Jacobsen SXG323, Service Manual

Page: 56 / 230

CHAPTER 4. ENGINE
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4
oil clearance again. When the clearance exceeds
the usable limit ever after new bearing have been
installed, polish the pin and use undersize bear-
ings.
When the ground-down limit of 1.0 mm (0.039
in.) is enough for correction, replace both crank-
shaft and bearings with new ones.
• Thrust clearance
Install the connecting rod on the crank pin and
measure the thrust play with thickness gauges.
If the play exceeds the usable limit, replace the
connecting rod.
Fig. 4-71
(3) Inspection of the flywheel
Check the friction surface for cracks and other
damage. If defective, correct or replace with a
new flywheel.
Check the ring gear teeth for excessive wear and
other damage. If defective, replace the ring gear
with a new one.
Fig. 4-72
• Replacement of the ring gear
Hammer the circumference of the ring gear
evenly via a holding rod to remove the ring gear.
Fig. 4-73
Heat up a new ring gear with a torch, and then
drive it onto the flywheel.
Fig. 4-74
Note:
- Install the ring gear with the chamfered side
turned toward the starter.
- After installation, make sure the ring gear is in
tight contact with the flywheel.
Undersize bearings 0.5; 1.0 mm
Standard value Usable limit
0.04 - 0.215 mm 0.30 mm