Top Flite TOPA0906 - Manual (Page 21)

21
holes. Attach the engine to the mount using four
8-32 x 1" [25mm] SHCS, four #8 flat washers, and
four #8 lock washers.
o 7. Install the throttle servo in the location shown.
Because of the tight working space here, a Hobbico
Pin Vise (HCAR0696) is very useful in this step. Use
the hardware included with the servo.
o 8. Drill a 3/16" [4.8mm] hole in the firewall inline
with the throttle arm on the carburetor at a slight angle
pointing to the throttle servo. We used an extra long
drill bit (HIGR1020). If you do not have an extra long
bit, you may need to mark the location for the hole
on the firewall and temporarily remove the engine to
drill the hole.
Make sure you do not drill into the
fuel tank!
o 9. Cut three arms from a four-armed servo arm. Install
a brass screw-lock pushrod connector into the second
outer hole of the remaining arm using a nylon retainer.
Loosely thread a 4-40 x 1/8" [3mm] SHCS into the screw-
lock pushrod connector. Use your radio system to center
the throttle servo and attach the arm perpendicular to the
servo case pointing to the center of the fuselage. Be sure
to install the servo arm screw. Thread a nylon clevis and
silicone clevis retainer onto a 12" [305mm] pushrod. Fit
the pushrod through the hole you drilled in the firewall and
connect the clevis to the throttle arm on the carburetor. The
other end should pass through the screw-lock pushrod
connector. Make any necessary bends to the pushrod so
it moves smoothly through the hole and does not contact
the engine crankcase during any point in its travel. Operate
the throttle servo with your radio system to confirm
the servo properly opens and closes the carb. When
satisfied, tighten the SHCS in the screw-lock pushrod
connector against the pushrod, cut off the excess pushrod
3/8" [9.5mm] beyond the connector, and slide the silicone
clevis retainer to the end of the clevis.
o 10. Install a Pitts-style muffler onto the engine. Cut
the vent line and carb lines to the appropriate length
and connect them to the engine and muffler. Use the
included fuel line plug for the fill line. Parts are included
for an optional fill line clip that can be glued to the
bottom of the first former as shown. Glue the parts
together and fuelproof the assembly with epoxy.