Great Planes Super Sportster 90/120 Kit - GPMA0214 - Manual (Page 23)

D Ib. If you are using the hardwood engine
mounting rails supplied in this kit, set your
engine in place on the rails to check the fit. If
the space between the rails is too narrow, file
or sand the rails until the engine fits properly.
If you are installing a .60 engine that requires
a smaller opening between the rails, epoxy 1/8"
strips of hardwood or ply to the inside of the
rails as shown in the following sketch. Position
the engine fore-and-aft so the front of the
"thrust washer" (rear of spinner backplate) is
3/4" (or slightly less) forward of the front edge
of the mounting rails. Note: This puts the
thrust washer of the OS Max .91 FSR approx-
imately 5-1/8" forward of F-l, and the thrust
washer of the OS Max FS-120 approximately
5-1/2" forward of F-l.
MOUNTING RAIL
MODIFICATION
FOR SMALLER ENGINES
Epoxy 1/8" ply or hardwood
strips lo inside of rails
. Use 6-32 blind nufs -
and mounting hardware
(Not supplied)
D 3. Drill holes in the hardwood rails for the 10-32
blind nuts. To maintain accurate positioning
of these holes and to minimize splitting the
wood, we recommend that you begin by drilling
3/32" diameter pilot holes, then use progres-
sively larger drill bits until the holes are large
enough to accept the blind nuts.
D 4. Install the blind nuts in the bottom of the
hardwood rails. Note that part of the blind nut
flanges protrude into the engine mounting
area. Trial fit your engine to find out if the
protruding portion of the blind nuts will inter-
fere with the engine crankcase. If they do, use
a hacksaw or a Dremel Moto Tool and a "Tuff
Grind" wheel to remove any part of the blind
nuts that would touch the engine.
D 5. Temporarily mount your engine.
INSTALL NOSE GEAR (If applicable)
D 1. Using a long 5/32" drill bit, drill down
through the nylon nose gear bearing and
through the chin block.
2. Insert the nose gear until the spring rests
on the bottom of the chin block. Rotate the nose
gear (simulating a right and left turn) and
mark the location of the spring on the chin
block in all positions.
D 3. Using a Dremel Moto Tool, rout out an area
in the chin block for the nose gear spring.
D 2. With the engine located as described above,
centered between the rails, and aligned for zero
degrees side thrust, mark the mounting hole
locations.
NOTE: In this kit we have provided 10-32 bolts and
blind nuts which are the proper size for mounting
the OS Max .91 FSR or the OS Max FS-120. If, how-
ever, you are using an engine which requires
6-32 or 8-32 mounting hardware, please adjust
the hole sizes in the following step to accommo-
date the hardware you are using.
4. Re-insert the nose gear and check for un-
obstructed movement.
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