Polaris R09VA17AA, Service Manual

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3.50
ENGINE
Piston Failure - Scoring
• Lack of lubrication
• Dirt entering engine through cracks in air filter or ducts
• Engine oil dirty or contaminated
Excessive Smoke and Carbon Buildup
• Excessive piston-to-cylinder clearance
• Worn rings, piston, or cylinder
• Worn valves, guides or seals
• Restricted crankcase vent
• Air filter dirty or contaminated
Low Compression
• Decompressor stuck
• Cylinder head gasket leak
• No valve clearance or incorrectly adjusted
• Cylinder or piston worn
• Piston rings worn, leaking, broken, or sticking
• Bent valve or stuck valve
• Valve spring broken or weak
• Valve not seating properly (bent or carbon accumulated
on valve area)
• Rocker arm sticking
Backfiring
• ETC or speed limiter system malfunction
• Fouled spark plug or incorrect plug or plug gap
• Carburetion faulty - lean condition
• Intake / Exhaust system air leaks
• Ignition system faulty:
• Spark plug cap cracked/broken
• Ignition coil faulty
• Ignition or kill switch circuit faulty
• Ignition timing incorrect
• Sheared flywheel key
• Poor connections in ignition system
• System wiring wet
• Cam lobe worn or Valve sticking
• Lean condition
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