Yamaha Waverunner 3 Manual

5-52
EPOWRCAMSHAFTS
5. Measure:
Camshaft journal diameter a 
Out of specification → Replace the cam-
shaft.
Within specification → Replace the cyl-
inder head and the camshaft caps as a
set.
Camshaft journal diameter:
24.44–24.45 mm 
(0.9622–0.9626 in)
Camshaft sprockets inspection
1. Check:
Camshaft sprocket
Wear/damage → Replace the camshaft
sprockets and timing chain as a set.
a1/4 of a tooth
bCorrect
1Timing chain
2Camshaft sprocket
Timing chain tensioner inspection
1. Check:
Timing chain...

5-53
EPOWRCAMSHAFTS
Camshaft installation
1. Install:
Exhaust camshaft sprocket 1 
Intake camshaft sprocket 2 
(with the special tool 3)
NOTE:
Install the camshaft sprocket with the punch
mark a facing outside.
Rotor holder:
YU-01235/90890-01235
T R..
Camshaft sprocket bolt:
24 N  m (2.4 kgf  m, 17 ft  lb)
2. Install:
Exhaust camshaft
Intake camshaft
Exhaust camshaft caps
Intake camshaft caps
Installation steps:
Turn the drive coupling counterclockwise,
and then check if cylinder #1 is at TDC...

5-54
EPOWRCAMSHAFTS
Install the exhaust and intake camshaft
caps.
NOTE:
Gradually tighten the intake and exhaust
camshaft cap bolts in 2–3 steps in the
sequence shown.
T R..
Camshaft cap bolt:
10 N  m (1.0 kgf  m, 7.2 ft  lb)
NOTE:
Make sure that the punch marks c on the
camshafts are aligned with the arrow marks
d on the camshaft caps.
Out of alignment → Reinstall.
Remove the wire from the timing chain.
10 1 4 5 8
17 5 1 4 8 15 9 12 149 3 2
7 6
18 7 3 2 6
13 11 10 16
3. Install:
Timing chain...

5-55
EPOWRCAMSHAFTS
Tighten the timing chain tensioner bolts
3 to the specified torque.
NOTE:
The “UP” mark on the timing chain ten-
sioner should face up.
T R..
Timing chain tensioner bolt:
10 N  m (1.0 kgf  m, 7.2 ft  lb)
Remove the screwdriver, make sure the
timing chain tensioner rod releases, and
then tighten the cap bolt to the specified
torque.
T R..
Cap bolt:
10 N  m (1.0 kgf  m, 7.2 ft  lb)
4. Turn:
Drive coupling
(several turns counterclockwise)
5. Check:
Turn the drive coupling...

5-56
EPOWRCAMSHAFTS
7. Install:
Cylinder head cover gasket
Cylinder head cover
NOTE:
Apply Gasket Maker® onto the mating sur-
faces of the cylinder head cover gasket and
cylinder head.
Tighten the cylinder head cover bolts stages
and in a crisscross pattern.
T R..
Cylinder head cover bolt:
12 N  m (1.2 kgf  m, 8.7 ft  lb) 

5-57
EPOWRCYLINDER HEAD
CYLINDER HEAD
EXPLODED DIAGRAM
REMOVAL AND INSTALLATION CHART 
Step Procedure/Part name Q’ty Service points
CYLINDER HEAD REMOVALFollow the left “Step” for removal.
Engine unit Refer to “ENGINE UNIT”.
Air filter case Refer to “FUEL INJECTION SYSTEM” in 
Chapter 4.
Exhaust pipe 3 Refer to “EXHAUST PIPE 3”.
Exhaust pipes 1 and 2 Refer to “EXHAUST PIPES 1 AND 2”.
Oil tank Refer to “OIL TANK”.
Intake and exhaust camshaft Refer to “CAMSHAFTS”.
1Bolt 2
2 Hunger 1
3Bolt 3
E
EE
E
E
E
24...

5-58
EPOWRCYLINDER HEAD
EXPLODED DIAGRAM
Step Procedure/Part name Q’ty Service points
4 Nut/washer 2/2
5 Nut/washer 8/8
6 Cylinder head 1
7 Cylinder head gasket 1
8 Dowel pin 2
Reverse the removal steps for installation.
E
EE
E
E
E
24
1
75 5
6
8 3
5
5
5
LT
271
2nd   49 N  m (4.9 kgf 
 m, 35 ft 
 Ib) 1st    20 N  m (2.0 kgf 
 m, 14 ft 
 Ib)
2nd   64 N  m (6.4 kgf 
 m, 46 ft 
 Ib) 1st    20 N  m (2.0 kgf 
 m, 14 ft 
 Ib)
10 N 
 m (1.0 kgf  m, 7.2 ft  Ib)
6 × 12 mm
10 N 
 m (1.0 kgf  m, 7.2...

5-59
EPOWRCYLINDER HEAD
SERVICE POINTS
Cylinder head removal
1. Remove:
Cylinder head bolts 1 
2. Remove:
Cylinder head nuts
NOTE:
Loosen the cylinder head nuts in the sequence
shown.
Cylinder head inspection
1. Eliminate:
Combustion chamber carbon deposits 
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damag-
ing or scratching:
spark plug bore threads
valve seats
2. Check:
Cylinder head
Damage/scratches → Replace.
Cylinder head water jacket
Mineral deposits/rust → Eliminate. 

5-60
EPOWRCYLINDER HEAD
3. Measure:
Cylinder head warpage
Out of specification → Replace the cyl-
inder head.
Cylinder head warpage limit:
0.1 mm (0.004 in)
Measurement steps:
Place a straightedge 1 and a thickness
gauge 2 across the cylinder head.
Measure the warpage.
If the limit is exceeded, replace the cylin-
der head.
Cylinder head installation
1. Install:
Cylinder head
NOTE:
Pass the timing chain through the timing
chain cavity.
Lubricate the cylinder head nuts with engine
oil.
Tighten the...

5-61
EPOWRCYLINDER HEAD
2. Tighten:
Cylinder head bolts 1 
NOTE:
Lubricate the cylinder head bolts with engine
oil.
T R..
Cylinder head bolt:
10 N  m (1.0 kgf  m, 7.2 ft  lb)