Polaris Supersport 2007, Руководство по обслуживанию

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5.6
Engine Systems
9923396 - 2007-2012 EDGE/Widetrak LX Service Manual
©2011 Polaris Sales Inc.
any up and down movement detectable in the big end
bearing.
Piston Needle Bearing
1. Clean the end of the connecting rod and inspect inner
bore with a magnifying glass. Look for any surface
irregularities including pitting, wear, or dents.
2. Run a fingernail around the inside of the rod and check
for rough spots, galling, or wear.
3. Oil and install needle bearing and pin in connecting
rod.
4. Rotate pin slowly and check for rough spots or any
resistance to movement.
5. Slide pin back and forth through bearing while rotating
and check for rough spots.
6. With pin and bearing centered in rod, twist ends back
and forth in all directions to check for excessive axial
play.
7. Pull up and down evenly on both ends of pin to check
for radial play.
8. Replace pin and bearing if there is any resistance to
rotation or excessive axial or radial movement. If play
or roughness is evident with a new pin and bearing,
replace the connecting rod.
Crankshaft Index
Polaris crankshafts are pressed together. The connecting
rod journal center lines are indexed 180° apart from each
other.
It is sometimes necessary to check multi-cylinder
crankshafts to verify that one cylinder has not been forced
out of position relative to the other cylinder. Some causes
for a “out of index” crankshaft include but are not limited to
the following:
• Hydrolock from water or fuel
• Impact to drive clutch from object or accident
• Abrupt piston or other mechanical failure
• Engine lock-up due to drive belt failure
Symptoms of an out of index crankshaft can include but
are not limited to the following:
• Difficulty calibrating carburetor (repetitive plug
fouling on one cylinder with no other cause)
• Unexplained piston failure on one cylinder (i.e.
severe detonation, broken ring lands, etc.)
• Excessive vibration of engine, back-firing, etc.
• Rough idle, poor top speed.