Yanmar 4TNE98, Service Manual

Page: 126 / 246

4TNV98 & 4TNE98 Diesel Engine Section 3. Engine 124
Inspection of Connecting Rod
1. Measure the wrist pin bushing bore using a bore
gauge (Figure 6-116, (1)) . Replace the bushing if
not within specifications. If the bushing has been
removed, measure the inside diameter of the
connecting rod small end
(Figure 6-116, (2)) . See
Connecting Rod on page 72 for specifications.
Figure 6-116
2. Place the connecting rod bearing inserts into the
connecting rod and connecting rod cap. Install the
rod cap and tighten the bolts to the specified
torque.
3. Measure the inside diameter. See Crankshaft on
page 70 for specifications.
Inspection of Tappets
1. Inspect the tappet contact surfaces for abnormal
wear (Figure 6-117, (1)) . Normal wear will be
even as shown in (Figure 6-117, (2)) . Slight
surface defects can be corrected using an oilstone.
Figure 6-117
2. Measure the outside diameter of the tappet stem
(Figure 6-118, (1)) . See Tappet on page 72 for the
service limit.
Figure 6-118
3. Measure the tappet bores in the cylinder block.
See Tappet on page 72 for the service limit.
Inspection of Crankshaft
1. Place the crankshaft end journals
(Figure 6-119, (4)) on V-blocks.
2. Place a dial indicator (Figure 6-119, (3)) on a
center main bearing surface.
Figure 6-119
3. Rotate the crankshaft and observe runout. See
Crankshaft on page 70 for specifications.