
ENGINE
4-48
ENGINE TURNS OVER BUT FAILS TO
START
◎
No fuel
◎
Dirt in fuel line or filter
◎
Fuel will not pass through fuel valve
◎
Fuel pump inoperative/restricted
◎
Tank vent plugged
◎
Carb starter circuit
◎
Engine flooded
◎
Low compression (high cylinder leakage)
◎
No spark (Spark plug fouled)
ENGINE DOES NOT TURN OVER
◎
Dead battery
◎
Starter motor does not turn
◎
Engine seized, rusted, or mechanical failure
◎
Kick start components damaged
ENGINE RUNS BUT NOT IDLE
◎
Restricted carburetor pilot system
◎
Carburetor misadjusted
◎
Choke not adjusted properly
◎
Low compression
◎
Crankcase breather restricted
◎
Air filter restriction
ENGINE IDLES BUT NOT REV UP
◎
Spark plug fouled/weak spark
◎
Broken throttle cable
◎
Obstruction in air intake
◎
Air box removed (reinstall all intake components)
◎
Incorrect or restricted carburetor jetting
◎
Reverse speed limiter limiting speed
◎
Carburetor vacuum slide sticking/diaphragm damaged
◎
Incorrect ignition timing
◎
Restricted exhaust system
◎
Cam Lobe worn
ENGINE HAS LOW POWER
◎
Spark plug fouled
◎
Cylinder, piston, ring, or valve wear or damage (check
compression)
◎
CVT not operating properly
◎
Restricted exhaust muffler
◎
Dirty carburetor
◎
Cam lobe worn
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
◎
Worn rings, piston, or cylinder
◎
Excessive piston-to-cylinder clearance
◎
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
Summary of Contents for AT56-69E
Page 35: ...MAINTENANCE 2 25 ...
Page 45: ...CVT SYSTEM 3 4 CVT EXPLODED VIEW ...
Page 56: ...ENGINE 4 3 ENGINE ILLUSTRATION ENGINE EXPLODED VIEW ...
Page 57: ...ENGINE 4 4 ...
Page 58: ...ENGINE 4 5 COOLING SYSTEM EXPLODED VIEW ...
Page 59: ...ENGINE 4 6 OIL FLOW DIAGRAM ...
Page 125: ...FUEL AND CARBURETOR 6 15 FUEL TANK SYSTEM ...
Page 135: ...BODY SUSPENSION STEERING 7 6 SUSPENSION ...
Page 142: ...BODY SUSPENSION STEERING 7 13 STEERING ...
Page 151: ...BRAKES 8 6 FRONT BRAKE EXPLODED VIEW MASTER CYLINDER ...
Page 196: ...ELECTRICAL 9 31 WIRE DIAGRAM ...