V-belt creaks - causes, repairs, costs. Guide

Probably every driver had such a problem. This is a squeaky engine accessory belt, often referred to as a V-belt or alternator belt. How can I fix this?

An inconspicuous engine accessory belt plays a very important role, as it drives the devices necessary for the operation of the power unit, such as a water pump and a generator. If it is used incorrectly, it will cause malfunctions in the car (for example, poor battery charging), and its failure will almost immediately prevent driving.

Two types of belts are used in cars: V-belts (in older cars) and multi-V-belts (modern solutions). Each of them wears out differently. The V-belt only works on its side edges. If they are worn out, they must be replaced.

The multi-V-belt, in turn, is adjacent to the pulleys with its entire surface. It's more efficient and quieter.

However, for both types of belts to work properly, they must be properly tensioned. – The tension is measured halfway between the pulleys. A properly tensioned belt should sag between 5 and 15 mm, says Adam Kowalski, a mechanic from Słupsk.

Moisture enhances the creak

A loose or worn belt may start to squeal when the engine is running. This phenomenon most often occurs in the cold season, and in summer in rainy weather. Why is this happening? Moisture worsens the frictional properties that occur between the belt and the pulley. Of course, this applies primarily to worn or faulty mechanisms, but this can occasionally happen in any car, even a new one, the mechanic explains.

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The squeal of the V-belt increases the more the load on the drive devices, such as the alternator, increases. So if the driver uses many current consumers at the same time (light, radio, wipers, etc.). In extreme cases, the squeak is almost continuous and does not depend on the weather.

Other problems

Squealing under the hood is not always caused by a loose or knotted belt. Sometimes the pulleys are to blame when they are already heavily skidded.

For example: a characteristic sign of wear on the power steering pump pulley is a creak that appears when the car's wheels are turned all the way.

Some manage to lightly sand the pulleys with fine sandpaper. Others spray them, and the strip itself, with a special preparation designed to eliminate creaking. “These treatments are half measures. Over time, the problem will return. Sometimes not only in the form of a squeak, but the belt will simply break, says Adam Kowalski.

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He believes that if the creaking continues after adjusting the tension, then the belt should be replaced and the pulleys checked. If they are slippery, they must be replaced with new ones.

“This is not a relatively large expense, and by eliminating creaking, we get rid of not only noise, but above all, we ensure the correct operation of various devices,” emphasizes the mechanic.

V-ribbed belt screeching can also come from belt grains or even small stones stuck in the grooves. Then it is better to replace the entire belt, because contamination is likely to be the cause of the damage.

Live

As mentioned, a properly tensioned engine accessory belt is critical to the proper operation of the vehicle and, of course, to the prevention of squealing. Most V-belts are equipped with automatic tensioners to maintain proper tension. But tensioners do not last forever and sometimes need to be replaced.

In the case of a V-belt, the correct tension must be set manually. This is not a difficult task, and experienced drivers can handle it on their own. However, in some vehicles, access to the belt is difficult, and sometimes it is necessary to drive into a canal or raise the car.

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Please note that too much tension is also undesirable. In this case, it will wear out prematurely, like pulleys.