Page 1020 of 6000

6A–64
ENGINE MECHANICAL
014RW060
2. Remove twenty fixing bolts from inlet and exhaust
camshaft bracket on one side bank, then camshaft
brackets (2).
014RW027
3. Remove camshaft assembly (3), (4).
4. Remove three fixing bolts (7) from camshaft drive
gear retainer (8), then camshaft drive gear assembly.
Inspection and Repair
1. Use a micrometer to measure the cam lobe height
and uneven wear. Replace the camshaft if either the
lobe height or the uneven wear exceeds the specified
limit.
Lobe height : 44.709 mm (1.7602 in)
Uneven wear : 0.05 mm (0.0020 in)
014RW043
2. Use a micrometer to measure the diameter and the
uneven wear of the camshaft journals.
Replace the camshaft if the diameter or the uneven
wear exceeds the specified limit.
Journal Diameter
Standard : 25.972 mm–25.993 mm
(1.0225 in–1.0233 in)
Limit : 25.8 mm (1.0157 in)
Uneven wear : 0.05 mm (0.0020 in)
014RS023
3. Place the camshaft on V–blocks.
Slowly rotate the camshaft and measure the runout
with a dial indicator.
Replace the camshaft if the runout exceeds the
specified limit.
Page 1025 of 6000
6A–69
ENGINE MECHANICAL
Crankshaft
Crankshaft and Associated Parts
013RW009
Legend
(1) Cylinder Head Assembly
(2) Crankcase with Oil Pan
(3) Oil Pipe and O-Ring
(4) Oil Strainer and O-Ring
(5) Oil Pump Assembly
(6) Cylinder Block Side Bolts
(7) Oil Gallery(8) Piston and Connecting Rod Assembly
(9) Flywheel
(10) Rear Oil Seal Retainer and Oil Seal
(11) Main Bearing Cap
(12) Crankshaft
(13) Main Bearing Cap Fixing Bolts
(14) Oil Gallery Fixing Bolts
Disassembly
1. Remove cylinder head assembly (1). Refer to
“Cylinder Head” in this manual.
2. Remove crankcase with oil pan (2). Refer to “Oil Pan
and Crankcase” in this manual.CAUTION: Take care not to damage or deform the
sealing flange surface of crankcase.
3. Remove oil pipe and O-ring (3).
4. Remove oil strainer and O-ring (4).
5. Remove oil pump assembly (5).
6. Remove crankcase side bolts (6).
Page 1027 of 6000

6A–71
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 1028 of 6000

6A–72
ENGINE MECHANICAL
2. Measure the diameter and the uneven wear of main
journal and crank pin. If the crankshaft wear exceeds
the specified limit, crankshaft must be replaced.
Main journal diameter : 63.918 mm–63.933 mm
(2.5165 in–2.5170 in)
Crank pin diameter : 53.922 mm–53.937 mm
(2.1229 in.–2.1235 in.)
Uneven wear limit : 0.005 mm (0.0002 in)
015RS009
Crankshaft Bearing Selection
When installing new crankshaft bearings or replacing
bearings, refer to the selection table below. Select and
install the new crankshaft bearings, paying close
attention to the cylinder block journal hole.
1. Diameter size mark (1) and the crankshaft journal.
015RS010
2. Diameter size mark (1).
The diameter size marks are stamped on the No.1
crankshaft balancer as shown in the illustration.
015RS011
NOTE: Take care to ensure the bearings are positioned
correctly.
015RS012
Legend
(1) Number 1 and 4 main bearing upper and lower
(2) Number 2 and 3 main bearing upper
(3) Number 2 and 3 main bearing lower
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

6A–74
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

6A–75
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 1035 of 6000

6A–79
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)