16
to come out the vent line! Re-connect the fuel lines and you are
ready to start the engine.
❑
44) When using a glow engine it is best to seal the battery hatch
to keep exhaust and fuel residue out of the fuselage. The reason
we built a hatch into this airplane was to provide access to the
battery compartment when using an electric motor. Obviously,
you do not need access to that area. We recommend simply tack
gluing the hatch in place with a couple small tabs of glue. Then
seal over the seams with either clear tape or white covering ma-
terial (not supplied).
❑
45) 2-STROKE THROTTLE PUSHROD
a) The first step is to install your throttle servo in the fuselage,
using the rubber grommets, eyelets, and screws that came with
the servo. Mount the throttle servo in the front opening of the
servo tray, with the servo control arm to the front.
b) The supplied throttle pushrod assembly consists of a wire
pushrod running inside a nylon pushrod tube. On the threaded
end of the pushrod you will have a Metal RC Clevis. For a typical
2-stroke installation we prefer to connect this end of the pushrod
to the throttle servo arm. The plain end of the pushrod wire will
connect to the carburetor using a Metal Pushrod Keeper, which
allows you to easily adjust the overall length of the pushrod at the
carburetor.
c) Install the Metal Pushrod Keeper in the engine's carburetor
control arm, with one hex nut on each side of the arm. Note: You
will probably need to drill out the hole in the carb arm with a 5/64"
dia. (or #47) drill bit to accept the threaded portion of the Pushrod
Keeper. Tighten the hex nuts securely against each side of the
carburetor arm. Be sure to put a small drop of thread locker on
the last hex nut. After the hex nuts are tightened against the arm,
the barrel of the Pushrod Keeper should still be free to rotate.
d) Slide the plain end of the wire pushrod into the airplane from
the back, steering it under the leading edge former, then through
the slotted hole in the firewall.
e) Next slide the Nylon Throttle Pushrod Tube over the plain
end of the pushrod wire at the engine. Keep sliding the tube back
over the pushrod wire, through the hole in the firewall, and keep
sliding it back until approximately 1/2" of the nylon tube remains
in front of the firewall.
f) Now slip the plain end of the pushrod wire inside the pushrod
keeper. Clip the metal RC clevis onto the servo arm and set the
servo in the middle of its travel. Set the carb in the middle of its
travel, and then tighten the set screw in the end of the pushrod
keeper.
g) Turn on your radio and check the operation of the throttle
pushrod. Make adjustments as needed to get full range of carbu-
retor travel. You can adjust the overall length of the pushrod with
the RC Clevis or with the Pushrod Keeper. Use the EPA (End
Point Adjustment) feature of your transmitter to accurately dial-in
the desired amount of servo travel. Also make sure there is no
binding in the throttle linkage, which could cause unnecessary
battery drain.
h) When satisfied with the installation, glue the nylon pushrod
tube permanently to the firewall with epoxy or silicone sealer.
Note: You may find it necessary to support the servo end of the
nylon pushrod tube with a scrap of balsa, plywood, or foam - to
keep the pushrod from flexing.
i) Ideally, this is the range of throttle moment you want to
achieve:
❑
46) 4-STROKE THROTTLE PUSHROD
4-Stroke glow engines typically have their carburetor on the back
of the engine. This puts the throttle arm very close to the firewall
of the airplane. They also often have the carb arm on the left side
of the airplane, instead of on the right like most 2-stokes. Note
that the location for the throttle servo in the plywood tray is on the
right side of the airplane. If you plan to use a 4-stroke engine, it
may be necessary to relocate the throttle servo and the supplied
rigid wire throttle pushrod over to the left side of the airplane. Or
you can leave the throttle servo on the right and use an after-mar-
ket flexible cable type pushrod (not supplied) to get to the left side
of the 4-stroke engine.
❑
47) COWLING
An opening needs to be made in the top of the cowling to clear
the engine cylinder head and carburetor. Don't be tempted to
quickly dive in with a knife and start removing large chunks of ma-
terial. You will achieve a lot better result if you take the time to de-
STICK FORWARD
TRIM FORWARD
HIGH SPEED
STICK BACK
TRIM FORWARD
GOOD IDLE
STICK BACK
TRIM BACK
KILL ENGINE