2007 Yamaha Motorsports Phazer FX Owners Manual - Page 64

2007 Yamaha Motorsports Phazer FX Manual

Page 64 highlights

CAUTION: @ Make sure that all cables, leads, etc., are routed properly before installing the covers. @ NOTE: @ When installing the covers, be sure to tighten the quick fasteners and the quick fastener screws securely. @ ESU03681 Checking the spark plugs The spark plug is an important engine component and is easy to inspect. The condition of the spark plug can indicate the condition of the engine. Check the coloration on the white porcelain insulator around the center electrode. The ideal coloration at this point is a medium to a light tan color for a snowmobile that is being ridden normally. If a spark plug shows a distinctly different color, there could be something wrong with the engine. For example, a very white center electrode porcelain color could indicate an intake track air leak or carburetion problem for that cylinder. Do not attempt to diagnose such problems yourself. Instead, take the snowmobile to a Yamaha dealer for inspection and possible repairs. You should periodically remove and inspect the spark plug because heat and deposits will cause a spark plug to slowly break down and erode. Consult a Yamaha dealer before changing to a different type of spark plug. Specified spark plug: R CR9EKB (NGK) Spark plugs are produced in several different thread lengths. The thread length or reach is the distance from the spark plug gasket seat to the end of the threaded portion. If the reach is too long, overheating and engine damage may result. If the reach is too short, spark plug fouling and poor performance may result. Also, if the reach is too short, carbon will form on the exposed threads resulting in combustion chamber hot spots and thread damage. Always use a spark plug with the specified reach. 8-9

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104

8-9
CAUTION
:
@
Make sure that all cables, leads, etc., are routed
properly before installing the covers.
@
NOTE:
@
When installing the covers, be sure to tighten the quick
fasteners and the quick fastener screws securely.
@
ESU03681
Checking the spark plugs
The spark plug is an important engine component and is
easy to inspect. The condition of the spark plug can indi-
cate the condition of the engine. Check the coloration on
the white porcelain insulator around the center electrode.
The ideal coloration at this point is a medium to a light
tan color for a snowmobile that is being ridden normally.
If a spark plug shows a distinctly different color, there
could be something wrong with the engine. For example,
a very white center electrode porcelain color could indi-
cate an intake track air leak or carburetion problem for
that cylinder. Do not attempt to diagnose such problems
yourself. Instead, take the snowmobile to a Yamaha
dealer for inspection and possible repairs. You should
periodically remove and inspect the spark plug because
heat and deposits will cause a spark plug to slowly break
down and erode. Consult a Yamaha dealer before chang-
ing to a different type of spark plug.
Spark plugs are produced in several different thread
lengths. The thread length or reach is the distance from
the spark plug gasket seat to the end of the threaded
portion. If the reach is too long, overheating and engine
damage may result. If the reach is too short, spark plug
fouling and poor performance may result. Also, if the
reach is too short, carbon will form on the exposed
threads resulting in combustion chamber hot spots and
thread damage. Always use a spark plug with the speci-
fied reach.
Specified spark plug:
R CR9EKB (NGK)