Top Flite TOPA0155 - Manual (Page 51)

Mount the engine
Refer to this photo to mount the engine.
❏
1. Mount the engine mount to the firewall with four
8-32 x 1" [25.4mm] socket-head cap screws and four
#8 lock washers and flat washers. Do not tighten the
screws all the way. Fit the engine to the mount.
Adjust the spacing of the engine mount halves to
accommodate the engine and tighten the screws.
❏
2. Fit the back plate of the spinner on the engine.
Use small clamps to temporarily hold the engine to
the mount so the back plate of the spinner is 5-3/4"
[146mm] from the firewall.
❏
3. Use a Great Planes Dead Center ™ engine
mount hole locator (GPMR8139) or your own
method to mark the location of the engine mounting
bolt holes on the engine mount.
❏
4. Remove the engine from the mount. Drill #29
holes at the marks and use an 8-32 tap to tap
threads into the holes.
❏
5. Mount the engine to the mount with four 8-32 x 1"
[25.4mm] socket-head cap screws and #8 lock washers.
Mount the cowl
1. Cut six 1" [25mm] long cowl mounting blocks
from the 5/8" x 5/8" x 9" [15.9 x 15.9 x 229mm]
basswood stick. Hold one of the blocks to the fuse
against former F2, so one edge is just above the
fuse sheeting. Use a ballpoint pen to draw the outline
of the fuse onto the block. Sand the block to match
the line. Mark and round the rest of the cowl
mounting blocks the same way. (The cowl mounting
blocks and muffler can be seen in following photos.)
❏
2. Glue the cowl mounting blocks to the fuse with
the outer edges inset approximately 3/32" [2.4mm]
below the fuse sheeting to accommodate the cowl. If
using a two-stroke engine with a Top Flite In-Cowl
muffler, test fit the muffler and position the bottom,
center cowl mounting block so it will not interfere with
the muffler.
❏
3. Position the cowl on the fuse. Mark the center
of the cowl mounting blocks onto the cowl. Use
epoxy to glue the six die-cut 1/32" [.8mm] plywood
cowl reinforcements inside the cowl centered on
the marks.
❏
4. Reposition the cowl on the fuse. Place the back
plate of the spinner on the engine. Viewing the model
from the front center the cowl on the back plate. Note
where the aft edge of the cowl requires trimming for
a good fit to the fuse. Hint: roughen the aft inch or so
of the outside of the cowl with medium-grit
sandpaper. Use a pencil to mark the “high spots” on
the cowl where trimming is required.
❏
5. Use a bar sander with 80-grit sandpaper to trim
the aft edge of the cowl where required. Reposition
the cowl on the fuse and mark and trim as necessary
until a good fit is achieved.
❏
6. Securely tape the cowl to the fuse. Drill a 1/16"
[1.6mm] hole through the cowl into one of the cowl
mounting blocks 7/16" [11mm] from the aft edge of the
cowl. Use a Dremel #178 cutting bit or something
similar to enlarge the opening of the hole for the head of
a #2 x 3/8" [9.5mm] flat head screw. Install the screw.
-51-