is this serpentine belt/ac belt in bad condition?

[jalikaria24]

I replaced the belts on my mazda 3 fairly recently. The a/c belt is a stretch belt and there is a tool for putting it on properly. I just put it around the crank started it on the a/c compressor and held it on with a few zip ties. Turned the engine over by hand and the belt climbed/stretched its self on to the pulley easily. The other belt you have pictured is easily replaced by just releasing the tensioner. I replaced the tensioner pulley while I was at it.

great! Did you use Mazda parts? Or aftermarket?

 

[jalikaria24]

got everything swapped! except whine is still there, most likely the alternator but whatever we will fix it when temps get better in new year

 

[AutoMechanic]

got everything swapped! except whine is still there, most likely the alternator but whatever we will fix it when temps get better in new year

What parts did you use?

 

[mk378]

While you have the belt off, you should spin each part by hand to check for noise, roughness, and wobble. If you hear anything at all it's likely going to be loud when running.

 

[nwjones18]

great! Did you use Mazda parts? Or aftermarket?

I used either Gates or Dayco belts, I can't remember which though...

 

[jalikaria24]

What parts did you use?

I used continental for all 3 which I think used to be called Goodyear. Only part store open

 

[jalikaria24]

While you have the belt off, you should spin each part by hand to check for noise, roughness, and wobble. If you hear anything at all it's likely going to be loud when running.

That was a good idea but completely forgot

 

[AutoMechanic]

I used continental for all 3 which I think used to be called Goodyear. Only part store open

That’s good. That is a good brand for parts.

 

[jalikaria24]

That’s good. That is a good brand for parts.

Yeah price was fair especially !

 

[DGXR]

I don't see anything wrong with that belt other than it seems to be drying out a little, the backing seems to be a lighter color than it should... hard to tell from pictures. Generally you should replace accessory drive "serpentine" belts around 100k miles if your pulleys are aligned and tensioned properly. Abuse or harsh operating conditions will shorten the life.
You can email Gates and they will send you a free belt check tool. It's a little piece of plastic you put between the ribs and it will tell you if the belt is OK or needs replacement.

 

[Snagglefoot]

A good way to access a belt is look at the backside of the belt and look for small cracks. This is a GM belt. Looks not bad from the outside but the inside shows cracking. Certainly time for replacement.

 

[jalikaria24]

anyone have an idea of what this noise is? its a whining noise and kinda sounds like an electric whining noise. i assumed it was the tensioner assembly asd the belts since those were worn so we replaced those but the noise didnt go away. it maybe got quieter by a tiny bit. heres a clip

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audio clip of noise

sorry the engine is idling so its a bit harder to notice the whining noise but its there, doesnt seem to do it when turning the wheel and its most prominent at idle. i stood outside in a parking lot while my friend drove the car slowly towards me and i can only seem to hear it when the car is at a full stop idle, i am not sure if maybe the engine noise masks it when it is driving but i am pretty positive that its only there during idle and full stop. going to buy a mechanic stethoscope in next few days but just wanted tips if anyone can identify it. for me it sounds like alternator whine but maybe it could be the water pump? or something else in that area.


**in person the noise is more trebly if that makes sense, the mic is picking up too much of the wind noise/fan noise so it sounds different, just focus on the whining noise plz*

thx!!

 

[AutoMechanic]

anyone have an idea of what this noise is? its a whining noise and kinda sounds like an electric whining noise. i assumed it was the tensioner assembly asd the belts since those were worn so we replaced those but the noise didnt go away. it maybe got quieter by a tiny bit. heres a clip

Streamable Video

Watch this video on Streamable.

streamable.com

audio clip of noise

sorry the engine is idling so its a bit harder to notice the whining noise but its there, doesnt seem to do it when turning the wheel and its most prominent at idle. i stood outside in a parking lot while my friend drove the car slowly towards me and i can only seem to hear it when the car is at a full stop idle, i am not sure if maybe the engine noise masks it when it is driving but i am pretty positive that its only there during idle and full stop. going to buy a mechanic stethoscope in next few days but just wanted tips if anyone can identify it. for me it sounds like alternator whine but maybe it could be the water pump? or something else in that area

thx!!

I’ve never heard a car make a noise like that so I can’t help on this one.

 

[mk378]

The other test that you should have done is to start the engine with the belts off to see if the noise you're chasing is even belt or accessory related. You can still remove the serpentine belt and try that. (If the belt turns the water pump don't let it run for very long.)

 

[mattd]

Carefully remove the oil fill cap on the valve cover while the car is running, does the noise go away when removed?

If it doesn’t, get the stethoscope out. Could be something as simple as a “singing” diode in the alternator

 

[jalikaria24]

The other test that you should have done is to start the engine with the belts off to see if the noise you're chasing is even belt or accessory related. You can still remove the serpentine belt and try that. (If the belt turns the water pump don't let it run for very long.)

noob mistake i know i should have done that but just felt like replacing the belts and tensioner would fix the issue, now i learned my lesson for next time

 

[jalikaria24]

Carefully remove the oil fill cap on the valve cover while the car is running, does the noise go away when removed?

If it doesn’t, get the stethoscope out. Could be something as simple as a “singing” diode in the alternator

sounds good thx will try that, if it does go away with the oil cap taken off, what does that mean?

i think its a alternator noise, it just sounds like such an electronic whine to me, its harder to tell from the video cuz the phone picsk up so much other noise. i dont know what a bad water pump or noisy water pump sounds like but ive heard some alternators so i think it could be that

 

[AutoMechanic]

sounds good thx will try that, if it does go away with the oil cap taken off, what does that mean?

i think its a alternator noise, it just sounds like such an electronic whine to me, its harder to tell from the video cuz the phone picsk up so much other noise. i dont know what a bad water pump or noisy water pump sounds like but ive heard some alternators so i think it could be that

I’ve never heard an alternator do that before but it could be that I guess.

 

[mattd]

sounds good thx will try that, if it does go away with the oil cap taken off, what does that mean?

i think its a alternator noise, it just sounds like such an electronic whine to me, its harder to tell from the video cuz the phone picsk up so much other noise. i dont know what a bad water pump or noisy water pump sounds like but ive heard some alternators so i think it could be that

A PCV system problem

 

[jalikaria24]

A PCV system problem

Thx for the reply! Have you had a vehicle that made this noise too?

the reason I ask is that the noise seems to be coming from the left side of the engine if I’m facing the engine, like standing at the hood. On the left side there’s the water pump, alternator, ac compressor. On the right side of the engine like the opposite side is the PCV I believe because it’s near the intake.