What causes the grinding fan-like sound when starting the car on rainy days?
3 Answers
Generally, the vehicle's fan serves the purpose of cooling down and is located in the middle position of the water temperature. The reasons are as follows: 1. Sound level: If the sound is loud, listen carefully to identify the type of sound. If it is soft and relatively uniform, there is no need to worry. If it is loud and noisy, inspect the fan blades for any issues. 2. Frequent activation: This mainly depends on the driving conditions. In urban areas, frequent activation is quite normal because the constant stop-and-go driving causes the engine to overheat, triggering the fan as a safety measure. However, if this happens frequently on highways, it is abnormal.
As someone who often drives in rainy weather, I think this noise is most likely caused by water or dirt on the fan blades creating friction when rotating. After rain, the engine compartment gets damp, making it easy for water droplets or leaves to accumulate near the fan. When the blades spin, they can produce that squeaking sound. Additionally, it's worth checking if the fan belt has aged, as a wet and slipping belt can also cause noise. If this is a new issue, open the hood on a sunny day to check if the fan is loose or if there are any foreign objects. Cleaning it promptly should resolve the problem. If you're still concerned, visit a professional auto shop to have the fan motor tested with instruments to ensure there are no major issues.
Once when I started my car after a heavy rain, there was a sound similar to a grinding fan, likely caused by water seeping into the fan belt area. After being washed by rainwater, the belt becomes more prone to slipping, creating unusual friction noises. It's recommended to immediately stop the car and inspect the fan area, using a dry cloth to clean the blades and belt, then wait for the water to dry before restarting. If the noise disappears, it indicates water damage. In the long term, replacing aged components is necessary to avoid engine overheating risks. While not a major issue, it shouldn't be ignored. Regular maintenance can prevent such problems.
