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ENGINE MECHANICAL
5. Install lower valve spring seat, valve spring and upper
valve spring seat then put split collars on the upper
spring seat, using the 5–8840–2446–0 valve spring
compressor and 5–8840–2547–0 valve spring
compressor adapter to install the split collars.
014RW042
6. Install tappet with shim.
7. Install camshaft assembly.
Refer to installation procedure for Camshaft in this
manual.
Valve Clearance Adjustments
NOTE: To adjust valve clearance, apply engine oil to the
cam as well as to the adjusting shim (2) with the cylinder
head built on the cylinder block, give a few turns to the
camshaft by means of timing pulley tightening bolt, and
measure valve clearance when the nose of cam is just
opposite to maximum cam lift (1) as shown in illistration
below.
014RW081
Legend
(1) Cam
(2) Shim
(3) Tappet
Valve Clearance Standard Value (cold)
Intake: 0.23 mm–0.33 mm
(0.0091 in–0.0130 in)
Exhaust: 0.25 mm–0.35 mm
(0.0098 in–0.0138 in)
Selection of Adjusting Shim
Shim to be selected = (Thickness of removed shim) +
(Valve clearance measurement – Standard valve)
Based on the above formula, the best suited shim should
be selected from 41 sorts of shim (differently thick at
0.02mm (0.0008 in) intervals from 2.40mm (0.0945 in)
through 3.2mm (0.1260 in) thick). Install the shim and
check valve clearance.
Page 1018 of 6000
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ENGINE MECHANICAL
Replacement of Shim
Let the cam push down the edge of tappet by using
5–8840–2444–0 valve clearance adjusting tool and push
out the shim with a flat blade screw driver as shown in
illustrations below.
014RW082
014RW083
014RW084
Page 1019 of 6000
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ENGINE MECHANICAL
Camshaft
Camshaft and Associated Parts
014RW040
Legend
(1) Camshaft Bracket Fixing Bolt
(2) Camshaft Bracket
(3) Camshaft Assembly Intake
(4) Camshaft Assembly Exhaust
(5) Pulley Fixing Bolt(6) Camshaft Drive Gear Pulley
(7) Retainer Fixing Bolt
(8) Retainer
(9) Camshaft Drive Gear
(10) Oil Seal
Disassembly
1. Remove fixing bolt (5) for camshaft drive gear pulley
using the 5–8840–2447–0 universal holder.
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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.
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Runout
Limit : 0.1 mm (0.0039 in)
014RW044
4. Measure the camshaft journal oil clearance.
1. Measure the camshaft bracket housing inside
diameter.
NOTE: Tighten camshaft bracket (2) to specified torque
before measuring the camshaft bracket inside diameter.
Torque : 10 Nꞏm (1.0 Kgꞏm/89 lb in)
014RW031
2. Subtract the camshaft outside diameter from the
camshaft bracket housing inside diameter.
Oil Clearance
Standard : 0.027 mm–0.078 mm
(0.0011 in–0.0031 in)
Limit : 0.11 mm (0.0043 in)
014RW037
5. Replace the cylinder head and/or camshaft if the
measured oil clearance exceeds the specified limit.
1. Carefully clean the camshaft journal, the
camshaft bracket, and the cylinder head.
2. Install camshaft assembly and camshaft brackets
(2), tighten twenty bolts (1) on one side bank to
the specified torque.
Torque: 10 Nꞏm (1.0 Kgꞏm/89 lb in)
014RW031
3. Measure the camshaft thrust clearance with a dial
indicator. Replace the camshaft and/or the
cylinder head if the camshaft thrust clearance
exceeds the specified limit.
Camshaft thrust Clearance
Standard : 0.03 mm–0.08 mm
(0.0012 in.–0.0031 in.)
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ENGINE MECHANICAL
Limit : 0.12 mm (0.0047 mm)
014RW035
Reassembly
1. Install camshaft drive gear assembly and tighten
three bolts to specified torque.
Torque: 10 Nꞏm (1.0 Kgꞏm/89 lb in)
2. Tighten sub gear setting bolt.
1. Use 5–8840–2443–0 to turn sub gear to right
direction until the M5 bolt hole aligns between
camshaft driven gear and sub gear.
2. Tighten M5 bolt suitable torque for prevent
moving the sub gear.
014RW041
3. Install camshaft assembly and camshaft brackets,
tighten twenty bolts on one side bank to the specified
torque.
1. Apply engine oil to camshaft journal and bearing
surface of camshaft bracket.2. Align timing mark on intake camshaft (one dot for
right bank, two dots for left bank) and exhaust
camshaft (one dot for right bank, two dots for left
bank) to timing mark on camshaft drive gear (one
dot).
014RW020
Legend
(1) Intake Camshaft Timing Gear for Right Bank
(2) Intake Camshaft Timing Gear for Left Bank
(3) Exhaust Camshaft Timing Gear
(4) Discerning Mark
LI: Left Bank Intake
RI: Right Bank Intake
LE: Left Bank Exhaust
RE: Right Bank Exhaust
Page 1023 of 6000
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ENGINE MECHANICAL
014RW023
Legend
(1) Right Bank Camshaft Drive Gear
(2) Left Bank Camshaft Drive Gear
(3) Timing Mark on Drive Gear
(4) Dowel Pin
014RW024
Legend
(1) Right Bank
(2) Left Bank(3) Alignment Mark on Camshaft Drive Gear
(4) Alignment Mark on Camshaft
(5) Alignment Mark on Retainer
3. Tighten twenty bolts in numerical order on one
side bank as shown in the illustration.
Torque: 10 Nꞏm (1.0 Kgꞏm/89 lb in)
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ENGINE MECHANICAL
014RW031
4. If the oil seal requires replacement, use the
5–8840–2445–0 to install the oil seal.
014RW034
5. Tighten bolt for camshaft drive gear pulley to the
specified torque using the 5–8840–2447–0 universal
holder.
Torque: 98 Nꞏm (10.0 Kgꞏm/72 lb ft)
014RW060