HYOSUNG 2010 ST7 Service Manual page 266

Complaint
Dirty or heavy
exhaust smoke.
Slipping clutch.
Dragging clutch.
Transmission will
not shift.
Transmission will
not shift back.
Transmission
jumps out of
gear.
RADIATOR (COOLING SYSTEM)
Complaint
Engine over-
heats.
Engine over-
cools.
Symptom and possible causes
1. Too much engine oil in the engine.
2. Worn piston rings or cylinders.
3. Worn valve guides.
4. Cylinder wall scored or scuffed.
5. Worn valves stems.
6. Defective stem seals.
7. Worn side rails.
1. Weakened clutch springs.
2. Worn or distorted pressure plates.
3. Distorted clutch plates or pressure plates.
1. Some clutch springs weakened while others are not.
2. Distorted pressure plates or clutch plates.
1. Broken gearshift cam.
2. Distorted gearshift forks.
3. Worn gearshift pawl.
1. Broken return spring on shift shaft.
2. Rubbing or sticky shift shaft.
3. Distorted or worn gearshift forks.
1. Worn shifting gears on driveshaft or countershaft.
2. Distorted or worn gearshift forks.
3. Weakened stopper spring on gearshift stopper.
Symptom and possible causes
1. Not enough engine coolant.
2. Radiator core clogged with dirt or scale.
3. Faulty cooling fan.
4. Defective cooling fan thermo-switch.
5. Clogged water passage.
6. Air trapped in the cooling circuit.
7. Defective water pump.
8. Use of incorrect engine coolant.
9. Defective thermostat.
1. Defective cooling fan thermo-switch.
2. Extremely cold weather.
3. Defective thermostat.
SERVICING INFORMATION 9-10
Remedy
Check with inspection win-
dow, drain out excess oil.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Remedy
Add coolant.
Clean.
Repair or replace.
Replace.
Clean.
Bleed out air.
Replace.
Replace.
Replace.
Replace.
Put on the radiator cover.
Replace.