User Manual

The Magnum XL .61RFS is a single cylinder, overhead valve, four stroke
engine incorporating ringed piston technology for long life and high power
output. A dual needle valve carburetor is employed for easy and precise
mixture adjustments. A polished aluminum muffler is included 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 qual-
ity materials and CNC machinery. These qualities provide the long life and
dependability you have come to expect from an engine of this caliber.
If you are familiar with the operation of model engines or just can’t wait to
run your new engine, please read through the Quick Starting Guide in-
cluded. This guide will help you get started right away and includes some
good recommendations, also. We do recommend reading through this in-
struction sheet in its entirety to familiarize yourself with the features and
operation of your new engine. We have also included a Troubleshooting
Guide should you encounter any problems. Please use the photo below to
familiarize yourself with the components of your new XL .61RFS engine.
Magnum model engines will consistently give you dependable perfor-
mance and reliability and will be a source of satisfaction and pleasure if
you follow these instructions for the engine’s proper and safe use. You
alone are responsible for the safe operation of your engine, so act sensi-
bly 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.
☛
Keep spectators, especially small children, at least 20 feet away from
the engine while it is running.
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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.
☛
Use the recommended size propeller and follow the proper procedure
for mounting the propeller. Use an adjustable wrench to tighten the pro-
peller nut and the safety nut. Do not use pliers.
☛
Inspect the spinner, propeller and propeller nuts on a regular basis,
looking for any signs of nicks, cracks or loosening.
☛
To stop the engine, adjust the throttle linkage to completely close the
throttle barrel and therefore cut off the fuel/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.
☛
While the engine is running stand behind the engine to make any ad-
justments to the needle valves. Do not reach over or around the propeller.
Do not lean towards the engine. Do not wear loose clothing or allow any-
thing to be drawn into the spinning propeller while the engine is running.
☛
Do not use tight fitting cowls over the engine. They can restrict air
from flowing over the engine and result in engine damage from overheating.
❑ Engine Orientation
The Magnum XL .61RFS engine can be orientated in any position on the
firewall. Keep in mind that if you mount the engine inverted, carburetor
adjustments will need to be made differently and the fuel tank may need to
be lowered. (See fuel tank size and orientation to carburetor on next page.)
Engines mounted inverted tend to run richer during idle and transition to
full throttle, and are generally more difficult to set up and tune properly.
❑ Engine Bolts and Firewall Requirements
The XL .61RFS engine should be mounted to a glass filled or metal motor
INTRODUCTION
BECOMING FAMILIAR WITH
YOUR XL .61RFS ENGINE
ENGINE INSTALLATION
WARNINGS
OPERATING INSTRUCTIONS
Bore: 24.8mm
Stroke: 20.6mm
Displacement: .61cu.in.
Practical RPM: 2,000 - 12,000
Weight w/Muffler: 15.5oz.