F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
5 - M
AINTENANCE
PAGE 5-7
while supporting the connection rod so that it does not drop.
5.
Turn the crankshaft until the throw is near to its highest point position. Com-
pletely loosen the connecting-rod-cap bolting and remove the top two cap-
screws.
6.
F
IGURE
5-5 R
OD
AND
R
OD
C
AP
S
EPARATION
Connecting
Rod Cap
Gently Tap Here when
Separating Cap
Rod-Cap
Cap-Screws (4)
Conn
ectin
g
Rod
Separate the rod cap
from the rod. Use the
bottom two rod-cap
cap-screws as a han-
dles to pull on the bot-
tom of the rod cap
while tapping the top
face of the rod cap
with a semi-soft faced
hammer. Do not pull
or strike the rod cap
too hard; it may break
the rod cap dowels.
Work the rod cap
away from rod as
evenly as possible.
Separating the two
parts unevenly may
break the rod cap
dowels or cause them
to bind in the rod dowel holes. See Figure above.
7.
Remove the rod cap and its bearing half shell.
8.
The bearing shell may fall out when separating the connecting rod and cap from
the crankshaft pin. If bearing shells do not come loose, rotate/slide them out of
the connecting rod and/or cap.
9.
Turn the crankshaft throw to near the inner dead center position and remove the
rod through the crosshead guide opening (or connecting rod access hole on the
JGI).
10. After the removal of the connecting rods, be sure to protect the crank pins from
being nicked or scratched.
NOTE: IF ALL CONNECTING RODS ARE TO BE REMOVED, IT MAY BE MORE EXPE-
DIENT TO REMOVE THE CRANKSHAFT PRIOR TO REMOVING THE RODS.
Connecting Rod Bushing Replacement
1.
Check crosshead pin to connecting rod bushing clearance (see Table 1-3 on
page 1-10 for recommended clearance.) Inspect the pin for wear and replace it if
necessary.
2.
To replace a rod bushing file or hack saw the existing bushing to reduce the
tightness of the shrink fit. From the inside diameter file or saw across the length
of the bushing to within 1/32 inch (1 mm) of its radial thickness. It can then be
easily drifted out. Be careful, not to file or saw into the connecting rod,
as any
rod bore damage makes the rod unusable
.
3.
Use a hydraulic press in a qualified machine shop to install the new bushing. Do
not hammer the bushing into place as this distorts the bushing bore. Before
