Why Is the Car Exhaust Fan So Noisy?

[OJudah]

The reasons for a noisy car exhaust fan are as follows: 1. Deformed fan blades: Check if the blades of the cooling fan are rubbing against foreign objects. If not, the fan may be damaged. 2. Motor failure: The motor of the exhaust fan inside the air conditioner may be damaged, and it is recommended to replace the exhaust fan. 3. Dirt accumulation: If there is excessive dirt inside the air conditioner, cleaning the air conditioner is advised. 4. Excessive wear: Inspect the radiator and surrounding components to see if the bearings are excessively worn. 5. Excessive gap: Check if the horizontal and vertical gaps of the motor rotor shaft are too large, or if the motor rotor is rubbing against the stator.

[LeRowan]

I've been driving for over 20 years, and loud radiator fan noise is often caused by mechanical issues. The fan blades might be bent, deformed, or obstructed by stones, causing a humming sound at high speeds. Worn bearings can also create friction noise, sounding like metal grinding. If not addressed promptly, it may affect water pump or radiator performance, leading to poor engine cooling and overheating. I recommend first using a high-pressure water spray to clean debris from the radiator fins. If the noise persists, visit a repair shop to inspect the bearings or replace the fan to prevent system failure.

[LaAnthony]

As a long-haul driver, when I encounter a sudden loud noise from the radiator fan, it's usually caused by electrical system issues. The fan relay may have poor contact or be burnt out, causing it to operate at full speed instead of regulating properly, resulting in a roaring sound. Another common cause is worn carbon brushes in an aging electric motor, leading to unstable current and loud noise. This signal indicates insufficient cooling, and the engine temperature may be too high. It's necessary to stop and inspect as soon as possible to avoid breaking down on the road.

[VonParker]

During routine vehicle maintenance, I've noticed that excessive noise from the cooling fan is often caused by dust accumulation or insufficient lubrication. Dust adhering to the blades creates imbalance during rotation, producing a hissing sound, while dry fan shaft friction increases noise levels. Regular cleaning of the radiator fins and applying lubricating oil can significantly reduce noise while extending fan lifespan - saving both money and effort.