NOTE
The piston and pin (1) are matched and
are not to be replaced separately.
Replace as an assembly only. The
compression rings (3) and oil control ring
(4) are supplied in the form of a piston
ring kit and should be replaced only as a
kit set.
(2)
Remove eight cap screws (6) and lock
washers (7); remove cylinder head (5),
head gasket (8), valve assembly (9) and
valve gasket (16) from cylinder (I 7).
(3)
To disassemble valve assembly (9),
remove cotter pin (11) and castle nut;
separate upper plate from lower plate.
NOTE
The valve ring (14), lentoid springs (12),
valve ring (13), lentoid springs (15), and
cotter pin (11) are’ supplied in the form
of a valve repair kit and shall be
replaced as such.
(4)
Remove valve ring (14), lentoid springs
(12), valve ring (13), and lentoid springs
(15).
(5)
The center bolt is secured in lower plate
with dowel pin peened over and neither
should be removed.
b.
Cleaning. Refer to paragraph 6-3.a for general
cleaning instructions.
(1)
Remove caked grease or dirt with a
nonmetallic brush after immersing part in
solvent. Scrape carbon, grease, and old
gasket material from affected surfaces.
(2)
Clean parts with care. Do not mar or
scratch contact or seating surfaces. Valve
components should not be wire brushed.
c.
Inspection. Refer to paragraph 6-3.b for general
inspection instructions.
(1)
Parts with dimensions listed in Table 6-1,
Table of Limits, shall be measured to
ascertain acceptability for repair or
replacement and assembly.
d.
Repair or Replacement. Refer to paragraph 6-
3.c for general repair or replacement instructions.
(1)
Replace all gaskets removed during
disassembly.
Do not remove any more material than is
necessary to completely remove the
glaze. Clean the cylinders in
accordance with CLEANING
procedures.
(2)
Remove glaze from cylinder walls with
portable cylinder hone (using 280 to 400
grit stones), a glaze or a crocus cloth,
depending on condition of cylinder walls.
e.
Assembly. To assemble the second stage
cylinder and piston group, proceed as follows:
NOTE
A repair kit consisting of valve ring (14),
lentoid springs (12), valve ring (13),
lentoid springs (15), and cotter pin (11)
is available. At overhaul replace these
parts as a set. Assemble lentoid springs
(12 and 15) as shown in Figure 6-8.
(1)
At overhaul of intake-exhaust valve
assembly (9, Figure 8-15) use available
repair kit. Assemble lentoid springs (15),
valve ring (13), lentoid springs (12), valve
ring (14) and upper plate attach with nut
and secure the nut in place on center bolt
with cotter pin (11).
(2)
Assemble valve gasket (16), intake-
exhaust valve assembly (9), head gasket
(8), and cylinder head (5). Secure head
with eight lock washers (7) and eight 1-1/4
inch long cap screws (6). See Table 6-2
for torque values.
6-19.
Third Stage Cylinder and Piston Group. (See
Figure 8-16). The following paragraphs contain
disassembly, cleaning, inspection, repair or replacement,
and assembly instructions for the third stage cylinder and
piston group.
a.
Disassembly. Disassemble the third stage
cylinder and piston group only to the extent necessary to
repair or replace a defective part or parts.
(1)
Remove ’the piston and pin assembly (I)
with piston rings (2) from cylinder ( 16).
6-26
