.
59.
a. Bolt the spinner backplate to the motor. (This must be done to allow for
differences in spinners. For example, the Goldberg spinner has a
recessed backplate which requires the motor to be farther forward than a
spinner without a recess. This is a good thing, giving more clearance
behind the motor for fuel lines or pumps, and is one reason other than the
pleasing shape - that we recommend the Goldberg for the King Kobra.
b. Position the motor on the mounts so the spinner backplate will be 4-7/32"
from the face of the firewall (or in this case, the face of the scrap back). It
is handy to tack the motor in position with some spots of epoxy, brought
up over the edge of engine to grip it good or put a strip of double-faced
masking tape between the engine and the mounts. This will keep it from
slipping during the next step.
60.
With a punch or sharpened piece of 1/8" wire, center punch the motor mounting holes. (Hint: If you are not used to doing
this sort of job, don't try to punch and drill all 4 holes at once. Punch and drill only one hole. Then put the motor back on the
mounts, secured by the first bolt. Punch and drill a 2nd hole, repeat the procedure, then a third hole, etc. With this process
you are much less likely to make a drilling mistake that will ruin the mounts.) Drilling our mounts will not be a problem if a
good quality highspeed drill bit is used, operated at neither too fast nor too slow a speed, lubricated and with moderate
pressure.
Remove the scrap back from the engine mounts.
61.
a. Position the nose gear bearing on the face of the firewall and drill out the holes with a 7/64" bit to pass the bolts.
b. Turn the firewall over and drill out the backs of the 7/64" nosegear bearing holes with a 9/64" bit to take the shanks
of the 4-40 blind nuts. To complete the holes, take a modeling knife and round off the edges on the back of the
firewall so that the rounded off part of the blind nut will fit down into the hole when it is pulled tight against the
firewall.
Fit the cowl to the firewall next, before the engine mounts are permanently fastened to the firewall. This allows checking
out the placement of the mounts in relation to the cowling. Take the carburetor off the engine and tape over the hole.
Having it out of the way makes it easier to make the openings with proper fit.
62.
a. Start the opening with a saw.
b. The curved part is done by drilling a series of holes about 1/8" in diameter around the area to be removed, then
cutting through the bits of plastic between with a knife.
63.
Try for a slightly undersized opening at
first, then open it up slowly as you fit it to
the engine. Go around the edge with an
"apple peeling" motion, paring off a small
amount of plastic at a time. Remember,
it's easier to take off a dozen more chips
than it is to put one back on.
64.
Sit the mounted engine in place. Put the cowl over it and add the spinner backplate. If the backplate is not centered on the
cowl, shift the engine-mount unit as required to make the spinner center. Carefully remove the cowl and tack glue the
engine mount in place. (We tack glue it partially so it won't move before removing the cowl. Drill through the mounting
holes and install 6-32 blind nuts on the back of the firewall.