Fantom FR21 User manual

50201 SILVER STREET
VICKSBURG, MI 49097
PH. 269-649-9583
FAX [phone]
WWW.FANTOMRACING.COM

FANTOM® FR21 / FR27
Thank you for purchasing a Fantom® FR21 or FR27 Racing Engine.Your new engine has been developed to provide superior
performance and longevity for both racing and sport applications. To attain the maximum enjoyment from your new engine, even
if you have prior experience with engines, please review the following information – you won’t be sorry – knowledge is power!
Table of Contents
1. TABLE OF CONTENTS 21. ENGINE MAINTENANCE
2. TOOLS & SUPPLIES / REMOVING OLD ENGINE 22. ENGINE MAINTENANCE / CAUTION STATEMENT
3. INSTALLING FR 21/27 23. NEWS / WARRANTY
4. INSTALLING FR 21/27 24. FR 21/27 REPLACEMENT PARTS
5. INSTALLING FR 21/27 / ENGINE OPTIONS 25. FR 21/27 REPLACEMENT PARTS
6. ENGINE OPTIONS / OPERATIONAL GUIDELINES 26. FR 21/27 REPLACEMENT PARTS
7. OPERATIONAL GUIDELINES
8. OPERATIONAL GUIDELINES
9. OPERATIONAL GUIDELINES
10. OPERATIONAL GUIDELINES
11. STARTING YOUR ENGINE
12. STARTINGYOUR ENGINE / BREAK-IN (HEAT CYCLING)
13. BREAK-IN (HEAT CYCLING)
14. BREAK-IN (HEAT CYCLING)
15. BREAK-IN (HEAT CYCLING)
16. BREAK-IN (HEAT CYCLING) / NEEDLE VALVES
17. NEEDLE VALVES
18. NEEDLE VALVES
19. NEEDLE VALVES / ENGINE MAINTENANCE
20. ENGINE MAINTENANCE
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TOOLS & SUPPLIES REQUIRED FOR EASY INSTALLATION
• 3/32 Hex Wrench • 5/64 Hex Wrench • 1.5mm Hex Wrench
• 2.5mm Hex Wrench • 5/16 Nut Driver • 5.5mm Nut Driver
• Needle Nose Pliers • Piston Stop (Clutch Tool) • Phillips Screwdriver
• Flat Blade Screwdriver • Hobby Knife • Thread Lock
• New Fuel Line • Filter Oil • After-Run Oil
• Throttle Return Spring • Air Filter • Manifold
• Small Nylon Tie Straps (air filter) • Large Nylon Tie Straps (manifold) • Pipe Wire Mount
REMOVING THE OLD ENGINE (If Applicable)
1. If your new Fantom engine is replacing an existing engine, you will need to remove your old engine from the vehicle, following
your vehicle’s instruction manual. If this is a new installation, please refer to this manual for installation instructions.You
may also want to refer to your vehicle’s instruction manual for any special instructions not covered in this manual.
2. If applicable, remove your old engine from the original engine mount and set it aside to use with your new Fantom engine.
3. If applicable, disassemble the stock clutch parts from your original engine, noting the order of their removal, as you will need
to install them on your new Fantom engine in the exact reverse order that you removed them from your original engine.
Clutch removal and installation is best accomplished by using a clutch tool (piston stop tool);this can be obtained at a quality
hobby shop.This tool allows you to fully tighten or loosen the clutch nut by keeping the piston from moving up and down or
allowing the crankshaft to turn. Never wedge anything inside your engine’s exhaust or attempt to grip the shaft with pliers
as these techniques will permanently damage internal and external parts.
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INSTALLING THE FANTOM® FR21 OR FR27
1. Remove the glow plug and install the piston stop (clutch) tool.
2. Install your clutch parts onto your Fantom engine in the reverse order of their removal from the stock engine. If you are
installing a new clutch, follow the instructions that came with the clutch. Before installing the clutch nut, apply a small drop
of thread lock to the clean shaft threads; this will prevent the nut from coming loose. Because clutch shoes are important for
good engine performance – and are relatively inexpensive – replace them with a new stock set (if you are installing the
original clutch).
3. Remove the clutch tool and reinstall the glow plug.
4. Loosen the 5.5mm carburetor-securing nut and position (angle) the carburetor in the same position as your original
carburetor was set at, or as your vehicle’s instruction manual suggests.While pressing the carburetor firmly to the crankcase,
retighten the securing nut. Make certain that the throttle ring ball mount is properly positioned like your original carburetor,
or as instructed in your vehicle’s instruction manual; if it isn’t, loosen the small setscrew on the throttle ring and rotate the
ring to the desired location; retighten the setscrew.
5. A leaking fuel tank can cause severe problems with your engine’s performance.Therefore, inspect the tank for leaks and
replace it, if needed. Install a new fuel-line, leaving plenty of extra length; it will be cut to the proper length once the engine
is installed in the chassis.
6. Install the manifold seal to the exhaust port at the rear of the engine – making sure it’s fully seated.Follow this by fully seating
the manifold (sold separately) over the seal. Because there are so many applications for this engine, please consult your
vehicle’s manual for manifold recommendations. More than likely you will be able to use your stock manifold if this is a
replacement application.
7. Secure engine to the stock engine mount(s), using the original four bolts … add a drop of thread lock to all four bolts at this
time (clean them first).
8. Position the engine within the chassis and secure it from the underside with the four original bolts.Add a drop of thread lock
to all four bolts at this time (clean them first).Lightly tighten the bolts prior to checking the gear mesh.While holding the clutch
bell gear in place, rock the spur gear back and forth; it should measure between 0.003 and 0.005 inch of endplay. Slide the
engine back and forth in its mounted position until you achieve the proper gear mesh. DO NOT adjust the gear mesh too
tight or too loose – the gears, clutch, and engine can be severely damaged.
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Once the proper gear mesh is obtained, fully tighten the four engine mount bolts (under the chassis) and recheck the gear
mesh … one more time.
9. Snap the throttle ball cup to carburetor using needle nose pliers.
IMPORTANT: At this point, we recommend installing a throttle return spring (available at any quality hobby dealer).This is
a safety precaution, to prevent the engine from running past the idle position, in the event that you lose radio contact with
the vehicle, or have any type of radio failure. This situation could cause dangerous uncontrolled wide-open operation,
resulting in injury to person(s) and/or property damage. Install the return spring in a manner in which the throttle returns to
idle position, when the radio is off.
10. Cut the fuel tubing to the proper length and attach to carburetor inlet nipple.If possible, route the fuel line away from sources
of high temperature (e.g., tuned pipe, manifold, and cylinder head). Heated fuel may vaporize in the fuel tubing causing
erratic engine operation – cool fuel runs better.
11. Should you use a stock or aftermarket tuned pipe?We recommend using a Fantom WORKS tuned pipe.OurWORKS PIPES
produce much better performance than a stock pipe. Besides, they sound “killer” – a much raspier tone – not to mention the
cool appearance.Your Fantom dealer has these in stock or they can order one for you from one of our distributors.They are
available in natural team finish (part #FAN20014 single stage or FAN20016 dual stage) or shiny nickel finish (part
#FAN20015 single stage or FAN20017 dual stage).You can find more details on our pipes by visiting our web site
www.fantomracing.com. If you decide to use the stock pipe, attach it to the manifold using the stock silicone coupler and new
tie straps. If you use an aftermarket pipe, follow the installation instructions included with the pipe. After completing the
connection between the manifold and pipe, secure the pipe to the chassis with a standard wire mount. Finish the tuned pipe
installation by connecting the fuel tank pressure line to the pipe’s pressure fitting.
12. With the radio turned on, adjust the throttle and brake trim settings (refer to your radio manual for details):
•Set the radio trims so the throttle closes and opens fully – take your time with this procedure.
•Make sure that the transmitter throttle trigger is in the fully pulled back position at the same time the carburetor opens
completely (100%); when the throttle trigger reaches its neutral position, the carb must be simultaneously closed (0%).
In other words, you don’t want the carburetor fully open when your throttle trigger is only partially back; likewise, you don’t
want the carburetor fully closed before the trigger is in the neutral position. Faulty adjustments can damage the throttle
servo and/or make the engine act like it isn’t running properly.
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13. Install the air filter (sold separately). Make sure to oil the air filter.Use quality air filter treatment oil such as our Fantom Filter
Fluid™ / Filter Wash™ kit (part # FAN20111). Use a small tie strap to hold the air filter housing to the carburetor; these are
available from your local dealer or hardware store.
CAUTION: Never run your engine without an air filter. Rapid and permanent damage will result – which is NOT covered by
warranty.
Check all of your work, and read the rest of this manual (twice) to ensure that you completely understand the operational
characteristics of your new FR21 or FR27 Racing Engine.
ENGINE OPTIONS
Your FR21 / FR27 can be modified to work in optional configurations, by referring to the following information and part numbers.
1. Your FR21 or FR27 was built with a standard glow plug head button, which is best suited for off-road and/or high torque
applications.For on-road and/or high RPM applications we offer an optional turbo style head button, as well as a turbo glow
plug.The following optional head buttons and glow plug are available:
•FAN10422 .21/.27 Turbo Glow Plug
•FAN10440 .21 Turbo Head Button
•FAN10442 .27 Turbo Head Button
2. To modify the FR21 or FR27 (non-pull start models) for pull start operation, the following parts are available:
•FAN10404 Standard Crank with Pull Start Stub
•FAN10406 Pull Start Assembly
•FAN10407 Pull Start One-Way Bearing
•FAN10408 Pull Start One-Way Bearing Shaft
•FAN10409 Rear Plate for Pull Start
•FAN10417 Rear Plate Screws for Pull Start
•FAN10420 Pull Start Assembly Screws
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3. To modify the FR21 or FR27 (pull start models) for non-pull start operation, the following parts are available:
•FAN10410 Rear Plate for Non-Pull Start
•FAN10414 Gasket Set
•FAN10419 Rear Plate Bolts for Non-Pull Start
ENGINE OPERATIONAL GUIDELINES
This section covers important information useful in understanding the what, how and why of your new engine.
To get a full understanding of the remainder of this manual, it is important that we cover some basic principles first.Please make
sure you fully understand this section of the manual before proceeding.
Your new Fantom engine is built using the latest ABC technology (aluminum, brass, chrome). Expansion of the piston is
controlled by the percentage of silicon in the aluminum alloy; by matching the piston expansion to the expansion of the chrome-
plated brass cylinder-sleeve… both at normal operating temperatures (220º-290º F), the best running-fit can be obtained. (This
subject will be covered in more detail, later in the manual, in the “Break-In” section.) The cooling fin area of the cylinder head
regulates the temperature.
When a carburetor mixture is set properly, the temperature of the engine should be of little concern. The flash point of certain
modern lubricants found in high quality fuels is generally a minimum of 700º F; meaning as long as you are using high quality
fuel, your engine is protected even in extreme temperature conditions… IF THE AIR-FUEL MIXTURE IS NOT SET LEAN.
Unfortunately, over the years it has become customary to set the main needle valve by engine cylinder head temperature (usually
called temperature tuning); however, this is a bad practice. Temperature tuning can lead to overly rich or overly lean needle
settings – both can damage an ABC-type engine. Depending on the operating conditions (e.g., weather conditions, altitude,
surface you are running on, fuel type, etc.), we have found that the FR21 and FR27 cylinder head temperatures (taken with a
temperature gun; aiming down inside at the glow plug area of the cylinder head) will generally range between 220º and 290º F;
however, do not “temperature tune” to these temperatures.
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Tune the engine following the guidelines set forth in the “Setting The Needle Valves For Optimum Performance” section of this
manual, and consider the engine temperature a secondary issue. It is OK to check your engine’s temperature, as a reference
point, but do not “temperature tune” your FR21 or FR27.
IMPORTANT: Just because the engine is designed to run up to 290º F, do not lean the primary (main) needle valve to achieve
this head temperature, unless your operating conditions dictate it! It’s OK to run the engine this temperature ONLY if the air-fuel
mixture is properly set for the operating conditions thatYOU are running in. Also, don’t allow your engine to run too cool – you’re
not protecting its longevity! Operating the engine “blubbering rich” will cool the cylinder-sleeve to the point where the piston
will begin to rub excessively in the pinch-zone, because the cylinder-sleeve is not hot enough to expand to its intended designed
operating size.The pinch-zone is that necessary area around the top of the tapered cylinder-sleeve, where the piston comes in
contact, creating the necessary seal for proper combustion chamber compression. Excessive rubbing due to under-expansion
of the cylinder-sleeve produces pinch-zone wear. Pinch-zone wear produces combustion gas blow-by when the engine is up to
normal temperature. Combustion gas blow-by produces loss of power…the number one reason that piston and cylinder-sleeve
assemblies must be replaced.
IMPORTANT: Pinch-zone wear, resulting in loss of compression, is NOT covered by warranty.
We have no control over what brand of fuel you use, and/or the way you operate your engine.Your FR21 or FR27 is built using
the latest ABC technology, and will last just as long as any other brand of ABC type engine, as long as it is used in accordance
with this instruction manual, therefore it is your responsibility to operate your engine properly, to obtain the longest usable life
possible.
The Effect of Fuel
Different fuels drastically affect the way your engine will run. One manufacturer’s 30% nitro blend isn’t necessarily the same as
another’s – there are many variables: the type of oil (synthetic or castor), the amount of oil (% in the fuel blend), the oil blend (%
synthetic, %castor), and oil quality will require a different needle valve setting for any engine. With this in mind, here are some
rules to follow when fuel-tuning your engine:
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• Lower oil content and/or lower nitro content require leaner needle settings.
• Higher oil content and/or higher nitro content require richer needle settings.
• High oil content and/or low nitro content fuels are generally better for engine longevity.
• Low oil content and/or high nitro content fuels provide better engine performance, but reduce its longevity.
• By reducing the oil content in the fuel blend many properly tuned nitro engines will operate at a slightly reduced cylinder
head temperature. Don't misinterpret reduced cylinder head temperature as protection against engine damage; to the
contrary, less oil content will not protect the engine as well as higher oil content. The less-oil/cooler engine temperature
phenomena is beyond the scope of this manual, however, the fact remains: Reduced oil content (10%, 9%, 8%, etc.) can
lead to premature engine failure … if the air/fuel mixture becomes lean.
Although not all are directly related to fuel, the following list includes the most common causes for lean mixtures:
1. The primary needle valve is set too lean.
2. Incorrect gearing - placing too much load on the engine leads to increased head temperature, producing a lean setting.
3. A leak in the fuel system can produce a lean run from an otherwise correct needle setting.
4. Hot, humid weather conditions can produce a lean mixture setting as head temperatures rise from an otherwise correct
needle setting.
In the final analysis, if you choose to use lower oil content fuel, you may gain performance advantages, but longevity will be
sacrificed. Also, in low oil content fuel, there simply isn't enough lubricant present in the fuel-blend to defend against rapid
temperature rise (due to out-of-control friction) from a lean mixture...you have sacrificed your margin for error against massive
engine damage by running less oil.
The Effect of the Weather
Weather conditions also have an effect on how well your engine performs:
•High air temperature
•High humidity
•Low barometric pressure
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