TM 5-6115-405-15
c. Install thrust bearing (26) and bearing race (25)
k. Using a pair of retaining ring pliers, install new
retaining ring (17) into the groove in piston (20) with the
on each end of crankshaft (27). Install loading spring
(24) on the generator end of the crankshaft with the
square edge of the ring facing outward. Rotate the ring
open feet of the spring inward.
to be sure it is installed properly, and align
the
open end parallel with the connecting rod (either up or
d. Making sure woodruff key (21) is not in place,
down).
install fabricated seal assembling sleeve with beveled
l. Using bearing grease or beeswax to lay out new
end out onto the key end of crankshaft (27). Lubricate
the sleeve and end of the crankshaft to prevent
needle rollers, lay out one strip of 16 rollers and one of
damage.
15 rollers.
Insert one strip of rollers into each
connecting rod half.
e. Carefully insert crankshaft (27) into crankcase
m. Bend a strip of metal or wire to hold the lower
(29). Remove seal assembling sleeve and install it on
the opposite end of the crankshaft. Lubricate the sleeve
half of connecting rod (15) in position under the shaft
journal. Make sure piston pin retaining ring is toward the
and shaft as in step d. Install woodruff key (21) in
keyway of crankshaft (27).
magneto end of the engine. Align the match marks on
connecting rod halves. Position the upper half of
f. Place crankcase gasket (35, fig. 6-2) carefully
connecting rod and secure with new socket head screws
in position and secure drivecase (75) to crankcase (29,
(13). Tighten screws to a torque of 55 to 61 pound-
inches. Rotate shaft to check that all needle rollers are
6-2). Note that the length of these screws is critical. Be
in position and the bearing turns smoothly.
sure proper screws are used.
n. Position cylinder gasket (11) in place so that
g. Remove fabricated seal assembling sleeve.
holes are alined.
h. Using fabricated needle bearing assembling tool
o. Apply some oil to piston (20) and interior of
and pressing only on the lettered side of needle bearing
cylinder (10).
If a piston ring compressor is not
(16, fig. 6-4), install bearing in connecting rod.(15).
available, use a strip of metal bent to 1 3/8-inch
i. Carefully install piston ring set (19) on piston
diameter to compress the piston rings and install
(20) with the open ends adjacent to the piston ring
cylinder (10) straight down over the piston with the
retaining pin.
j. Insert connecting rod (15) into piston (20). Use
compressor strip and secure cylinder to crankcase
a 3/16-inch diameter rod to press on the open end of
studs, with nuts (8) and lockwashers (9). Use fabricated
piston pin (18) and press the pin into the piston.
offset wrench to tighten nuts.
Section V. CARBURETOR ASSEMBLY
6-17. General
c. Inspect fuel pump diaphragm (5) and diaphragm
This section contains complete repair instructions for the
(10) for breaks or punctures. Replace if damaged.
carburetor assembly.
d. In extreme cases of clogged channels -and
discharge ports, it may be necessary to remove
6-18. Disassembly
expansion plug (16). If required, drill a 1/16-inch hole
Figure 6-5 is a complete exploded view of the carburetor
through the plug just deep enough to break through the
assembly. Disassemble in the numerical sequence
plug. Carefully pry out the plug and discard. Clean
indicated on figure 6-5.
channels and discharge ports. Install a new plug by
placing the plug in well, convex side up, and flatten with
6-19. Inspection and Repair
a tool slightly larger than the plug.
a. To clean carburetor parts, use approved
solvents except an diaphragms and gaskets.
b. Blow out channels in body (30, fig. 6-5) with
compressed air.
6-13
