Shibaura N843 - Cam Shaft Assembly; Timing Gear

3-12 109823 2/09
Inspection
Check the ring gear and replace if damaged or excessive
wear is noticed.
When the wear is limited to a small area, remove the, ring
gear, turn it about 90 degrees and shrinkage-fit to reuse it.
To shrinkage-fit the ring gear, heat it to 248-302°F(120–
150°C) to allow it to expand.
Cam shaft assembly
Inspection
1. Check the journal and cam for wear and damage
and replace if the service limit is exceeded.
2. Correct insignificant uneven wear or scars on the
cam surface using oil stone or equivalent.
Timing gear
Inspection
1. If pitting or excessive wear is observed on the tooth
face of gears, replace the gear.
2. Measure the backlash of gears and replace if the
service limit is exceeded.
A. Height of intake/exhaust valve cams in(mm)
Standard assembling
value
Service limit
1.0459-1.0480
(26.565-26.62)
Less than 1.032(26.2)
B. Height of injection pump cams in(mm)
Standard assembling
value
Service limit
1.5701-1.5764
(39.88-40.04)
Less than 1.563(39.7)
Timing gear backlash in(mm)
Standard assembling
value
Service limit
0.0031(0.08) More than 0.0098(0.25)
Fig. 3-30
Fig. 3-31
Fig. 3-32
Fig. 3-33
A
B
A
B
Cam shaft gear
Idler gear
Crankshaft gear
Match mark
Match mark