Timing belt related noise? (two years after TB job)

[[email protected]]

Hey guys,
I've been chasing down a new noise on the 01 4Runner the last few months.
This is not my daily driver so I have been slowly tinkering with it.

The vehicle has 196kish miles and I did the timing belt, water pump and all the associated parts with this OEM kit (screenshot attached) about 2 years and 8k miles ago.

The noise started a few months and 500ish miles ago.
I went ahead and replaced the original factory alternator and AC Idler pulley as i thought it could be the source of the sound.
(Bought factory toyota parts from the dealer)
At this point, I ran the vehicle today without any aux belts or fan mount attached and the sound is still present.
I have tried tracking it down with a mechanic stethoscope and a big solid steel rod and it seems the loudest on the tensioner roller and the timing idler roller between the two cam pulleys.

It is definitely a lot louder with the timing cover off and really seems to be on the front of the engine and not valve train related but I could be wrong.
I did check valve clearances when I replaced the VC gaskets a few years back and everything was within spec.

I have not taken the Crank pulley/Harmonic balancer off yet, but did pull out the TB tensioner and partially moved the belt to see if I could find any play in the tensioner roller, idler roller and water pump. All of them seem to spin freely and quietly. The TB tensioner roller, has a slight front to back play but I cant tell if its bearing related or simply because its on that hinged mount to allow the tensioner to work.
(I'll know more when I get some long enough bolts to pull the crank pulley and last timing cover off.)

The reason Im posting these videos and reaching out for your help is because im concerned Ill get it all apart and still not know the source of the noise.

Posting a link to a shared folder that has several videos, if you have time to check some out and lend some advice; it is greatly appreciated!

All belts and covers, fully assembled (March 2024)-
Timing Cover off (June 2024)-
Timing cover, aux belts, fan mount, etc. removed ( 4Runner Noise 4 June 2024)-

Google Drive Folder of 4Runner Noise Videos

 

[beingnotdoing]

I bought the same or similar kit that came highly recommended when completing my timing belt job. 3 years later, the timing belt failed while driving at 70 mph down the highway. I am not a sufficiently good mechanic to figure out whether it was a part failure or installer error (me).

However, I can confirm that the 3.4 liter is a non-interference engine. When my timing belt broke, the engine simply stopped running and I pulled over to the side of the highway. When installing the new timing belt kit, it seemed to me that the number two idler pulley was a little wonky, but I can't be sure if that is what caused the failure.I did not have any noticeable warning prior to my belt breaking.

I don't know if my limited experience can help you, but I wish you luck with your fix.

 

[Endlessblockades]

I don't have any constructive advice, but hopefully some more experienced members will check out your 4 videos. There are a lot of noises there - is it the semi-intermittent metallic clang that is the concern or one of the constant clicking noises? Video #4 without the timing cover will probably be helpful to someone here. That's a damn clean engine1

 

[3bears]

looks like a quality kit, i cant figure out your noise

 

[2TH4IST]

Thanks for the vids. Hmm that sound, sounds very metallic. Does the sound get louder with rpm change? At the same time it kind of sounds like a squeaking belt. Like the teeth of the timing belt gripping the sprockets.

I would pull the timing belt off and do a recheck of the idler and tensioner and waterpump.

Silly question, did you put the little convex washer on the crank sprocket? It keeps the tb from walking off the crank sprocket.

 

[[email protected]]

I bought the same or similar kit that came highly recommended when completing my timing belt job. 3 years later, the timing belt failed while driving at 70 mph down the highway. I am not a sufficiently good mechanic to figure out whether it was a part failure or installer error (me).

However, I can confirm that the 3.4 liter is a non-interference engine. When my timing belt broke, the engine simply stopped running and I pulled over to the side of the highway. When installing the new timing belt kit, it seemed to me that the number two idler pulley was a little wonky, but I can't be sure if that is what caused the failure.I did not have any noticeable warning prior to my belt breaking.

I don't know if my limited experience can help you, but I wish you luck with your fix.

Wow, sorry to hear about the TB failure.
Glad you were able to pull off the road without any more damage.

I don't have any constructive advice, but hopefully some more experienced members will check out your 4 videos. There are a lot of noises there - is it the semi-intermittent metallic clang that is the concern or one of the constant clicking noises? Video #4 without the timing cover will probably be helpful to someone here. That's a damn clean engine1

I'd like to address any noise that is out of the ordinary, I dont have a good ear for this stuff so your comments are helpful. With the stethoscope I think i understand the normal valve/injector tap/click sounds but this metallic sound is the cause for my concern.

Thanks for the vids. Hmm that sound, sounds very metallic. Does the sound get louder with rpm change? At the same time it kind of sounds like a squeaking belt. Like the teeth of the timing belt gripping the sprockets.

I would pull the timing belt off and do a recheck of the idler and tensioner and waterpump.

Silly question, did you put the little convex washer on the crank sprocket? It keeps the tb from walking off the crank sprocket.

Thanks for your help, I posted another video that has some engine rev and it does sound like it increase with RPM's.

I also posted a video with the timing belt tensioner off and spinning the idlers and may have some front to back play in the tensioner idler or whatever that one is called but its hard to tell, they all spin freely and feel really solid.

As far as that convex washer, its hard to remember but I think its on there,
The top picture is from today with slack on the belt.
I found a few pictures from back in 2021 when I stripped everything down.

 

[Ibrad]

I listened to the videos. I'm guessing a bad water pump. With turning bearings without tension, noises can be hard to hear or get to appear.

 

[phattyduck]

The vehicle has 196kish miles and I did the timing belt, water pump and all the associated parts with this OEM kit (screenshot attached) about 2 years and 8k miles ago.

Those are all quality parts IF (giant IF) those are actually what you got. Most, if not all of those parts listed have crappy knock-offs that could have been substituted. What was the source of the kit?

-Charlie

 

[[email protected]]

Those are all quality parts IF (giant IF) those are actually what you got. Most, if not all of those parts listed have crappy knock-offs that could have been substituted. What was the source of the kit?

-Charlie

Hey Charlie,
I bought this kit from aircabinman on eBay. (Screenshot of the listing attached)
I think it was recommended on this forum, not to say the parts are guaranteed but I remember several factory looking Toyota box’s.

I’m going to grab some m8x1.25x100mm bolts tomorrow for a 2x4 crank pulley holder and pull some more parts off to see if I can find anything that stands out.

I’d hate to buy parts just to put it back together and still have the noise.

 

[Endlessblockades]

A highly reviewed kit that many people recommend. I should probably get one to have on hand.

 

[[email protected]]

Finally got around to working on this again.

When I pulled off the water pump I noticed a shiny section on the block and was wondering if you guys thought this could be the water pump “blades?” making contact with the block?

I’ll look around for pictures of other people engines here to see if they have similar wear marks.

 

[[email protected]]

This picture may be a little more clear.
Thinking this is abnormal-

 

[2TH4IST]

It's possible that the blades could have contacted the block, does the water pump blades have any damage to them? But I figure if the blads wobble that much you would be able to feel it in the pulley. That could of happened when you were cleaning the gasket surface too.

 

[[email protected]]

Thanks for the response 2TH4IST,
The water pump blades dont appear to have any damage.
Good thought on previous damage from when I was cleaning that area a few years back. I can't remember if I had scrubbed that down and possibly scuffed it up.
I didnt accomplish much this morning, I still have a 2x4 that I had used to hold the crank pulley but I picked up some m8x1.25 x 90mm bolts but they arent quite long enough. No clue what I did with the original set.
I hope to pick some up this week so I can get the last timing cover off and hopefully find something that was clearly causing the noise.
Thanks guys!

 

[mtbtim]

I listened to the videos and I agree it's a metallic sound. You ruled out the pulleys at the front of the engine which was good. If it's not one of the timing belt idler pulleys or the water pump pulley, you have a much bigger problem on your hands. If it were me, I'd contact the aircabinman Ebay seller and ask if he'd sell you just the idlers and the water pump and replace them. It is throwing parts at the problem, but since you can't narrow down the source, I think this is money well-spent to find out if you actually have a major internal issue with your engine. If the idler pulley and water pump replacement works to get rid of the noise, maybe aircabinman will refund you the cost of the parts for all the extra work you had to perform due to the faulty part he provided. His kits have been used by hundreds if not thousands of people and the reviews are usually very positive. I think he'll want to maintain the positive image he has in the Toyota Community. My Timmy the Toolman videos have probably sold tons of his kits.

 

[[email protected]]

I listened to the videos and I agree it's a metallic sound. You ruled out the pulleys at the front of the engine which was good. If it's not one of the timing belt idler pulleys or the water pump pulley, you have a much bigger problem on your hands. If it were me, I'd contact the aircabinman Ebay seller and ask if he'd sell you just the idlers and the water pump and replace them. It is throwing parts at the problem, but since you can't narrow down the source, I think this is money well-spent to find out if you actually have a major internal issue with your engine. If the idler pulley and water pump replacement works to get rid of the noise, maybe aircabinman will refund you the cost of the parts for all the extra work you had to perform due to the faulty part he provided. His kits have been used by hundreds if not thousands of people and the reviews are usually very positive. I think he'll want to maintain the positive image he has in the Toyota Community. My Timmy the Toolman videos have probably sold tons of his kits.

Thanks Tim for the feedback.
Your videos motivated me to start learning how to work on the 4runner in the first place.
I pulled the bottom timing cover off and the tensioner roller.
There is some bearing noise on this tensioner roller bearing. (or whatever the proper name is for this guy)
I added yet another video incase someone has the time to check it out.
4Runner Noise Folder

I did reach out to aircabinman and he responded promptly but differed the automotive questions to professionals.
I may just grab this tensioner roller and throw it all back together.

 

[[email protected]]

After giving this some more thought, I’m going to follow Tim’s advice and go ahead and grab a water pump and both idlers.

If anyone else has any other thoughts, please let me know.

Thanks guys!

 

[DK327]

I just watched the videos in your Google Drive; is it me or does the passenger side camshaft pulley looks like it's wobbling a bit compared to the driver side?

 

[2TH4IST]

Yeah that bearing doesn't sound to healthy. Do the idler tensioner roller and w/p and see what happens. Before you put everything back together run it to confirm noise has gone away.

 

[Previologist]

I have little expertise but excellent ears, and my ears keep pointing to the water pump. Even before I saw the picture of those scrapes I thought it sounded like those clinky water pump blades.

I could be way off though.