Yanmar 4TNV98, Service Manual

Page: 121 / 246

4TNV98 & 4TNE98 Diesel Engine Section 3. Engine 119
• Method B : Use a feeler gauge to measure the
clearance (Figure 6-103, (3)) between the thrust
bearing (Figure 6-103, (1)) and crankshaft
(Figure 6-103, (2)) . Record the measurement.
See Thrust Bearing on page 70 for the service
limit.
Figure 6-103
4. Remove the main bearing caps
(Figure 6-104, (3)) . Be sure to note the markings
on the main bearing caps, or mark them yourself,
so they can be reinstalled in the same order as
they were removed. Do not remove the bearing
inserts at this time.
NOTE : The “arrows” on the main bearing caps point
to the flywheel end of the engine.
Figure 6-104
5. Measure bearing oil clearance prior to removing
the crankshaft to determine extent of wear.
Record the measurements.
(a) Wipe oil from the bearing insert and crankshaft
journal surfaces.
(b) Place a piece of PLASTIGAGE
(Figure 6-105, (1)) along the full width of each
bearing insert.