two paper gaskets (18) against mounting
seated in recess in cylinder head. Hold
flange of first stage cylinder.
components in position with fingers.
(6) With assembled components held in
Note. The total thickness of new
place, assemble parts (10) through
gaskets used with the cylinder during
(12) on screw (14) and insert screw
reassembly should agree with the
with parts assembled through spring
measurements
taken
from
the
(8), valve (9), and hole in cylinder
original gaskets during disassembly
head.
plus allowance for new gasket crush.
(7) Use a 1/8-inch rod inserted through an
inner hole of plate (10) to apply
(2) Install first stage piston of cylinder-and-
pressure against valve (9).
piston assembly (20) to master rod by
(8) With pressure applied against the
pressing wrist-pin (16) through piston
valve (9) by rod, slide plate (10) into
and master rod. Secure wrist-pin by
cylinder head (5) until seated.
installing rings (17).
(9) Apply finger pressure against screw
(14) and remove 1/8-inch rod.
Note.
Be certain that the mark
(10) With finger pressure still applied, invert
scribed inside piston skirts during
cylinder head (5) and secure screw
disassembly faces fan end of
(14) with washer (4) and nut (1).
crankcase.
(11) Install packing (13) on outer edge of
cylinder head (5). Place the cylinder
(3) Place endbell on crankcase. Refer to
head on the cylinder making certain
paragraph 3-15d(8) for alignment of
fins on the cylinder and cylinder head
the crankshaft. Slip first stage cylinder
are slanted in same direction. Secure
of cylinder-and-piston assembly (20)
the cylinder head to the cylinder with
over installed piston and over four
four screws (2) and washers (3).
studs of crankcase mounting hole.
(12) Replace breather assembly on top
Install four nuts (15) and tighten
cylinder head (para 3-11c) (fig. 3-3).
evenly. (Cylinder should be installed
with leading edge of cooling fins
3-13. Second Stage Section
slanted toward fan end of shaft.)
(4) Use a depth micrometer or dial
a. Description. The second stage section
indicator to measure piston-head-to-
consists of a strainer-and-relief valve assembly,
valve-seat clearance.
Required
connecting link, bearings, wrist-pins, exhaust valve
clearance is 0.021 to 0.026 inch. Add
spring, exhaust valve, cylinder-and-piston assembly,
or remove gaskets (18 and 19) as
rupture disk assembly, and attaching hardware.
necessary to shim cylinder.
b. Maintenance. Overhaul of the second stage
Note.
Overall thickness of steel
section (fig. 3-5) is accomplished by replacing the
gaskets
can
be
reduced
in
second stage cylinder cap, exhaust valve spring, exhaust
increments of 0.002 inch by peeling
valve, gaskets, connecting link, the cylinder-and-piston
off laminations. At least one paper
assembly, and attaching parts.
gasket must remain on each side of
steel gasket in final installation. To
measure and adjust piston-to-valve-
seat clearance, install one cylinder-
and-piston assembly to guide the
cylinder
being
measured
and
adjusted.
(5) Invert cylinder head (5). Insert valve
stop (7) in cylinder head.
Place
spring (8) in valve stop. Install packing
(6) in groove in cylinder head. Place
valve (9) on spring (8) and depress
with the fingers until valve is
21