Xray NT18 Instruction And Safety Manual

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CONTENTS

Safety first 3
Parts and equipment 5
Installation 8
Starting the engine 9
Operating the engine 12
Engine break-in 13
Carburetor adjustment – overview 14
Carburetor adjustment – before putting the car on the track 16
Carburetor adjustment – at the track 18
Fine-tuning the carburetor 19
Engine troubleshooting 19
Engine care 21
Warranty 22
Servicing the engine 23
NT18 Engine parts 24

Congratulations on your purchase of the high-performance NT18 0.8cc nitro-powered engine.

Developed for highest performance and excellent reliability, this engine represents the perfect combination of manufacturing
quality and race-winning experience.

The XRAY NT18 0.8cc engine has the following features:

• uses standard model car fuel

• standard glowplug design

• durable construction

• adjustable, dual-needle, slide carburetor (aluminum)

• large, blue-anodized billet aluminum heatsink cooling head

Internal combustion (or "nitro-powered") engines require some basic knowledge and understanding, as well as important
safety considerations.

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CONTENTS

!! READ & UNDERSTAND BEFORE OPERATING THE ENGINE !!

!! READ & UNDERSTAND BEFORE OPERATING THE ENGINE !!

SAFETY FIRST

This engine is NOT A TOY, it is a precision-manufactured machine. This machine can injure to you or other nearby, and can
also damage property. It is very important to pay attention as indicated in this manual. Improper use of the machine can be
very dangerous.

You alone are responsible for operating your engine safely; act with discretion and pay special attention at all times.

• Carefully read and fully understand all of the safety instructions and engine operation instructions before you operate
your engine.

• Keep these manuals in a place so you know where they are at all times.

• Follow the instructions carefully.

The information in this manual will help to prevent injuries to users and other as well as protecting objects from damage.

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Example of graphic indications:

Warning or caution

The illustration indicates the contents of the warning or cautions.
This graphic means be careful of high temperatures.

Actions are prohibited

The actions prohibited are indicated in or near the illustration.
This graphic means do not touch.

Compels or instructs
certain actions

You must follow the instruction carefully.
This graphic means "compulsory."

GRAPHIC INDICATIONS

The following words and graphic indications are used throughout this manuals.
Be sure you fully understand these meanings before reading the text.

Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderated injury,
or damage of objects nearby.

DO NOT TOUCH

COMPULSORY

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This section illustrates the parts of the NT18 engine, and also describes fuel, glowplug, and air filter that you will use in the
operation of this nitro-powered engine.

PARTS AND EQUIPMENT

Air Filter

Fuel Inlet

Main Needle Valve

Idle Speed Screw

Flywheel

Clutch Bell

Crankshaft

Crankcase

Low-speed Needle

Throttle

Head (Cylinder Head)

Glowplug

Air Intake

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Air Filter

Do not run engine without an air filter!
The air filter protects the engine from the intake of dust and other contaminants. A properly maintained air
filter is essential to the life and performance of the engine. Use proper air filter oil with your air filter. The oil
softens the foam element and traps dirt more easily. We strongly recommend that you clean and re-oil the air
filter after every 1 hour of runtime (even if the filter looks clean) to maintain proper engine performance and
avoid engine damage. To clean the air filter parts (including the foam filter element), wash the parts in hot
soapy water, and rinse thoroughly with clean water. Dry the parts with a clean towel or compressed air (use
safety eyewear). Oil the foam element with proper air filter oil.

Exhaust System

We recommending using only the XRAY-supplied exhaust system for best performance.

Fuel

For break-in and general running, use high-quality, market-available model car fuel containing 20%
lubricant and 15~30% nitromethane by volume ratio.
Although you can obtain more power by increasing the nitromethane content, it will shorten engine
life.

Glowplug

The type and quality of glowplug used for your engine has a substantial impact on overall performance
and reliability. We strongly recommend glowplugs by XRAY. Glowplugs are consumables and the life of
plug depends on several factors and manners of use.

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Starter Box

You must start the engine by first spinning the clutch flywheel. We strongly recommend using the
#104300 HUDY Micro Start-Box, which is specifically designed for starting the NT18 engine.

STARTING & SUPPORT EQUIPMENT

Glowplug Starter

A glowplug starter is required to ignite the glowplug for starting. We recommending using a high­quality, battery-operated glowplug starter from a reputable manufacturer.

Glowplug Wrench

A glowplug wrench is required for removing/installing the engine glowplug. We recommend using a
high-quality glowplug wrench such as the #107581 HUDY Wrench-Glowplug.

Screwdriver

A small flat-blade screwdriver is required for adjusting the carburetor. We recommend using high­quality tools such as those offered by HUDY.

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If you break in your engine by using a propeller, never use a propeller that has any cracks, scratches, or even
the slightest signs of breakage.

This model engine is designed exclusively for installation into model cars.
Never use it for any other purpose. It may cause personal injury or mechanical failure.

Fix the engine firmly to the model, using tough bolts/nuts or screws with locking components/features that will
prevent them from loosening. Do not clamp the engine in a vise.
To test the engine, use a durable engine test stand available from hobby sources such as model shops.
If not affixed properly, the engine may jump off the stand during operation and cause personal injury or
mechanical failure.

In order to avoid ear damage, use an effective silencer (muffler) for sound reduction.

Exhaust gas emits annoying noise to surrounding people.
Pay attention to location and time of use.

Before mounting the engine into the chassis, check that the bottom surfaces of the engine mounts blocks are flat. This is
important to avoid any distortion of the crankcase, and to optimize heat dissipation through the chassis.

Hint: To flatten the bottom part of the mounted engine mounts, attach the engine mounts to the engine, then rub the
bottom of the mounts on a piece of sandpaper until there is full-surface contact.

Mount the engine on the chassis and align the clutch pinion(s) with the gear(s). Adjust the gear mesh.

Hint: Use a piece of paper between the pinion and the gear, tighten the engine mounting screws and remove the paper. This
should give you approximately 0.1mm of play in the gear mesh.

After connecting the fuel and pressure lines and hooking up the throttle linkage to the carburetor, check that the carburetor
opens and closes smoothly without binding. If there is any restriction of movement, adjust the throttle linkage or the position
of the carburetor on the engine.
If your transmitter has throttle servo trim adjustment (a.k.a. "end point adjustment"), adjust the range of motion of the throttle
linkage for full throttle and full brake.

INSTALLATION

PROHIBITION

COMPULSORY

COMPULSORY

COMPULSORY

COMPULSORY