Belt (again) or tensioner? Or something else?

[Swimupstream]

I've followed a few of the threads and sought some help a few months ago in one (http://www.toyota-4runner.org/4th-g...-if-you-need-change-one-v6-2.html#post2994685), no luck. Figured I'd try a new thread since I am legal to do one now.

2005 V6 4WD SR5
Purchased 5y ago at 150k, now at 201k

Changed my serp (3y old) belt after typical belt squealing and whining (mostly mornings, cold, wet, but not always and sometimes when warm and running), and the noise went away for a couple months. After a while noise started returning and some groaning and some other noises crept in over time.

• Eventually replaced the Idler 1 (very bottom). Groaning immediately stopped, but squeal was still there.
  
• Replaced the belt (change #2). Squealing went away.

Within a month or two squealing started again and has progressively gotten worse.

• Tensioner pulley felt a little (really getting picky) rough spinning. Replaced the tensioner bearing. It did feel much better spinning (prob expected at 200k!) but ZERO change to the noise.

Thoughts? Tensioner? Alignment? Another pulley/bearing? Or just bad luck on belts?

If it's simply the belts, which I'm about to do but hate to waste my money, why have I gone through three belts and 24 months? (Would be sooner but I just keep driving around with the noise!)

I don't want the tensioner answer but... before I do it I guess I just want some good 4R fieldbase opinions. B'c shops and dealer have gotten me nowhere.

Cheers.



(I know there are a couple of other threads that echo much what I'm talking about here and there, but nothing definitive, and most are 7 or 8 years old. e.g. Serp Belt Squeeling constantly now '03 V6 So feel free if I need to redirect to another thread, but I can't post new yet.)

 

[TowMeOut]

Hmmm,
Groan, growl, whine, etc. seems to normally be bearing related. A squeal I always figured indicated the belt slipping. It's untelling which pulley it might be slipping on since it sounds like this occurs a lot. Does it get any better worse when you impact the belt load (turn the tires with the truck stopped, AC cycling, heavy alternator load, etc.)?

I just went through similar issue with 3 of the idler pulleys. I had a racket from at least one but wasn't 100% sure which. Looking closely I could see a faint wobble so I figured better safe than sorry. I swapped the bearings based on some threads here and used some cheapo bearings from Amazon. That was false economy since one of them only last about 90 days before it was spitting out parts. Since then I found an OEM-ish set on Ebay (used Koyo Japanese bearings but the pulleys appear to be made in China). So far so good.

A couple of things you might try..... Get a squirt bottle of plain water and put some on the suspect pulley when the squeal starts. Juice it up and if the noise goes away that's your likely culprit. You kind of only get one shot though since once the belt gets wet you're hitting up everything. Also, put the belt on backwards (reverse direction). I don't believe these belts are directional in any way but perhaps it's worn in a particular way (like cupping for a set of tires) and that's causing some of the noise.

 

[Swimupstream]

I have done the water/lube on the belt and pulleys. Belt-- gets quiet for a split second then all hell breaks loose louder than ever like a banshee is gonna come flying out of the engine and whop me. The pulleys, not so much response.

I haven't tried the reverse belt consideration. I'll see about giving that a shot this afternoon if time allows.

Thx.

 

[kgbagent]

Need more info. When you mentioned you replaced the tensioner bearing, was it just the bearing or did you replace the entire pulley/bearing assembly? And what brand did you use? Same question for the other idlers.

Search my posts on the subject (I also have a 2005 V6) as I think I am the only one who has pointed out the fact that Toyota has superceded many of these idlers and they now require very specific spacers to line up with the belt correctly.

 

[nevada]

the tensioner isn't keeping the belt tight enough, and its slipping on one of the pulleys slightly.
the spring is weak, replace the tensioner and the belt will stop squeaking.

 

[Swimupstream]

Tow- realized I didn't finish answering your question. No change in stationary loading. Park or neutr louder than drive, and once driving throttle obviously louder.

didn't get to reverse the belt yesterday, if I don't get to do it tonight I'll have plenty of time tomorrow give that a shot.

KB- Gates on the bottom Napa unspecified up top. Just did the bearing up top because I was trying to be frugal (hehehe) not have to buy a whole nother pulley if it was just the bearing that was bad. (Plus, I hate making trash when I don't have to.) Very familiar with the your threads, one of the only reasons I got this far, thanks for jumping in here.

Nevada thanks! Kind of some of the definitiveness I'm trying to consider. Keep thinking if I buy the tensioner, and put it on & the belt is now screwy, I won't know the true culprit! And vice versa. LOL Hoping the belts not to beat up and the tensioner alone will do it so I have a definitive no yes or no. Goal is get rid of the sound and slip, but without replacing more or $ than needed

 

[waypoint]

You can narrow your focus to belt slippage by applying a light film of plain white toothpaste to the grooved side of the belt surface. The mild abrasives in the toothpaste will remove glazing on the belt and drive pulleys that may have occurred while it was slipping, restoring grip.

If this cures your noise, I'd replace the belt and observe for the new one to start squealing again. If this happens, your tensioner is not maintaining proper belt pressure as someone stated above. The tensioner is a bear to replace as it's located between the AC compressor and engine block...compressor has to be unbolted and moved out of the way in order to access the tensioner bracket bolts.

If this has no effect on your noise, it's one of the idler pulleys or driven components.

 

[Swimupstream]

Tensioner wobble

You all are awesome! Thanks Waypoint. That's exactly (and an extra $100) why I want to be 99.9% sure before I do it.

*Here's something my buddy just noticed*-- the tensioner pulley shimmies a bit, more in neutral and park, less in drive and less when throttled (sensible). Part of my brain says it should shimmy, the other part says it shouldn't enough to be noticeable w no load or changes.

Video attached, in park, no load. Video of course isn't as obvious as in person.

https://photos.app.goo.gl/HuEfHzbQgDTyk17t8
Normal or slam dunk answer?

(Just reversed the belt, now just gotta wait for it to cool and see what happens in the AM. I'll throw that home remedy cleaner on there too, keeping the focus on the belt.)

 

[Swimupstream]

Belt reversal and toothpaste, no dice. Actually hearing it a LOT more right now, much longer and even warm; more with throttle, more in neutral.

I am more and more convinced it is another bearing/pulley. The sound is just a lot more screachy and rough than a belt sqeak. (But I know sounds can be deceiving in engines.)

Think I'm gonna do a little bit of pulley play later. Hate to go through the whole swap of that tensioner when it was just the pulley, or worse do the pulley and needed the whole tensioner since you can't get it without the pulley.

If I weren't so cheap this would have been a lot easier...! :laugh:

 

[waypoint]

I am more and more convinced it is another bearing/pulley. The sound is just a lot more screachy and rough than a belt sqeak. (But I know sounds can be deceiving in engines.)

Hold off removing the belt again.

With a cheap mechanic's stethoscope ($15 usually) you can probe each pulley at the mounting bolt to listen for the loud grinding. You can also probe the driven accessories: alternator, PS pump, AC compressor. Just pick a stationary part of each, touch the stethoscope probe, and listen.

This is a more precise way to locate noise sources and a very good tool investment.

 

[jfry008]

[MENTION=157795]Swimupstream[/MENTION]

Replacing the various idler pulleys and tensioner pulleys with gates pulleys from rockauto would be a good start imo.

Rockauto discount code: 9157774085518432

 

[Swimupstream]

Thanks [MENTION=172281]waypoint[/MENTION] [MENTION=137652]jfry008[/MENTION].

Was suspecting upper idler 2... took it off cleaned it a bit, screamed like mad when I put it back on for a day or two.

Did the scope thing long ago w the groan, don't know why didn't think of it here. [I have a regular steth (in the medical field) and just use a rod. Gotta be more careful but it works!]

Tonight finally got a moment where I could do it very short window before it was warm and dissipated, will do it again in the morning. But pretty darn sure main volume comes at the tensioner pulley.

BUT... I changed that bearing just 6mos ago (Napa)..., and the sound didn't change when I did it. That's when I got stuck and quit working on it til now. My motorhead nozzleman says, "Then it ain't that pulley. Unless you have something really worn or messed up with the pulley, changing the bearing is 99% of it."

??????
:ballchain:

 

[Swimupstream]

I know I know I know... just do it all and be sure of it. But $ only goes so far, and I've got a few other tasks to address too. (Not to mention life outside of 4R :heh

It's a slow process, b'c once I do something with it, usually gotta wait 'til the next day to hear it in the morning since trucks already warm by the hour I have time to work on it.

 

[kgbagent]

I recommend you order the entire tensioner pulley & bearing via phone with a Toyota dealer (hopefully you can buy this from Toyota without buying the whole assembly with the tensioner). Talking with a Toyota parts guy will ensure you are not throwing parts at your rig based on outdated schematics you find online somewhere.

I'd personally rather replace each pulley/bearing one at a time with factory Toyota parts than replacing all the idlers at once with Gates or other aftermarket stuff.

 

[Swimupstream]

GENIUS tensioner diagnostic

This morn w a second set of ears, loudest defn at tensioner pulley. (was suspecting upper idler 2)

Also got a GENIUS diagnostic to rule out tensioner assembly:

1. VERY VERY carefully place wrench on tensioner (easiest w 2 people so you can set it before turning on. Best at lower R next to battery, away from fan.)
   
2. At idle w no load, torque wrench to R to increase idler tension
   
3. Try at 2 positions. Be VERY careful not to go too fast or too much torque, or the bolt will loosen.

If it gets quieter, problem is belt or tensioner. If it does not, problem is almost surely the pulley/bearing.

Wish I learned this one 6 months ago! No shop or store or anyone mentioned it. Hope this helps someone reading this some day!

(Noise got louder. Buying OEM tensioner pulley tomorrow, thanks [MENTION=75133]kgbagent[/MENTION])

 

[riceandpho]

i just purchase a toyota tensioner from partznet, the cheapest place so far, toyota parts express costed a few dollars more. i dont have noise but i see it moving a little more, im almost at 180k so its time, hopefully water pump still good, no signs of leak, but it was crusted at the weep hole, but not leaking pink. so its normal i guess.

 

[Swimupstream]

NOT the tensioner pulley

NOT the upper idler 2

That is, unless I did a REALLY bad job at putting the pulley in both spots (got the 6203 w the bushing to be able to do both... I know [MENTION=75133]kgbagent[/MENTION]... But went this $49 route ($62-promo code) as a diagnostic before spending the $85 on one OEM.

Buying a new belt tomorrow.

If noise stays, guess that really only leaves the tensioner. If it goes away, wait a few weeks for the belt to break in and see what happens.

 

[Swimupstream]

[MENTION=5149]riceandpho[/MENTION], interested to hear what your outcome is.

I received discouraging advice it may be the water pump or fan clutch too recently. I have NO experience w diagnosing those or hearing what their noises sound like. Also came from someone who had only overheard the conversation and not a lot of detail, so not sure how much to head that.

I also keep thinking about the fact that there is no dust cover on the back of the 6203 (6302 OEM is encased on the back), if that disappeared wout me realizing during previous work... Or if there ever was one, or if the absence of one could lead to noise... Contact or shim distance (though everything appears aligned since t is oem) as [MENTION=75133]kgbagent[/MENTION] is an expert in.

(At this point I think [MENTION=84120]nevada[/MENTION] an [MENTION=172281]waypoint[/MENTION] are rolling their eyes going... Uh, tennnnnsionerrrrrr! As we said....) :dizzy:

 

[waypoint]

(At this point I think [MENTION=84120]nevada[/MENTION] an [MENTION=172281]waypoint[/MENTION] are rolling their eyes going... Uh, tennnnnsionerrrrrr! As we said....) :dizzy:

Nope, just giggling. You're overthinking this big-time.

 

[riceandpho]

[MENTION=5149]riceandpho[/MENTION], interested to hear what your outcome is.

I received discouraging advice it may be the water pump or fan clutch too recently. I have NO experience w diagnosing those or hearing what their noises sound like. Also came from someone who had only overheard the conversation and not a lot of detail, so not sure how much to head that.

I also keep thinking about the fact that there is no dust cover on the back of the 6203 (6302 OEM is encased on the back), if that disappeared wout me realizing during previous work... Or if there ever was one, or if the absence of one could lead to noise... Contact or shim distance (though everything appears aligned since t is oem) as [MENTION=75133]kgbagent[/MENTION] is an expert in.

(At this point I think [MENTION=84120]nevada[/MENTION] an [MENTION=172281]waypoint[/MENTION] are rolling their eyes going... Uh, tennnnnsionerrrrrr! As we said....) :dizzy:

i dont have noise, but if change out the tensioner and got noise, i think its the belt. oem tacoma belt is the same as the 4runner, just cheaper. im using an hd green belt from gates, but i have to run an inch shorter belt due to my high output alternator.