a slightly leaner setting,

about 1/8 turn more in. Repeat step 4 above, then stop the engine

and let it cool for approximately 10 minutes.

❑ 6) Repeat step 5, while leaning the high speed needle valve slightly

more each time. In all, you should run the engine a total of about 45

minutes. After 45 minutes of run-time the engine will be broken in.

Run the engine with the high speed needle valve set slightly rich,

but lean enough to power the car. At this point the engine should

hold a good setting on the high speed needle valve and you can

begin to fine tune the needle valve settings to increase performance.

IMPORTANT It is of the utmost importance that the engine never

be leaned out too much. When running the engine, you should

always be able to see a trail of smoke coming from the tuned pipe.

If you can’t, stop the engine immediately and richen the high speed

needle valve. You should also make sure there is plenty of air

flowing over the cylinder head to keep the engine from overheating.

3

FINE TUNING YOUR ENGINE

Now that your engine has been broken in, you can set the high and

low speed needle valves for optimum engine performance.

❑ 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.

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).

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.

MAINTAINING YOUR ENGINE

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.

For warranty and technical support, please contact your local distributor:

In North America:

Global Services

18480 Bandilier Circle

Fountain Valley, CA 92708

Phone: [phone]

Fax: [phone]

Email: [e-mail]

In the U.K.:

Ripmax LTD.

241 Green Street

Enfield, U.K.

EN3 7SJ

Phone: [phone]

Fax: [phone]

Email: [e-mail]

❑ 5) Restart the engine and repeat step 4 until the engine will

transition smoothly and quickly. Very slight hesitation in the

transition is normal.

North America by Global Hobby Distributors and in the U.K. by Ripmax

XTM Racing engines are distributed exclusively in

All contents copyright © 2005 Global Hobby Distributors Version 1 December 2005

4

TE001 (148310) Cylinder Head Screw Set (4) M3x16

TE2802G (148431) Cylinder Head

TE2803 (148432) Head Button

TE2804A (148433) Head Gasket - 0.10mm

TE2804B (148434) Head Gasket - 0.20mm

TE2831A (148435) Piston and Sleeve

TE2806 (148436) Wrist Pin

TE005 (148320) Wrist Pin Clips

TE008D (148325) Connecting Rod

TE2809G (148437) Carburetor Assembly - Complete

TE015 (148402) Ball Bearing - Front (HG 7x19x6)

TE011 (148334) Collet for Flywheel

TE012A (148336) Carburetor Retaining Bolt Assembly

TE2819H (148438) Crankcase

TE016A (148404) Ball Bearing - Rear (HG 13x24x6)

TE020 (148346) Exhaust Gasket

TE2817B1 (148492) Crankshaft

TE9011 (148170) High Speed Needle Valve

TE9012 (148172) O-Ring for High Speed Needle Valve

TE9013 (148174) Needle Valve Seat

TE9015A (148439) Fuel Nipple

TE9010 (148374) Idle Stop Screw

TE9009 (148441) O-Ring for Idle Stop Screw

TE28901G (148442) Carburetor Body ONLY

TE010A (148330) Upper O-Ring for Carburetor

TE010B (148332) Lower O-Ring for Carburetor

TE9002 (148362) Carburetor Barrel

TE9003 (148364) O-Ring for Low Speed Needle Valve

TE9007 (148372) Low Speed Needle Valve

TE9004A (148443) Dust Boot

TE9018 (148378) Ball Cup

TE9005 (148370) Ball Link

TE9016 (148376) Set Screw for Ball Link

TS3A-1 (148444) Pull-Start Assembly

TS316 (148445) Pull-Start Handle

TROUBLESHOOTING GUIDE AND WARRANTY
INFORMATION CAN BE FOUND ON THE BACK

OF THIS SHEET

EXPLODED VIEW DRAWING AND PARTS

LIST FOR 457 PRO 6-PORT REAR EXHAUST EN-

GINE

Numbers that start with "T" are XTM Racing

manufacturer numbers. The six-digit numbers are

provided for easy ordering convenience though

your local Global Hobbies dealer.

TS012C (148199) Pull-Start String Tube - Molded

TS313 (148447) Pull-Start Cover

TS014 (148200) Pull-Start Bolts (3)

TS317 (148448) Pull-Start Recoil Spring

TS3030 (148495) Pull-Start String and Spool

TS002 (148214) Pull-Start Cushion Spring

TS1E (148449) Backplate Assembly

TS005A (148189) One-Way Bearing

TE12228 (148451) O-Ring for Backplate

TS001C (148446) Backplate

TS015 (148201) Backplate Screws (4) 3x6

TS004 (148210) Pull-Start Shaft

P/N 146032

Version 1 12/05

TROUBLESHOOTING GUIDE

This troubleshooting guide has been provided to help you diagnose and solve most problems that you may encounter with
your XTM Racing 457 Pro 6-Port Rear Exhaust engine. Most problems encountered can be solved by carefully following the problem­cause-solution sections below. If you cannot solve the problem using this troubleshooting guide, please feel free to contact us at the
address or phone number listed at the bottom of this page.

PROBLEM CAUSE SOLUTION

1) Engine does not start A) Failed glow plug A) Replace glow plug with a new one
B) Glow Starter not charged and/or faulty B) Fully charge glow starter and/or replace
C) Idle mixture screw set too lean C) Reset idle mixture to factory setting
D) Old or contaminated fuel D) Replace with new fuel
E) Engine flooded with too much fuel E) Remove glow plug and expel fuel from cylinder
F) Air leak in fuel system and/or engine F) Replace fuel lines and/or tighten all engine bolts

2) Engine does not draw fuel A) Air leak in fuel system and/or engine A) Replace fuel lines and/or tighten all engine bolts
B) High speed needle valve fully closed B) Reset high speed needle valve to factory setting
C) Idle mixture screw set too lean C) Reset idle mixture to factory setting
D) Fuel lines kinked D) Check and straighten fuel lines
E) Defective fuel tank E) Replace fuel tank

3) Engine does not transition A) Failed and/or wrong type glow plug A) Replace with new recommended glow plug
B) Old and/or wrong type fuel B) Replace with new recommended fuel
C) High speed needle valve set too rich C) Reset high speed needle valve to leaner setting
D) Idle mixture set too lean D) Set idle mixture richer
E) Idle mixture set too rich E) Set idle mixture leaner
F) Air leak in fuel system and/or engine F) Replace fuel lines and/or tighten all engine bolts

4) Engine overheats A) Engine running too lean A) Richen high speed needle valve
B) Body too Restrictive B) Open larger vents in body to allow air to enter and exit
C) Wrong type of fuel used C) Use fuel recommended only for R/C cars
D) Engine not fully broken in D) Allow engine further break-in time

5) Engine vibrates excessively A) Engine and/or engine mounts loose A) Tighten all engine mounting bolts

6) Engine does not idle down A) Idle stop screw out of adjustment A) Adjust idle stop screw so carb barrel stays open 1mm
B) Air leak in fuel system and/or engine B) Check fuel lines, tank and engine bolts. Verify carb is

seated and tight

7) Pull-Start Slips A) One-way bearing saturated with fuel oil A) Remove one-way bearing and clean bearing and

starter shaft with rubbing alcohol
B) One-way bearing and/or starter shaft are worn B) Replace one-way bearing and/or starter shaft
C) Fuel used has too much oil content C) Use fuel with 10%-14% oil content

RETURNING FOR WARRANTY SERVICE

All XTM Racing engines returned for warranty service must be within the warranty terms as stated on the warranty card provided with
your engine. Do not return the engine to the place of purchase. They are not authorized or equipped to perform warranty work on XTM
Racing products. When requesting warranty service, please observe the following guidelines:

●

Always send the complete engine including the carburetor. The engine must

be removed from the model.

●

Include a note detailing the problem or service you are requesting. Service
cannot be provided without this information. Include your daytime phone
number in the event we need more details pertaining to the service requested.

●

You may request an estimate of services at the time you return your engine for
service. An omission of this request implies permission for Global Services to
service your engine at our discretion.

●

Include a method of payment for any service charges. If not specified, the unit
will be returned to you C.O.D.

●

Send the engine to us by United Parcel Service, Federal Express or by
Insured Mail. Postage is not refundable. Send to:

In North America:

Global Services

18480 Bandilier Circle

Fountain Valley, CA 92708

Phone: [phone]

Fax: [phone]

Email: [e-mail]

In the U.K.:

Ripmax LTD.

241 Green Street

Enfield, U.K.

EN3 7SJ

Phone: [phone]

Fax: [phone]

Email: [e-mail]