SPB type various transmission beltsV-beltNoise diagnosis method

above-mentionedV-beltDirt or sand particles between the pulleys can also cause the above-mentioned noise, so if a car is working in a relatively dirty environment, check whether there is dirt on the surface of all pulleys. The craze for buying air has told me that it is very necessary to do so.

Although the surface of the pulley may be contaminated with sand or other dirt, or if the used belt is installed in reverse, it can also cause problemsV-beltMake a long scream or piercing noise, but it is usually caused by improper assembly of the auxiliary mechanism drive device.

Rumble sound is a typical sound produced by belt vibration, especially when the auxiliary transmission system is under load. When the engine reaches a certain speed, the noise will significantly increase. The cause of such faults is generally due to the transmission belt being too loose, stretched too long, or the belt tensioner or tensioner wheel being damaged.

mostV-beltThere is a set of belt wear length indicator marks at a certain point along the slide direction between the bottom of the automatic tensioner and the tensioner arm. This symbol consists of a pointer and two to three markings, indicating the working range of the belt tensioner. If the pointer exceeds this range, the belt is probably stretched too long and should be replaced.

Hissing, creaking, roaring, or whining sounds

On a vehicle without an automatic belt tensioner installed, measure with a standard belt elongation gauge at the middle position between the two pulleys. If there is a difference from the standard value, replace the belt.

Take the timing gear belt as an example, it should be adjusted immediately after installation. That is why it is necessary to indicate the direction of rotation of the timing gear belt. If the timing gear belt is removed and installed backwards due to other maintenance work, you will hear sharp and piercing screams when the belt is running. Try reversing the installation direction of the belt and see if the fault disappears.

Rumble sound:

If the continuous roar gradually turns into a whining sound as the engine speed increases, it indicates that the corresponding bearings will soon fail. Repeat the above experiment to avoid system disasters at critical moments.

Continuous hissing or creaking sounds that increase with the increase of engine speed usually indicate a lack of oil in the bearings of the auxiliary transmission mechanism. With the help of a stethoscope, you can further listen to these noises. Then remove the drive belt and manually rotate the suspected faulty component. If the rotation is difficult or the sound is rough, harsh, or makes a grating sound, do not hesitate to replace the bearing or the corresponding component. But it should be noted that every time the components of the auxiliary transmission mechanism are replaced, do not forget to replace the belt tensioner and automatic tensioner.

If the belt is not excessively stretched and the automatic tensioner is in good working condition, check if the working surface of the belt is polished as smooth as a mirror. This is a typical slip phenomenon caused by excessive belt wear under load, and the paint peeling off the surface of the pulley is proof of the slip phenomenon.

If the transmissionV-beltIf the elongation of the car does not exceed its limit, then if your car is equipped with an automatic tensioner, you should pay close attention to it. Firstly, start the engine and load the auxiliary transmission mechanism as much as possible (such as turning on lights, air conditioning, rotating wheels, etc.), then observe the cantilever of the belt tensioner; During engine operation, there should be a small displacement of the belt tensioner suspension pipe. If the belt tensioner cantilever does not move, turn off the engine and manually move it within the working stroke of the belt tensioner suspension pipe, with a displacement of approximately 1/4 inch. If the cantilever of the belt tensioner cannot move, it indicates that the belt tensioner has failed and should be replaced in a timely manner; If the displacement of the belt tensioner cantilever exceeds 1/4 inch, it indicates that the spring load is too small, which will cause the belt to slip. Measure again. If it still does, it must be replacedV-beltTensioner.

V-beltSqueezing sound:

As I mentioned earlier, faults in the auxiliary mechanism transmission system are indeed quite common in some car models. I believe the above diagnostic techniques can help you diagnose and eliminate such transmission belt noise faults.

If the belt squeaks and makes noise only in humid weather, and the surface of the belt and pulley is relatively smooth. Let's do the same experiment: let the auxiliary mechanism drive system work under load, while using a water bottle to sprinkle water on the belt. If there is a sound, replace the belt.

If the above noise occurs on a newly driven car, it may be caused by poor assembly quality at the original manufacturing factory. Check the relevant components that you believe may have caused the malfunction. If the above noise occurs in an old car, then you should consider whether some related accessories of its auxiliary mechanism drive device need to be replaced. Carefully observe the components that may have been replaced (such as the AC generator, power steering pump, etc.) to see if their mounting brackets are secure and reliable. At the same time, it is important to pay attention to whether there are washers or bushings left behind during the installation process, as they may also cause misalignment of the pulley assembly.

V-beltLong screaming or piercing noise:

V-beltMaking a squeaking sound generally indicates a significant decrease in the friction coefficient of the belt surface and excessive wear. If there is a noise when the vehicle is under load, you may want to observe one of the transmissionsV-beltYou will find that the resistance or elasticity on the belt, belt automatic tensioning device, or belt tensioning wheel will increase abnormally. http://www.chifengpd.com/shchifeng-News-77547/