Engine Run Sluggish (Speed Does Not Pick Up, Lack Of Power) - SANYANG INDUSTRY CO. SYM Service Manual

SYM
B. Engine run sluggish (Speed does not pick up, lack of power)
Check and adjustment
Try gradual acceleration
and check engine speed
Engine speed can be
increased.
Check ignition timing
(Using ignition lamp)
Ignition timing correct
Check cylinder compression
pressure (using compression
pressure gauge)
Compression pressure correct
Check if carburetor jet is
clogged
No clogged
Remove spark plug
No foul or discoloration
Check if engine over heat
Normal
Continually drive in
acceleration or high speed
No knock
1. GENERAL INFORMATION/TROUBLE DIAGNOSIS
Fault condition
Engine speed can not be
increased.
Incorrect ignition timing
No compression
Fouled and discoloration
Engine overheat
Clogged
Knock
Probable causes
1. Air cleaner clogged
2. Poor fuel supply
3. Lines in fuel tank evaporation
system clogged
4. Exhaust pipe clogged
5. Fuel level too low in carburetor
6. Fuel nozzle clogged in
carburetor.
1. Malfunction of CDI
2. Malfunction of AC alternator
1. Cylinder & piston ring worn out
2. Cylinder gasket leaked
3. Sand hole in compression parts
4. Valve deterioration
5. Seized piston ring
1. Remove foreign
1. Remove dirt
2. Incorrect spark plug heat range
1. Piston and cylinder worn out
2. Lean mixture
3. Poor fuel quality
4. Too much carbon deposited in
combustion chamber
5. Ignition timing too advanced
6. Poor circuit on the cooling
system
1. Too much carbon deposited in
combustion chamber
2. Lean mixture
3. Poor fuel quality
4. Ignition timing too advanced
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