factory sale SAIC MAXUS V80 C00015256 generator belt

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Use your ears to listen to the analysis of the abnormal sound of the car engine belt

The squeaking sound of the belt generally means that the friction coefficient of the belt surface has been greatly reduced and has been excessively worn. If there is a rattling sound when the vehicle is under load, look at one of the drive belts and you will notice an unusual increase in the resistance or spring force on the belt tensioner or on the belt tensioner.

Most automatic belt tensioners have a set of belt wear length indicators somewhere between their base and the tensioner arm, along the direction of the chute. The sign consists of a pointer and two or three markings, which indicate the working range of the belt tensioner. If the pointer is outside this range, the belt is probably stretched too long and should be replaced. On vehicles without an automatic belt tensioner, measure with a standard belt stretch gauge halfway between the two pulleys. If there is a difference from the standard value, it is better to replace the belt.

If the drive belt doesn't stretch beyond its class limit, then if your car has an automatic tensioner, you should pay close attention to it. First, start the engine, load the auxiliary drive configuration as much as possible (such as turning on the lights, air conditioning, turning the wheels, etc.), and then observe the belt tensioner cantilever; while the engine is working, the belt tensioner cantilever should have a small displacement quantity. If the belt tensioner hanger does not move, turn off the engine and manually move it within the working stroke of the belt tensioner hanger, approximately 0.6 cm. If the belt tensioner cantilever cannot move, it means that the belt tensioner has failed and should be replaced in time; if the displacement of the belt tensioner cantilever exceeds about 0.6 cm, it means that the spring load is too small, which will cause the belt to slip. This way, only the belt tensioner is replaced.

If the belt is not overstretched and the automatic tensioner is working well, see if the working surface of the belt is mirror polished. This is a typical slippage under load caused by excessive belt wear, and the paint peeling off the surface of the pulley is the best proof of slippage.

If the belt creaking often occurs in wet weather, and the surface of the belt and pulley is relatively smooth. Let's do the same experiment: let the auxiliary configuration work with the system under load, while spraying water on the belt, and if it rattles, replace the belt.

Long screams or harsh noises:

Although the surface of the pulley is stained with dirt such as sand particles or the reverse installation of the used belt can also cause the belt to make a long squeal or screeching noise, it is usually caused by improper assembly of the auxiliary device.

If the above noise occurs on a new car that has been driven a while back, it may be caused by poor quality original factory equipment. Check for components that you think may be causing the failure. If the above noise occurs in an old car, then you should consider whether some accessories related to its auxiliary drive unit need to be completely replaced. Carefully observe accessories that may have been finely replaced (such as generators, steering assist pumps, etc.) to see if their mounting brackets are secure. It may also cause misalignment of the pulley.

As mentioned above, dirt or sand between the belt and pulley can also cause the above noise, so if the car is used in a relatively dirty environment, check the surface of all pulleys for dirt.

Take the timing gear belt as an example, it should be adjusted immediately after installation. This is why the direction of rotation of the timing gear belt is marked. If the timing gear belt is removed and installed upside down due to other maintenance work, you will hear a high-pitched, screeching squeal when the belt is running. Try reversing the orientation of the belt and see if the fault goes away.

Hissing, rattling, growling, or chirping:

A continuous hissing or rattling sound that increases as the engine revs increases, usually means the auxiliary rotating mechanism's bearings are starved of oil. These noises can be further checked with the aid of a stethoscope. Then remove the drive belt and turn the suspected faulty component by hand. If the rotation is difficult or the sound is rough and rattling, do not hesitate to replace the bearing or replace the corresponding part. But it should be noted that every time you replace the parts of the auxiliary drive accessories, you must not forget to replace the belt tensioner and the automatic tensioner. If the continuous roar gradually turns into a roar as the engine speed increases, it indicates that the corresponding bearing will soon fail.

Rumble

Rumble is a typical belt vibration sound, especially when the auxiliary mechanism drive system is operating, when the engine reaches a certain speed, the noise will increase significantly. The cause of this type of failure is generally due to the transmission belt being too loose, stretched too long, or the belt tensioner and tensioner being damaged.