Magnum XL .25ARNV Operating Instructions Manual

The Magnum XL .25ARNV thru .36ARNV engines are single cylinder, two

cycle engines incorporating ABC piston and sleeve technology for long

life and easy break-in.  A dual needle carburetor for precise adjustments is

standard on all four engines.  All four engines incorporate a cast aluminum

rear needle valve assembly for safety.  The engine was designed by expert

engineers and built by master craftsmen using only the highest quality ma-

terials and CNC machinery.  These qualities provide the long life and de-

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

INTRODUCTION

BECOMING FAMILIAR WITH THE MAGNUM

XL .25ARNV thru .36ARNV ENGINES

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

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.  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 pre-

cautions while using it.  Please read the safety warnings below carefully.

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’ in-

struction manual or on the plans for individual mounting recommendations.

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 nut 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 safely accessible.  Do not throw

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

the engine.

N

Stand behind the engine while 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 while 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 at all times while the engine is running.

N

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

pede airflow over the engine and result in overheating and possible severe

damage to the engine.

INSTALLATION

q Engine Orientation

The Magnum XL .25ARNV - .36ARNV engines can be orientated in any posi-

tion on the firewall.  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).

OPERATING INSTRUCTIONS

XL .25ARNV - .28ARNV  and

XL .32ARNV - .36ARNV

XL .25

XL .28

XL .32

XL .36

Displacement (cc)

Bore (mm)

Stroke (mm)

Practical R.P.M.

Weight (w/Muffler)

Crankshaft Thread

1/4 - 28

1/4 - 28

1/4 - 28

1/4 - 28

(XL .36A

RNV Shown)

Pressure Nipple

Muffler

Exhaust Cone

Carburetor

Prop Washer

Prop Nut

Crankshaft

Thrust Washer

Cylinder Head

Needle Valve

Detent Spring

Needle Valve

Mount

Fuel Nipple

Crankcase

Carburetor Retaining Bolt

Throttle Arm

Muffler Thru Bolt

Fuel

Nipple

Throttle

Arm

Idle Mixture

Screw (inside

throttle arm)

Rotor

Bolt

Fuel

Nipple

Rotor

Bolt

Throttle

Arm

Idle

Mixture

Screw

Idle Stop

Screw

(XL .28A

RNV Shown)

(XL .36A

RNV Shown)

4.05

4.57

5.26

5.81

17.42

18.5

19.5

20.5

8.5

8.5

8.8

8.8

2,000 - 16,000

2,000 - 16,000

2,000 - 16,000

2,000 - 16,000

11.2

10.8

12.3

12