Possibly overtightened drive belts (1 Viewer)

[culturedredneck]

As I was replacing my alternator last week I decided to swap out the drive belts as well. I used gates belts. I'm now getting a loud whir/whine noise that makes me think a bearing is bad somewhere. It reminds me of the whine that a failing power steering makes. Ive checked the PS pump and its not making any noise while turning and fluid is not low.

After I swapped the belts it ran very quiet for the first hundred miles or so before this noise started. I am going to loosen the belt up, but I'm hoping someone could help me located the most likely culprit of the noise as Im having a hard time pinpointing it by sound alone. I fear that even if I loosen the belts there is some damage somewhere and I'd like to know where to start looking. I've included a couple of videos in which you can hear the whining noise.

Video 1:
Video 2:

 

[Rwhat]

You spin the a/c idler pulley to check the bearing? Is your idler for the alternator still there or removed?

 

[culturedredneck]

You spin the a/c idler pulley to check the bearing? Is your idler for the alternator still there or removed?

I'm not 100% sure what you're asking, but I have not removed the belts yet and tried to spin the AC idler pulley w/o belts to check anything yet. The alternator is new and I haven't removed anything form it.

 

[KC masterpiece]

It could actually be that your belts are now too loose after breaking in. I have always gone with the 1/2" of deflection under moderate finger pressure method for mine.

I would play with tension and if the sound does not go away remove and spin all the pulleys by hand to locate the culprit.

 

[Rwhat]

I'm not 100% sure what you're asking, but I have not removed the belts yet and tried to spin the AC idler pulley w/o belts to check anything yet. The alternator is new and I haven't removed anything form it.

The a/c idler bearing goes out and makes noise. Cheaper to just replace the bearing instead of the whole assembly. Just need a c clip pliers. Part number is posted somewhere on the forum.

I was asking if you checked the pulley when you had the belts off.

 

[gummycarbs]

The alternator is new

Is the noise coming from a bad bearing in the alternator?

 

[LC4LIFE]

I would replace the belts. Gates have been known to whine for years, actually decades at this point. OEM is better and most likely cheaper too.

Cogged belts

I bought my 80 a couple of weeks ago. It was making a horrible undulating/oscillating whine from the front of the engine, sounding a like a bearing heading south. The noise was so loud, it could be heard probably 50 yards away. >:( I used my mechanics stethescope to try and find the bad...

forum.ih8mud.com

Just replaced Belts with Gates on my LX450 now I can hear the

The belts that came off didn't have the cogs / teeth. Has anyone else cone down this path Tom 1997 LX450

forum.ih8mud.com

 

[robnicko]

are the belts the ribbed type by any chance as they can make that noise?

as others have said, OEM belts are best or even Bosch ones if you can get them

 

[BILT4ME]

As I was replacing my alternator last week I decided to swap out the drive belts as well. I used gates belts. I'm now getting a loud whir/whine noise that makes me think a bearing is bad somewhere. It reminds me of the whine that a failing power steering makes. Ive checked the PS pump and its not making any noise while turning and fluid is not low.

After I swapped the belts it ran very quiet for the first hundred miles or so before this noise started. I am going to loosen the belt up, but I'm hoping someone could help me located the most likely culprit of the noise as Im having a hard time pinpointing it by sound alone. I fear that even if I loosen the belts there is some damage somewhere and I'd like to know where to start looking. I've included a couple of videos in which you can hear the whining noise.

Video 1:
Video 2:

What year truck?

If 93+, do you have the alternator idler pulley on it? The gates cogged belts will whine against that pulley.

My Toyota belts I tighten until I can't deflect them because if I can, they start squealing.

It's either dye to cogged belts or you have a bearing going out on the alternator, or one of the two idlers. Get a $12 HF mechanics stethoscope and check it.

 

[WCBlueSky]

Tool to check belt tension is not expensive.

Adjusting belt tension on an 80 - good tool

At the 1000 mile mark on my rebuilt motor, I did a minor service that included adjusting the drive belts. The FSM gives specs to tighten the belts in pounds and indicates some expensive belt tension measurement device to get them to specification. I didn't have that tool so I ordered a Gates...

forum.ih8mud.com

 

[NLXTACY]

Toyota belts only. BTW, the spec is to retighten the belts AFTER 5 mins of use. Everyone puts them on way too loose.

 

[ChaseTruck]

Word in AZ was(is?) that Toyota belts don't hold up well to juiced fan clutches. So, Gates to the rescue. On our '93, those belts made the idler scream. The idler is no longer on that truck.

 

[lumbee1]

Drive belt tension:
New belt 90 − 130 lbf
Used belt 45 − 88 lbf

Air Conditioning belt tension
New belt 100 − 150 lbf
Used belt 60 − 100 lbf

 

[culturedredneck]

Toyota belts only. BTW, the spec is to retighten the belts AFTER 5 mins of use. Everyone puts them on way too loose.

After reading all the replies here I think it's likely the noise is coming from the ribbed Gates belts. Having the Gates PHH replacement I figured that would be a good replacement brand, but sounds like the ribs are a problem. OEM ones have been ordered and will be going on this weekend. I'll check all of the pulleys as well.

are the belts the ribbed type by any chance as they can make that noise?

as others have said, OEM belts are best or even Bosch ones if you can get them

They are ribbed. I'm swapping them out for OEM this weekend as it seems like this is a likely culprit. Thanks for the help.

 

[culturedredneck]

Thanks for all the help everyone. I think the most likely cause is the ribbed style gates belts so I'll start by swapping them out for OEM this weekend. If that doesn't work I'll check the pulleys and see where I'm at there. I had read about the gates belts being noisy before, but I figured that was referring to typical belt noises like squeaks and such. The threads that @LC4LIFE linked to describe it as a "supercharger" whine which is closer to what I'm hearing.

 

[Rwhat]

Thanks for all the help everyone. I think the most likely cause is the ribbed style gates belts so I'll start by swapping them out for OEM this weekend. If that doesn't work I'll check the pulleys and see where I'm at there. I had read about the gates belts being noisy before, but I figured that was referring to typical belt noises like squeaks and such. The threads that @LC4LIFE linked to describe it as a "supercharger" whine which is closer to what I'm hearing.

Well, I got dibs on the old gates belt. I want the supercharger whine.

 

[culturedredneck]

Thanks for all the help everyone. I think the most likely cause is the ribbed style gates belts so I'll start by swapping them out for OEM this weekend. If that doesn't work I'll check the pulleys and see where I'm at there. I had read about the gates belts being noisy before, but I figured that was referring to typical belt noises like squeaks and such. The threads that @LC4LIFE linked to describe it as a "supercharger" whine which is closer to what I'm hearing.

Well, I got dibs on the old gates belt. I want the supercharger whine.

If OEM fixes my problem, you're welcome to them. If you haven't done it already though, that modified blue fan clutch from Wits End will give you some sweet supercharger noises too.

 

[culturedredneck]

Alright, I've switched out the Gates belts for OEM belts and unfortunately the noise is still there. I tested the pulleys as best I could and didn't feel any rough spots or wobble in any of them, but I did find a noise coming from the water pump pulley. The noise is similar to what I'm hearing when the car is running. I've included a video of the sound. Any clue what this might indicate?

 

[NLXTACY]

Sure sounds like the water pump

 

[LC4LIFE]

Yeah, it should not sound like that.