2006 YAMAHA WOLVERINE 450 Owners Manual

8-15
8 2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
NOTE:If the spark plug shows a distinctly different color,
the engine could be defective. Do not attempt to di-
agnose such problems yourself. Instead, have aYamaha dealer check the ATV.2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.1. Spark plug wrench
Specified spark plug:
NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
U3C260E0.book Page 15 Tuesday, August 2, 2005 9:52 AM

8-16
82. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
NOTE:If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque assoon as possible.
4. Install the spark plug cap.EBU26421Engine oil and oil filter cartridge The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Place the ATV on a level surface.
2. Remove panel D. (See page 8-8.)
3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Wait a few minutes until the oil settles before
checking.
5. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag.
1. Spark plug gapTightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
U3C260E0.book Page 16 Tuesday, August 2, 2005 9:52 AM

8-17
8 6. Insert the dipstick in the filler hole (without
screwing it in), and then remove it again to
check the oil level.
NOTE:The engine oil should be between the minimumand maximum level marks.
7. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
8. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
9. Install the panel.
1. Engine oil filler cap
1. Dipstick
2. Maximum level mark
3. Minimum level mark
U3C260E0.book Page 17 Tuesday, August 2, 2005 9:52 AM

8-18
8To change the engine oil (with or without oil fil-
ter cartridge replacement)
1. Place the ATV on a level surface.
2. Remove panel D. (See page 8-8.)
3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect
the used oil.
5. Remove the engine oil filler cap, and then re-
move the engine oil drain bolt to drain the oil
from the crankcase.
NOTE:Skip steps 6–10 if the oil filter cartridge is not beingreplaced.
6. Remove panel C. (See page 8-8.)
7. Remove the oil filter cartridge with an oil filter
wrench.
1. Engine oil drain bolt
1. Oil filter cartridge
U3C260E0.book Page 18 Tuesday, August 2, 2005 9:52 AM

8-19
8
NOTE:An oil filter wrench is available at a nearby Yamahadealer.
8. Apply a thin coat of engine oil to the O-ring of
the new oil filter cartridge.
NOTE:Make sure that the O-ring is properly seated.
9. Install the new oil filter cartridge with an oil fil-
ter wrench, and then tighten it to the specified
torque with a torque wrench.
1. Oil filter wrench
1. O-ring
U3C260E0.book Page 19 Tuesday, August 2, 2005 9:52 AM

8-20
8
10. Install panel C.
11. Install the engine oil drain bolt, and then tight-
en it to the specified torque.12. Add the specified amount of the recommend-
ed engine oil, and then install and tighten the
engine oil filler cap.
CAUTION:ECB00300
In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.
Make sure that no foreign material enters thecrankcase.
1. Torque wrenchTightening torque:
Oil filter cartridge:
17 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque:
Engine oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter cartridge replacement:
2.30 L (2.43 US qt) (2.02 Imp.qt)
With oil filter cartridge replacement:
2.40 L (2.54 US qt) (2.11 Imp.qt)
U3C260E0.book Page 20 Tuesday, August 2, 2005 9:52 AM

8-21
8 13. Start the engine, and then let it idle for several
minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
14. Turn the engine off, and then check the oil lev-
el and correct it if necessary.
15. Install panel D.
EBU23381Final gear oil The final gear case must be checked for oil leak-
age before each ride. If any leakage is found, have
a Yamaha dealer check and repair the ATV. In ad-
dition, the final gear oil level must be checked and
the oil changed as follows at the intervals specified
in the periodic maintenance and lubrication chart.
To check the final gear oil level
1. Place the ATV on a level surface.NOTE:The final gear oil level must be checked on a coldengine.
2. Remove the final gear oil filler bolt, and then
check the oil level in the final gear case.
NOTE:The oil level should be at the brim of the filler hole.
3. If the oil is below the brim of the filler hole, add
sufficient oil of the recommended type to raise
it to the correct level.
4. Install the oil filler bolt, and then tighten it to the
specified torque.1. Final gear oil
2. Final gear oil filler bolt
3. Correct oil levelTightening torque:
Final gear oil filler bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
U3C260E0.book Page 21 Tuesday, August 2, 2005 9:52 AM

8-22
8To change the final gear oil
1. Remove the final gear case guard by remov-
ing the bolts.
2. Place the ATV on a level surface.
3. Place an oil pan under the final gear case to
collect the used oil.
4. Remove the final gear oil filler bolt and the fi-
nal gear oil drain bolt to drain the oil from the
final gear case.5. Install the drain bolt, and then tighten it to the
specified torque.
6. Add the recommended final gear oil to the
brim of the filler hole as shown.
1. Final gear case guard
2. Bolt
1. Final gear oil drain boltTightening torque:
Final gear oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
U3C260E0.book Page 22 Tuesday, August 2, 2005 9:52 AM