| Symptoms |
Possible Causes |
Remedy |
| Coolant Leakage |
- From the water pump drain hole
|
Visually inspect |
- Check for leaks after warming up the engine for approximately 10 minutes.
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- If coolant continues to leak, replace the water pump.
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- If the leak stops, reuse the water pump (do not replace it with a new pump).
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- From the gaskets or bolts
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- Check the tightening torque of the water pump mounting bolts.
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- Tighten the mounting bolts.
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- Check for damage to the gasket or contamination by dust.
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- Replace the gasket and clean off any dust.
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- From the outer surface of the water pump
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- Check the water pump material and check for cracks.
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- Poor material. If any crack is found, replace the water pump.
|
| Noise |
- From the bearings
- From the mechanical seals
- Impeller interference
|
Inspection using a stethoscope |
- After starting the engine, check for noise with a stethoscope.
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- If there is no noise, reuse the water pump (do not replace it).
|
- If there is noise from the water pump, remove the drive belt and recheck.
|
| Inspection after drive belt removal |
- After removing the water pump and drive belt, check the noise again.
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- If there is noise, reuse the water pump. Check the other drive part line.
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- If there is no noise, replace the water pump with a new one.
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| Check after water pump removal |
- After removing the water pump and drive belt, check the noise again.
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- If there is any interference between them, replace the water pump with a new one.
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| Overheating |
- Damaged impeller
- Loose impeller
|
Loose impeller |
- Corrosion of impeller blade
|
- Check the engine coolant.
- Poor coolant quality / maintenance
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- Separation of impeller from shaft
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