The alternator belt whistles on a cold one

Many are familiar with the situation when a nearby car suddenly emits a strained and disgusting whistle, attracting the attention of all passers-by. It seems, a little more and, the car will either fly up vertically, or something very terrible will happen to it.

Meanwhile, everything is banal and simple. So the alternator belt whistles. And if such a whistle appears, it will not be able to pass by itself. It is necessary to carry out diagnostics, determine the cause and replace worn parts.

It so happens that the belt makes sounds during a cold start, and then, after the engine warms up, it returns to normal. In this case, they say that the alternator belt is whistling to a cold one.

And it so happens that the whistle does not stop even after prolonged engine operation. In this case, we are talking about the whistle of the belt under load.

Causes of the whistling of the alternator belt on a cold

Unpleasant sounds can occur at 2 points:

• starting the car engine after prolonged inactivity;
• starting the engine at subzero temperatures.

The main reason why the belt whistles on a cold one is belt slippage. This can be due to a number of factors:

• the alternator belt is not tight enough. The belt transmitting torque from the crankshaft is simply not able to accelerate the generator pulley and systematically slips on it;
• the generator bearing grease has thickened. This happens at low temperatures and the wrong lubrication option. The generator pulley is difficult to unwind, but then, reaching the required revolutions, it does not delay the rotation of the belt;
• the belt is worn out too much;
• the alternator belt or pulley is contaminated with oil, gasoline, antifreeze and other substances;
• belt of inadequate quality;
• problems with the generator, as a result of which the pulley is seized.

Belt whistles under load

If, after warming up the engine, the situation with an unpleasant sound does not change, this most often indicates more serious problems. In addition to the above reasons, this may be:

• wear of pulleys;
• wear of the generator rotor bearings;
• not parallelism of the pulleys;
• deformation of the pulleys;
• tension roller wear.

Diagnosis of the cause of the whistling belt

In order to try to determine the cause, it is necessary to carry out an inspection. To do this, you should:

• Locate the alternator belt and check for cracks and track integrity. The belt should not be worn out and worn out;
• Check belt tension. If the belt tension is weak, it should be strengthened using the Add to Dictionary roller or an adjusting bolt. An overly tensioned belt is also a source of sound and wears out parts of the generator and crankshaft faster;
• Check mating parts for cleanliness. They should be free of any contamination. the better the adhesion of the belt to the pulleys, the better the torque is transmitted and the higher the efficiency.

This is the first required inspection. However, it happens that it does not give results. Then the reason should be sought deeper:

• check the condition of the generator by trying to spin the pulley manually. If it rotates with difficulty, in fits and starts, or does not rotate at all, then, most likely, the generator bearing has failed and it will need to be replaced;
• check the belt tensioner pulley. It should spin easily and have no backlash. Any non-compliance with this requirement requires its replacement;
• check the parallelism of the pulleys. They should be on the same line, without curvatures and other deformations.

All of these factors are the main causes of whistling when the belt rotates. However, this does not eliminate the possibility of secondary indirect causes. The main thing is to listen to the work of your car to notice the slightest deviations from normal operation.

How to eliminate belt whistling

Having carried out diagnostics and knowing exactly the cause of the sounds, you can easily make repairs. Let's list what is being done in the first place:

• Purchase and installation of a new alternator belt. In this case, it is important to choose the original. Buying Chinese counterparts of dubious quality leads to an early replacement;
• Cleaning the belt and contacting elements from contamination;
• Tensioning or loosening the alternator belt. This is done using a roller or adjusting bolts;
• Replacing the generator bearing grease;
• Replacing the generator bearing;
• Replacing the tension roller;
• Replacing the alternator pulley;
• Generator repair.

We eliminate the whistle temporarily with autochemistry

It is worth mentioning the special conditioners and belt tensioners separately. In the cold season, they are very effective. The active substances in their composition soften the belts and make them more elastic, thereby increasing the adhesion to the pulleys.

If the belt looks good enough on the outside and the generator rotor is spinning, the first step is to use a spray conditioner. Perhaps it is simply that the belt has hardened at a low temperature.

Questions and answers:

What can be done to prevent the belt whistling? First of all, the whistle of the alternator belt appears when it is loosened. Therefore, to eliminate this sound, you need to tighten it well, and at the same time diagnose the generator shaft bearing.

What should be sprinkled on the generator belt so that it does not whistle? There are different belt conditioners for this. Some people lubricate the belt with dry or liquid rosin, as well as silicone grease. But these are temporary measures.

Can I drive a car if the belt whistles? In some cases, the whistle of the belt occurs when it is cold and in damp weather. When dry and warm, it stops whistling. But it is better not to ignore this symptom.

Why is the alternator belt whistling if it's new? A whistling sound occurs when the belt slips on the pulley. Therefore, the only solution to eliminate whistling is to tension a new belt.