You're newly purchased Ryobi 720FR from JAG Engine is an excellent R/C engine value!nbsp;nbsp; This engine is virtually bullet proof and should give you many years of service with minimal care required. The FR, (Factory Reconditioned), series of engines have been run by the Ryobi factory in Chandler, AZ to make certain that all is well. This is the main reason that we can offer such an outstanding value.nbsp; Ryobi engines have a chrome bore and a ring with an oval cross section. It takes from 8 to 12 hours of running time to fully break them in. Although they run great right from the start they just get better and better the longer you run them.
We have left the kill switch wire on the coil so that you may put a switch between this wire and a wire that is grounded to someplace on the engine or motor mount. For safety purposes, this will allow you to stop the engine manually by killing the ignition at any time you wish without relying on your radio control. It is also possible to set the carburetor so that you can kill the engine merely by moving the throttle control to the extreme low end. Some modeling events require the ability to positively stop the engine either manually or by remote control or both.
If you elect to connect the electrical “kill”
switch to a remote control channel, be sure to keep at least 4 inches of insulation
between any metal connections to the engine and any radio system components.
That means do not use solid wire throttle or kill switch pushrods. Always use
a section of plastic between the carburetor or kill switch connection and the servo
connection. I always try to get 4” of plastic “Nyrod” in there
somewhere. Remember high tension ignition noise can transmit through anything
that is metal. The use of resistor spark plugs significantly reduces the
strength of this noise. The Ryobi front-mounted magneto does a very good job
of isolating this noise. However, good practices in installation with any
spark ignition engine can go a long way if other radio problems appear.
NOTE: KEEP ALL WIRES ON ENGINE AS FAR AWAY AS IS
POSSIBLE FROM BATTERIES, SERVOS, ANTENNA AND RECEIVER FOR BEST INTERFERENCE FREE
OPERATION. DO NOT USE METAL PUSH RODS FOR CARB ACTUATION.
USE PLASTIC NYRODS. We have had excellent results with all type of R/C radios when
these instructions are followed.
Installation and starting Instructions
·
Use 4 ounces of good two-cycle oil with one gallon of gas. This gives a 32:1 ratio which is a good
conservative mixture. We have gotten by with
as little as 50:1 (2.5 oz oil).
·
Hook the gas tank feed line to the 90-degree gas intake tube on the top of
the carburetor.
·
Make certain that the straight tube next to the needle valves is closed off
with fuel line and a plug in the end of the fuel line.
·
Close the choke lever and prime the engine by flipping the prop about 4 to 6
revolutions. Be sure that the airplane is
sufficiently restrained during the choking operation because the engine could start. If the engine fires even once in this condition,
stop flipping and open the choke half way.
·
Start your Ryobi with a standard 12 volt starter. Open the choke all the way after the engine has
run for a few seconds. Adjust the high speed
needle valve (H) for maximum RPM and then adjust the low speed (L) needle for the best
reliable idle. The high speed valve is the
one next to the letter H on the base of the carburetor.
Both needle valves usually are open about 1- 1/8 turns to begin with. Gasoline engines are very stable and, once set,
should need VERY LITTLE subsequent adjusting unless a dramatic climate change or a
different size prop is installed. I have been
flying one engine for two years and made no needle valve adjustments at all during this
time. I have, however mixed 3 separate
gallons of gas/oil of the same ratio and the engine has not noticed any difference.
·
Stop the engine by shorting the kill switch or closing the throttle all the
way. NEVER throw anything into the propeller
to stop the engine.
·
MAKE CERTAIN THAT THE KILL SWITCH IS TURNED OFF! When the kill switch is on
it will short the ignition system off.
·
We recommend using the APC props from 16 x 8 to 16 x 12 or 18 x 6. Also Zinger 18 x 6 to 18 x 8 and Master Airscrew
Classic up to an 18 x 6. We have run props up
to 20 x 6 and even a 22 x 10. The engine does have a lot of torque to pull larger props at
slower speeds.
· 12 to 17 pound airplanes seem to work best for this engine although one of our customers is flying a 24 pound 110 inch Cub on floats and gets off the water with ease and flies great. Light wing loadings will carry more weight.