What to do if it squeaks
If there is an unusual squeal from the engine compartment, it is usually the V-belt's fault. Everything you need for clamping, changing and buying V-belts.
If under the hood the V-belt squeaks, you should do something. Not only because of the unpleasant sounds, but also because it can be dangerous for the engine.
The V-belt is one of the drive belts and is responsible for the supply of ancillary components. The belt itself is driven by the rotation of the crankshaft of the engine. It has a V-shaped cross section and transmits the engine power by the friction of the lateral flanks on the V-belt pulley. A further development of the V-belt is the V-ribbed belt, which is almost exclusively used in modern vehicles. Along the belt there are ribs on the underside. They reach into the grooves of the pulley. This makes it possible to realize smaller radii (wrap angles) than the V-shaped belt. Powered by the V-belt, among other things, the generator (generator), which in turn supplies the power for the on-board electrical system. In some cars, the V-belt also drives the power steering, the fan, the water pump, the hydraulic pump or the air conditioning compressor. V-belts are made of durable rubber, for stabilization inside there is a textile or steel cable insert. This allows very high torques to be transmitted. Some of the ancillaries are also driven by several V-belts.
In addition to the squealing noise from the engine compartment, other symptoms may indicate damage to the V-belt. So you can recognize a worn V-belt, for example, on the decrease in light. If this suddenly weakens, this can be an indication. Just like a stiff steering.
Unnecessary damage can be prevented by regular inspections and the eventual replacement of the V-belt. In general, the V-belt should not move more than one to two centimeters if you pull it firmly with your finger. It is also important that the V-belt is not brittle or cracked. At the same time, care must be taken to ensure that inlet tracks have formed. If the belt grinds in one place, the outer edges are often hardened or smoothed and shine under the light. Occasionally there are traces of rubber abrasion near the pulleys. Partly also whole pieces of the V-belt broke out. In the case of any form of damage or indications such as rubber marks, the V-belt should be replaced. The repair of a torn V-belt is basically not possible.
The spare part is standardized and usually costs between five and twenty euros. Who needs to buy a new V-belt, is not dependent on the original spare part from the manufacturer. V-belts can be bought in every specialized store and on the internet. There you get them usually cheaper than in the dealership. Anyway, the automaker does not design the V-belt itself: Suppliers like Continental are among the biggest producers. When buying the size of the V-belt is to be considered. There are differences in the material structure of the V-belt. If you are unsure, you can ask for help from a specialist.
However, retightening or changing is not common to all vehicle types possible. For some engines, the V-belt drives several ancillary units. An exchange or retightening is here consuming and sometimes only possible with special tools. Then a mechanic has to work. Relatively new are so-called Elast belts. They keep their tension on their own and do not require any additional clamping device, which lowers the manufacturing costs. To change the belt (about every 120,000 kilometers), a special tool is necessary, since a very high expenditure of force is necessary. Even if the length is the same, an Elastic strap should never be replaced with a standard non-stretch belt. He would either not mount or would not transmit the required forces.
Many cars have a tensioner that automatically tensions the V-belt. A manual retightening is not possible here. If the V-belt begins to squeak unpleasantly, this may also be due to a defect in the tension pulley, which must then be replaced, together with the V-belt. From an advanced mileage, it is no mistake to renew the tensioner when changing the V-belt.
Even if the pure material costs for a V-belt are low, replacement in a workshop can be expensive. Especially with newer vehicles. Many units are so tightly installed that it becomes harder to replace the V-belt. Covers and a part of the engine periphery must be disassembled to ensure access to the V-belt. As a rule, a workload of one to two hours is to be estimated for most current vehicle models, which means, depending on the hourly rate, between 50 and 150 euros for wages. In older cars, the replacement is often done after half an hour because there the V-belts are more accessible. In general, however, anyone who has no manual skills and automotive knowledge should leave the work to the professionals. Late effects can not be exploited and these can then increase the costs significantly. How long a V-belt holds can not be answered flat-rate. On average, one starts from around 90,000 kilometers or eight years.
At prices of between five and ten euros, V-belt sprays are offered. They should keep the V-belt supple and prevent annoying squeaks. However, the effect is controversial, experiences and opinions vary widely. A V-belt spray can be useful if the noise is due to the weather, so come from the wet and cold. If the sounds last longer, you can not avoid a visit to the workshop. Other home remedies should be avoided. Soap, candle or Spüli have to look for anything on the V-belt or in the engine compartment.
Not to be confused is the V-belt with the toothed belt. Because the belts have different functions. While the V-belt is used to drive ancillaries, the timing belt primarily synchronizes and drives the camshaft. The common feature: Often the timing belt is responsible for driving the water pump instead of the V-belt. The timing belt is made of a plastic composite material and has a strong toothing on the inside, so that it runs absolutely slip-free on the likewise toothed drive wheels. This is necessary so that the opening times of the valves do not get out of rhythm. While the V-belt should be regularly tensioned or changed during inspections, the timing belt must be replaced as a precaution from a certain age or a certain mileage. Because when the timing belt breaks, this is usually accompanied by great damage to the engine. Another common feature: V-belts and V-ribbed belts consist of a rubber compound similar to a toothed belt.
Just as the silk stocking has mostly given way to modern microfiber tights, so it has served as a breakdown helper. In vehicles that were manufactured in the middle of the last century, a torn V-belt could still be replaced by a woman's stocking makeshift. This is no longer possible with modern vehicles.