Magnum XL 1.20RFS Instructions Manual

Single Cylinder Ringed Four Cycle Engine

M A G N U M   X L   1 . 2 0 R F S

The Magnum XL 1.20RFS is a single cylinder, overhead valve four stroke

engine incorporating ringed piston technology for long life and a dual needle

carburetor for precise adjustments.  A polished aluminum muffler is in-

cluded to keep the noise to a minimum without sacrificing power.  The

engine was designed by expert engineers and built by master craftsmen

using only the highest quality materials and CNC machinery.  These quali-

ties provide the long life and dependability you have come to expect from

an engine of this caliber.

INTRODUCTION

BECOMING FAMILIAR WITH THE MAGNUM

XL 1.20RFS

Before attempting to operate your new engine, please read through this

instruction sheet in it’s entirety.  This will help you familiarize yourself

with the features and operation of your new engine.  Use the photos below

to identify the major component parts of your new engine.

SPECIFICATIONS

Displacement.............................................19.6cc (1.22cu.in.)

Bore............................................................................30.4mm

Stroke..........................................................................27.5mm

Practical R.P.M.................................................2,000 - 11,000

Weight (w/Muffler)....................................................31.08oz.

Crankshaft Thread Size...............................................5/16-24

WARNING!

Magnum model engines will consistently give you dependable performance

and reliability and will be a source of satisfaction and pleasure if you fol-

low these instructions as to the engine’s proper and safe use.  Do not let

pleasure turn into injury and/or tragedy!  You alone are responsible for the

safe operation of your engine, so act sensibly and with care at all times.

This Magnum model 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.

N

Keep spectators, especially small children, at least 20 feet away from

the engine while it is running.

N

Mount the engine securely in the airplane or on a suitable engine test

stand to run the engine.  Follow the mounting instructions in your kits

instruction manual or on the plans for individual mounting recommenda-

tions.  Do not clamp the engine in a vise to test run it.

N

Use the recommended size propeller and follow the proper procedure

for mounting the propeller.  Use the correct size wrench to tighten the

propeller nuts.  Do not use pliers.

N

Inspect the spinner, propeller and propeller nuts on a regular basis,

looking for any signs of nicks, cracks or loosening.

N

To stop the engine, adjust the throttle linkage to completely close the

throttle barrel and therefore cut off the air supply.  You can also pinch the

fuel line to stop the engine, but only if it is accessible.  Do not throw

anything into the spinning propeller or attempt  to use your hands to stop

the engine.

N

Stand behind the engine when it is running to make any adjustments

to the mixture controls.  Do not reach over or around the propeller.  Do not

lean towards the engine.  Do not wear loose clothing or allow anything to

be drawn into the spinning propeller when the engine is running.

N

If you need to carry your model while the engine is running, be con-

scious of the spinning propeller.  Keep the airplane pointed away from you

and others.

N

Do not use tight fitting cowls or oversized spinners as these can im-

pede airflow over the engine and result in overheating and damage to the

engine.

INSTALLATION

q Engine Orientation

The Magnum XL 1.20RFS can be orientated in any position on the fire-

wall.  Keep in mind that when the engine is mounted inverted, carburetor

adjustments will need to made differently and the fuel tank may need to be

lowered.  (See tank size and orientation to carburetor on next page).

Rocker

Cover

Cylinder

Head

Thrust

Washer

Prop

Nuts

Prop

Washer

Crankcase

Exhaust

Pipe

Pressure

Nipple

Muffler

Intake Pipe

Carburetor

Choke

Assembly

Detent Spring

High Speed

Needle Valve

Fuel Nipple

Idle Stop

Screw

Throttle

Arm

Low

Speed

Needle

Valve

Crankcase

Breather

Return

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