Yamaha Fz6 N Service Manual

VALVES AND VALVE SPRINGS
5-20
For installation, reverse the removal proce-
dure.
Removing the valves and valve springs
Order Job/Parts to remove Q’ty Remarks 

VALVES AND VALVE SPRINGS
5-21
EAS24280
REMOVING THE VALVES
The following procedure applies to all of the 
valves and related components.
NOTE:
Before removing the internal parts of the cylin-
der head (e.g., valves, valve springs, valve 
seats), make sure the valves properly seal.
1. Remove: Valve lifter “1”
 Valve pad “2”
NOTE:
Make a note of the position of each valve lifter 
and valve pad so that they can be reinstalled in 
their original place.
2. Check:
 Valve sealing Leakage at the valve seat...

VALVES AND VALVE SPRINGS
5-22
EAS24290
CHECKING THE VALVES AND VALVE 
GUIDES
The following procedure applies to all of the 
valves and valve guides.
1. Measure: Valve-stem-to-valve-guide clearance
Out of specification  → Replace the valve 
guide.
2. Replace:  Valve guideNOTE:
To ease valve guide removal and installation, 
and to maintain the correct fit, heat the cylinder 
head to 100 °C (212 °F) in an oven.
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a. Remove the valve guide with the valve 
guide remover “1”.
b....

VALVES AND VALVE SPRINGS
5-23
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3. Eliminate: Carbon deposits (from the valve face and valve seat)
4. Check: Valve face Pitting/wear  → Grind the valve face.
 Valve stem end Mushroom shape or diameter larger than 
the body of the valve stem  → Replace the 
valve.
5. Measure:  Valve margin thickness “a”
Out of specification  → Replace the valve.
6. Measure:  Valve stem runout Out of specification 
→ Replace the valve.
NOTE:
 When installing a new valve, always replace...

VALVES AND VALVE SPRINGS
5-24
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a. Apply Mechanic’s blueing dye (Dykem) “b” onto the valve face.
b. Install the valve into the cylinder head.
c. Press the valve through the valve guide  and onto the valve seat to make a clear 
impression.
d. Measure the valve seat width.
NOTE:
Where the valve seat and valve face contacted 
one another, the blueing will have been 
removed.
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4. Lap: Valve face
 Valve seat
NOTE:
After replacing the cylinder head...

VALVES AND VALVE SPRINGS
5-25
h. Install the valve into the cylinder head.
i. Press the valve through the valve guide and onto the valve seat to make a clear 
impression.
j. Measure the valve seat width “c” again. If  the valve seat width is out of specification, 
reface and lap the valve seat.
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EAS24310
CHECKING THE VALVE SPRINGS
The following procedure applies to all of the 
valve springs.
1. Measure: Valve spring free length “a”
Out of specification  → Replace the valve...

VALVES AND VALVE SPRINGS
5-26
3. Measure: Valve spring tilt “a” Out of specification  → Replace the valve 
spring.
EAS24320
CHECKING THE VALVE LIFTERS
The following procedure applies to all of the 
valve lifters.
1. Check:
 Valve lifter Damage/scratches  → Replace the valve 
lifters and cylinder head.
EAS24340
INSTALLING THE VALVES
The following procedure applies to all of the 
valves and related components.
1. Deburr:  Valve stem end (with an oil stone)
2. Lubricate: Valve stem “1”
 Valve stem...

VALVES AND VALVE SPRINGS
5-27
4. Install: Valve cotters “1”
NOTE:
Install the valve cotters by compressing the 
valve spring with the valve spring compressor 
“2” and the valve spring compressor attach-
ment “3”. 5. To secure the valve cotters onto the valve 
stem, lightly tap the valve tip with a soft-
face hammer.
CAUTION:
ECA13800
Hitting the valve tip with excessive force 
could damage the valve.
6. Lubricate:
 Valve pad “1”
 Valve lifter “2” (with the recommended lubricant)
NOTE:
 Lubricate the...

GENERATOR AND STARTER CLUTCH
5-28
EAS4S81014
GENERATOR AND STARTER CLUTCH
Removing the generator and starter clutch
Order Job/Parts to remove Q’ty RemarksSeat Refer to GENERAL CHASSIS on page 4-1.
Fuel tank Refer to FUEL TANK on page 7-1.
Coolant Drain
Refer to CHANGING THE COOLANT on 
page 3-20.
Coolant reservoir tank Refer to RADIATOR on page 6-1.
Engine oil Drain
Refer to CHANGING THE ENGINE OIL on 
page 3-14.
1 Stator coil assembly lead coupler 1 Disconnect.
2 Generator rotor cover 1
3 Generator...

GENERATOR AND STARTER CLUTCH
5-29
11 Idler gear shaft 1
12 Idler gear 1
13 Starter clutch drive gear 1For installation, reverse the removal proce-
dure.
Removing the generator and starter clutch
Order Job/Parts to remove Q’ty Remarks