Page 1026 of 6000
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ENGINE MECHANICAL
7. Remove oil gallery (7).
8. Remove piston and connecting rod assembly (8).
Refer to “Piston, Piston Ring and Connecting Rod” in
this manual.
9. Remove flywheel (9).
10. Remove rear oil seal retainer (10).
11. Remove main bearing cap (11).
12. Remove crankshaft (12).
Inspection and Repair
1. Crankshaft
Set the dial indicator as shown in the illustration and
measure the crankshaft thrust clearance. If the thrust
clearance exceeds the specified limit, replace the
thrust bearings as a set.
Thrust Clearance
Standard : 0.06 mm–0.24 mm
(0.0024 in–0.0094 in)
Limit : 0.30 mm (0.0118 in)
015RS003
Main Bearing Clearance
1. Remove the bearing caps and measure the oil
clearance.
2. Remove the main bearing cap fixing bolts in the
sequence shown in the illustration.
Arrange the removed main bearing caps in the
cylinder number order.
Remove the main bearings.
015RS004
3. Remove the crankshaft.
Remove the main bearings.
4. Clean the upper and lower bearings as well as the
crankshaft main journal.
5. Check the bearings for damage or excessive wear.
The bearings must be replaced as a set if damage or
excessive wear is discovered during inspection.
6. Set the upper bearings and the thrust washers to their
original positions.
Carefully install the crankshaft.
7. Set the lower bearings to the bearing cap original
position.
8. Apply plastigage to the crankshaft journal unit as
shown in the illustration.
NOTE: Do not set the plastigage on the oil hole.
015RS005
9. Install main bearing caps, oil gallery and crank case
bolts in the order shown, and tighten each bolt to the
specified torque.
Page 1027 of 6000
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ENGINE MECHANICAL
NOTE: Do not apply engine oil to the crank case side
bolts.
Main bearing cap bolts.
Torque: 39 Nꞏm (4.0 Kgꞏm/29 lb ft)
Oil gallery fixing bolts.
Torque:
1st step: 29 Nꞏm (3.0 Kgꞏm/21 lb ft)
2nd step 55
65
Crank case side bolts
Torque : 39 Nꞏm (4.0 Kgꞏm/29 lb ft)
NOTE: Do not allow the crankshaft to rotate.
015RS006
10. Remove the main bearing caps in the sequence
shown in the illustration.
015RS004
11. Measure the plastigage width and determine the oil
clearance. If the oil clearance exceeds the specified
limit, replace the main bearings as a set and/or
replace the crankshaft.
Standard : 0.019 mm–0.043 mm
(0.0007 in–0.0017 in)Limit : 0.08 mm (0.0031 in)
015RS008
12. Clean the plastigage from the bearings and the
crankshaft.
Remove the crankshaft and the bearings.
Crankshaft (12) Inspection
Inspect the surface of the crankshaft journal and crank
pins for excessive wear and damage. Inspect the oil seal
fitting surfaces for excessive wear and damage. Inspect
the oil ports for obstructions.
Inspection and Repair
1. Carefully set the crankshaft on the V–blocks. Slowly
rotate the crankshaft and measure the runout. If the
crankshaft runout exceeds the specified limit, the
crankshaft must be replaced.
Runout : 0.04 mm (0.0016 in)
015RS007
Page 1029 of 6000
6A–73
ENGINE MECHANICAL
1 Size
MarkMain Bearing
Bore DiameterCrank Shaft Main
Journal Diameter2 Size
Mark
Crank Shaft
Bearing
Size Mark
(Upper
Side)Crank Shaft
Bearing
Size Mark
(Lower
Side)
Oil Clearance
(Reference)
168.994-69.000
63.918-63.925
(2.5165-2.5167)2BlueBlue0.030-0.049
(0.0012-0.0019)
1(2.7163-2.7165)63.926-63.933
(2.5168-2.5170)1
BrownBrown
0.028-0.047
(0.0011-0.0019)
268.987-68.993
63.918-63.925
(2.5165-2.5167)2
BrownBrown0.029-0.048
(0.0011-0.0019)
2(2.7160-2.7163)63.926-63.933
(2.5168-2.5170)1
GreenGreen
0.027-0.046
(0.0011-0.0018)
368.980-68.986
63.918-63.925
(2.5165-2.5167)2
GreenGreen0.028-0.047
(0.0011-0.0019)
3(2.7157-2.7160)63.926-63.933
(2.5168-2.5170)1Ye l l o wYe l l o w0.026-0.045
(0.0010-0.0018)
Reassembly
1. Crankshaft (12)
Install the main bearings to the cylinder block and
the main bearing caps.
Be sure that they are positioned correctly.
Apply new engine oil to the upper and lower main
bearing faces.
NOTE: Do not apply engine oil to the main bearing back
faces.
015RS012
Carefully mount the crankshaft.
Apply engine oil to the thrust washer.
Assemble the thrust washer to the No.3 bearing
journal. The oil grooves must face the crankshaft.
015RS013
2. Rear oil seal (10)
Remove the oil from the cylinder block and the
retainer mounting surface.
Apply sealant (TB–1207B or equivalent) to the
retainer mounting surface, following the pattern
shown in the illustration.
The retainer must be installed within 5 minutes after
sealant application befor the sealant hardens.
Page 1030 of 6000
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ENGINE MECHANICAL
015RW002
Legend
(1) Around Bolt Holes
(2) Around Dowel Pin
Apply engine oil to the oil seal lip.
Align the cylinder block dowel pin holes with the rear
retainer dowel pins.
Tighten the rear retainer fixing bolts. New bolts
should be used when installing rear retainer.
Torque: 18 Nꞏm (1.8 Kgꞏm/13 lb ft)
NOTE: Be very careful not to disengage the oil seal garter
spring during installation of the rear retainer.
If the seal was removed from retainer for
replacement, apply engine oil to the oil seal lip and
install the oil seal using 5–8840–2286–0 oil seal
installer.
015RW001
015RS017
3. Flywheel (9)
1. Thoroughly clean and remove the oil from the
threads of crankshaft.
2. Remove the oil from the crankshaft and flywheel
mounting faces.
3. Mount the flywheel on the crankshaft and then
install the washer.
4. Hold the crankshaft to prevent from rotating then
install the bolts in the order shown to the specified
torque.
Torque: 54 Nꞏm (5.5 Kgꞏm/40 lb ft)
NOTE: Do not reuse the bolt and do not apply oil or thread
lock to the bolt.
015RS018
Page 1031 of 6000
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ENGINE MECHANICAL
4. Piston and connecting rod assembly (8)
Apply engine oil to the cylinder bores, the
connecting rod bearings and the crankshaft pins.
Check to see that the piston ring end gaps are
correctly positioned.
015RS019
Legend
(1) No.1 Compression Ring
(2) No.2 Compression Ring
(3) Oil Ring Side Rail Upper
(4) Oil Ring Side Rail Lower
(5) Piston Front Mark
Insert the piston/connecting rod assemblies into
each cylinder with the piston ring compressor. The
front marks must be facing the front of the engine.
Match the numbered caps with the numbers on the
connecting rods. Align the punched marks on the
connecting rods and caps.
Apply engine oil to the threads and seating faces of
the nuts.
Tighten the nuts.
Torque: 54 Nꞏm (5.5 Kgꞏm/40 lb ft)
After tightening the cap nuts, check to see that the
crankshaft rotates smoothly.
NOTE: Do not apply engine oil to the bearing back faces.
015RS020
5. Install oil gallery (7) and tighten the bolts in 2 steps, in
the order shown.
1st step: 29 Nꞏm (3.0 Kgꞏm/22 lb ft)
2nd step: 55
65
051RS009
6. Cylinder block side bolts (6)
Tighten all the bolts to the specified torque in the
order shown.
NOTE: Do not apply engine oil to the crank case side
bolts.
Torque: 39 Nꞏm (4.0 Kgꞏm/29 lb ft)
Page 1032 of 6000
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ENGINE MECHANICAL
012RS001
7. Install oil pump assembly (5), refer to “Oil pump” in
this manual.
8. Install oil strainer and O-ring (4).
9. Install oil pipe and O-ring (3) and tighten the bolts.
Torque: 25 Nꞏm (2.5 Kgꞏm/18 lb ft)
10. Install crankcase with oil pan (2).
1. Completely remove all residual sealant, lubricant
and moisture from the sealing surfaces. The
surfaces must be perfectly dry.
2. Apply a correct width bead of sealant (TB—
1207C or its equivalent) to the contact surfaces of
the oil pan. There must be no gaps in the bead.
3. The crankcase assembly must be installed within
5 minutes after sealant application to prevent
premature hardening of the sealant.
4. Tighten the bolts and nuts to the specified torque.
Torque : 10 Nꞏm (1.0 Kgꞏm/89 lb in)
013RW010
Legend
(1) Portion Between Bolt Holes
(2) Bolt Hole Portion
11. Install cylinder head assembly, refer to “Cylinder
head” in this manual.
Page 1033 of 6000
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ENGINE MECHANICAL
Piston and Connecting Rod
Piston, Connecting Rod and Associate Parts
015RW019
Legend
(1) Cylinder Head Assembly
(2) Cylinder Head Gasket
(3) Crankcase with Oil Pan
(4) Oil Pipe and O-Ring
(5) Oil Strainer and O-Ring
(6) Oil Gallery(7) Piston and Connecting Rod Assembly
(8) Piston Ring
(9) Piston Pin
(10) Piston
(11) Connecting Rod
(12) Connecting Rod Cap
Disassembly
1. Remove cylinder head assembly (1). Refer to
“Cylinder Head Removal” in this manual.
2. Remove cylinder head gasket (2).
3. Remove crankcase with oil pan (3). Refer to“Oil Pan
and Crankcase” in this manual.
4. Remove oil pipe and O-ring (4).5. Remove oil strainer and O-ring (5).
6. Remove oil gallery (6).
7. Remove connecting rod cap with connecting rod
lower bearing (12).
8. Remove piston and connecting rod assembly (7).
NOTE: Before removing piston and connecting rod
assembly, measure thrust clearance.
Page 1035 of 6000
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ENGINE MECHANICAL
015RV014The size mark (1) for piston outside diameter is
represented as shown in illustration below.
Outside Diameter
Size Mark A : 93.360 mm–93.370 mm
(3.6756 in–3.6760 in)
Size Mark B : 93.371 mm–93.380 mm
(3.6760 in–3.6764 in)
Size Mark C : 93.381 mm–93.390 mm
(3.6764 in–3.6768 in)
015RS025Measure the cylinder bore inside diameter (refer to
“Cylinder Block” in this manual).
012RS002
Piston Rings (8)
Any worn or damaged part discovered during engine
overhaul must be replaced with a new one.
1. Ring end gap measurement
Insert the piston ring into the bore.
Push the ring by the piston, at a right angle to the
wall, into the point at which the cylinder bore
diameter is the smallest.
Measure the ring end gap.
Compression Ring
1st ring
Standard:
0.300 mm–0.400 mm
(0.0118 in–0.0157 in)
Limit: 1.0 mm (0.0394 in)
2nd ring
Standard: 0.450 mm–0.600 mm
(0.0177 in–0.0236 in)
Limit: 1.2 mm (0.0472 in)
Oil ring
Standard:
0.150 mm–0.450 mm
(0.0059 in–0.0177 in)
Limit: 1.05 mm (0.0413 in)
