❑
40) The first step is to mount your throttle servo in the fuselage,
using the rubber grommets, eyelets, and screws that came with
the servo. Put the control arm end of the servo on the same side
of the fuselage as you engine’s carburetor control arm.
❑
41) Determine the exact route your pushrod will take between
the throttle servo and the engine throttle arm. In most cases you
will want the pushrod to run right alongside the engine mount and
fuel tank, and then angle over to the throttle servo arm. After de-
termining the proper location, drill a 3/16" diameter hole through
the firewall for the throttle pushrod to pass through.
❑
42) A nylon pushrod tube is supplied to make an outer sleeve
for the throttle pushrod wire to ride in. The nylon tube is extra long
so it can be adapted to many variations in equipment. Determine
how long it should be for your installation. For a typical 2-stroke
setup you will want about 1” of tube sticking out in front of the fire-
wall, and the other end of the tube to stop about 1” away from the
throttle servo. Mark and cut off the tube to the appropriate length,
and then install it in the airplane, gluing it securely to the firewall.
❑
43) Install the metal pushrod connector in the engine throttle
arm, with one hex nut on each sice of the arm. You will need to
drill out the hole in the arm with a 5/64" dia. (or #47) drill bit to ac-
cept the threaded portion of the pushrod connector. Tighten the
two hex nuts of the pushrod connector securely against the throt-
tle arm. If you take the set screw temporarily out of the pushrod
connector, you can use a small screwdriver to go down through
the connector body to hold the head of the bolt, which makes it
much easier to tighten the hex nuts.
❑
44) Install the throttle pushrod wire.
a) Slide the plain end of the wire into the plastic sleeve from
the servo end. Keep sliding it forward until it emerges from the
front of the sleeve. Guide the end of the wire into the pushrod
connector on the engine. Do not tighten the set screw at this time.
b) Remove the arm from the throttle servo and install it on the
Z-bend of the pushrod wire. Then re-install the arm on the servo.
c) Test the operation of the throttle pushrod. Adjust the length
of the throttle pushrod using the pushrod connector at the carbu-
retor. Adjust the overall travel of the pushrod using the transmit-
ter's "End Point Adjustment".
d) Use the supplied small balsa block to make a support for
the servo end of the outer plastic pushrod sleeve. Trim the block
to fit between the sleeve and the fuselage side. Glue the block to
both the sleeve and pushrod side.
THROTTLE PUSHROD FOR 4-STROKE ENGINES
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, makng the hookup of this end of the throttle
pushrod more difficult. If you are using a 4-stroke engine you
should take a look at some of the special after-market fittings that
are available for this type of installation. For instance Du-Bro®
makes a 4-stroke throttle linkage for the carb end of the pushrod,
that will work well in conjunction with the wire pushrod parts in-
cluded in this kit.
FUEL TANK
❑
45) Assemble the Fuel Tank.
a) Locate the Rubber Stopper Assembly. There are three nylon
tubes going through the rubber stopper. Orient the stopper so
that one of the tubes is towards the top and then bend that tube
up at a 45-degree angle. Do not apply heat to the tube - it will
bend without heat. Just overbend it to nearly 90-degrees and then
let it relax, to see where it will end up. Repeat if necessary until
the tube will stay at 45-degrees.
b) Attach the metal Fuel Pick-Up Weight on one end of the sil-
icone Fuel Line Tubing that goes inside the tank. Cut the other
end of the fuel line tubing to a length that will allow the clunk to
reach the back of the tank, without getting stuck on the walls of
the tank. Test fit in the tank and adjust as necessary. With the
stopper assembly in place, the fuel clunk should sit just in front of
the rear of the tank and move freely inside the tank. If not pull the
assembly back out and trim the tubing back until the stopper
moves freely. The top of the vent tube should rest just below the
top of the tank. It should not touch the top of the tank.
c) Once you are satisfied with the fit of both the fuel clunk line
and the vent line you can tighten the machine screw to expand
the rubber stopper and seal the stopper in the tank. Do not over
tighten the screw as it can cause the tank to split. Attach three 6-
inch lengths of silicone fuel tubing (not furnished) to the tank and
label them appropriately as FILL, CARB, and VENT so you can
identify them after the tank is installed in the airplane.
❑
46) Install the fuel tank in the fuselage.
a) Slip the fuel tank in place, poking the neck of the tank into
the plywood front support.
b) Test fit the plywood rear fuel tank mount at the back of the
tank, right up against the back side of the front fuselage former.
You will have to notch one side to clear the throttle pushrod. Then
glue the plywood rear mount permanently to the back of the fuse-
lage former.
c) Use common silicone bathtub sealer (not furnished) to glue
the fuel tank to the front and rear plywood tank mounts.
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