Building The Ox-5 Engine - Model Airways CURTISS JN-4D JENNY Instruction Manual

The fuel tank is supported by two brass
straps, one end hanging off the rear ends of
the engine bearers and the other ends hang-
ing on the top horizontal strut at Station 4.
This is just one method of supporting the
tank. Other arrangements have been found
in photos of the real aircraft. Place the tank
onto the support straps.
In the right and left top longerons at the
center of the tank, insert a single eye rig fit-
ting (R1). Drill a hole in each end of a hold-
down strap made from brass strip. Bend and
fit over the tank, then use gray rigging cord
to tie the strap down to the single eye fit-
tings. .
(Figure 5-2)
Make sure the fuel tank is correctly
Caution:
located according to plan. If it is too far for-
ward it will hit the water pump at the rear
end of the engine.

2. Building the OX-5 Engine

Sheet 5 illustrates various views of the
assembled engine at model scale. The sheet
also shows some enlarged details for assem-
bling the basic castings. These views are
helpful, as the engine to scale has some very
small detail.
In addition to holes you need to drill your-
self, there are a number of precast holes.
There is a possibility some of these holes
may not cast well because of the small size.
Ream the holes out with a drill bit and test
fit the parts in the holes to make sure the
assembly can be accomplished. Clean off any
remaining flash on the castings.
Engine block assembly:
Before assembling
the upper and lower engine blocks (E15A &
E16), locate, mark, and drill a hole in front
of the upper block for the oil tube from the
oil pump. On the lower engine block, drill
the two holes in the back of the block for the
V intake manifold (E39). The plans indicate
the location of the holes relative to the top
of the lower engine block.
Glue the six engine bolting feet (E15B) into
the bottom slots of the upper engine block
(E15A). Make sure the feet are flush on the
bottom. If necessary, file them flush so the
entire bottom of the block is flat. On the
real engine, these are a part of the upper
block casting, but for the model they have
been cast separately. Then, glue the upper
engine block assembly to the lower block.
Make sure the semicircular holes at the
front of the blocks are aligned, and that the
side flanges of the lower block are flush
with the flat sides of the upper block
.
(Figure 5-3)
Glue the rear oil fill fitting (E20) into the
upper engine block hole on the right side of
the block. Clean the precast hole if necessary.
Glue the double bracket fitting (E21) on top
of the prop shaft housing (E17A). Glue the
oil fill (E20) into the hole at the center of
E21. You may need to shorten E20 a bit or
drill the hole deeper into E17A.
Glue the prop shaft housing assembly into
the front hole in the assembled engine
UPPER BLOCK E15A
DRILL HOLE
FOR
OIL TUBE
FIG. 5-4 FRONT HOUSINGS, OIL FILLS & SUMP COVER
OIL FILL
E20
(THIS SIDE
ONLY)
PRECAST HOLE IN
BOTTOM OF BLOCK
SUMP COVER E22
DRILL HOLES IN FITTINGS
FOR COPPER WIRE
TO COCKPIT GAUGES (SEE FIG. 5-16)
block. Make sure it is aligned evenly. Glue
the oil pump and housing (E17B) to the
front of the lower engine block and bottom
of E17A. The fitting should be vertical, as
shown on the plan. There are no alignment
pins for this fitting. Glue should suffice, but
you could add a pin if you so desire.
Install the sump cover (E22) in the precast
hole in the bottom of the lower engine
block. Clean out the hole if necessary.
Using copper wire to represent tubing, add
wire between the oil pump and top front of
the engine block (hole you drilled), and
from the oil pump to the sump cover.
There is also a wire from the oil pump to
the cockpit gauges. This will be discussed
and installed later during this Stage
. Drill holes as necessary in
Paragraph 5)
the fittings for inserting the wire.
illustrates the addition of the front
5-4
housings, oil fills, sump cover, and associ-
ated tubing runs.
25
FIG. 5-3 BLOCK ASSEMBLY
LOWER BLOCK E16
RUN OF COPPER WIRE
OIL TUBING
The prop shaft housing includes the
Note:
prop shaft molded into one casting. On the
real engine the housing is really a part of the
engine block. Likewise, the oil pump hous-
ing is a part of the lower engine block.
Carburetor/V intake manifold support,
V intake manifold, and carburetor
(Figure 5-5):
manifold support (E23) into the two holes in
the bottom of the lower engine block. This
fitting supports both the carburetor and the
V intake manifold. If necessary, bend both
ends of the support so that the front end and
aft end are parallel. This fitting is not quite
horizontal from bottom of the engine block
to bottom of the V intake manifold.
Drill holes into the sides of the V intake
(see
manifold (E39) that will take wire (water
tubing) later. Then, install the V intake
Figure
manifold. Insert the bottom pin through
the hole in the carburetor support plate,
and glue the upper pins into the holes that
BOLTING FEET E15B
(6 TOTAL)
DRILL HOLES
FOR V INTAKE
MANIFOLD E39
BACK END OF BLOCK
OIL FILL E20
DOUBLE
BRACKET
E21
PROP SHAFT
HOUSING E17A
OIL PUMP E17B
Glue the carburetor/V intake