Timing belt issues 02 tundra 2uz-fe

I purchased the tundra initially because the timing kit had been done 7k miles ago and had the shops receipts etc... After about 3k miles no issues I topped off the coolant fluid before a trip. I made it less than a mile and noticed it running rough. After looking behind cam/timing covers I could see the belt had skipped jumped a couple teeth when the crank was at TDC. After tearing into things further I could see the coolant leak and narrowed it down to the shop mechanics mistake as in picture. Belt looked newer and ok. After i purchased a OEM kit from dealer and being verify particular on my work I replaced belt, water pump, hydraulic tensioner, and tensioner assembly as prior receipts showed along with the other idler bearing assembly had been done. Truck ran and sounded better than it ever had when I was done. After another 1k-2k it sounded like the belt had jumped teeth again, sure enough it has.. wondering what I may have missed to cause this... Did the hydraulic tensioner fail, maybe the belt. I also noticed the timing belt guide has more marking and debre than I remember from last time.. open to any ideas or input... ironically I drove it about sixty miles after noticing it running rough so maybe thats what makes the belt look so horrible, better than a broke one though.. also prior to me doing the kit last time all the cylinders had proper compression. thanks all..

 

I’ve done my 01 Sequoia twice and it has the same motor. Never seen that before. The hydraulic tensioner probably did not fail unless you see it leaking. You did pull the pin out of the tensioner after installing correct? All Koyo bearings? Also, the washer in the last pic goes on the crank if I remember right but it has a radius to it and can only go on one way.

 

The way the belt is frayed suggests it's jumping, as if a bearing is failing or not installed correctly, harmnic balancer shit the bed, or something is out of balance in the system and allowing the belt to kick back and forth in its expected track, hence all the nicks and chunks and fraying. I also notice the scoring on the edge of one of the bearings (orange koyo on bank 1) which is a bit suspicious to me! First thing I'd be checking would be spinning and jiggling all bearings and pulleys to make sure they're not loose or noisy. I suppose it could be the tensioner, but I'm suspecting the belt is seeing lateral movement, and I'm not 100% positive a tensioner would cause that - logic being, if there was enough slack to allow that, you'd have jumped time PRONTO.

 

Yes, I did pull the pin, it's the only easy part of whole job... The red bearing or koyo is what the prior owner replaced prior, that is the one I did not replace it seemed ok and had 7K miles on it.. everything else I replaced from Toyota dealer direct. I noticed that koyo bearing scrapes on outside as well and is odd. That one did spin a little hard when I recently removed what is left of belt, should be a sealed bearing and don't think any of the belt debre could effect it, it spun better once I spun it some. Looking back those scrape marks are on it prior but think I should replace it even though I have more time than money no pun intended... Uploaded prior picture of koyo... I also had the timing belt guide with the radius or teeth outwards towards front of truck...

 

Thank you also!

 

Anyone know if that oil pump assembly cover can be changed in case I find anything wrong with it, cracks etc.. I read the engine has to be pulled to change the oil pump but wasn't sure if that was all part of the cover. Haven't looked deeply at it yet but reaching and thinking the worst. No oil anywhere so that's good.. thanks

 

I guess I can't say for certain but, I'd bet a pile of cash this was put on incorrectly. It should be installed concave face towards the radiator. Being that the radiator side of the belt is chewed up, it looks to me like the it was installed concave face towards the engine. The teeth on the disc would chew up the belt like that as well as possibly grab the belt and skip a tooth. Do you recall it's orientation when you took it off?

 

1. Hi, I do remember I had it on as it should be with teeth closest towards radiator. I know the picture is hard to see that but the marking on the timing gear guide indicate that as well. Uploaded some better pictures of it as well, still hard to see though.. I wish it was that easy, I'd be the first to admit my error.
2. I'm questioning that red idler Koyo bearing, maybe heating up, I see it in the kit that the prior owners shop receipts shows it but doesn't mean it was replaced. The scrapes on it are odd. I don't see anything around it that it would have rubbed on and it was scrapped before in picture the first time I opened everything up. I just assumed the first time it jumped timing it was from that coolant leaking and everything being soaked but maybe a second issues with that bearing.. thanks all

 

That being the case I would think that something (i.e. either the idler or tensioner) is operating at an angle and forcing the belt towards the angle sensor plate. At least something in the loop is forcing the belt forward, and those would be my suspects.

 

With that kind of wear I would suspect a bearing in one of the idlers to be at fault

but that’s a weird one if it’s all oem parts, I have seen the eBay “oem” parts do this. Never a factory one

 

I agree, wondering if the belt didn't simply fail on the outer side more than the inner and just keep walking towards the outside as it broke down more and more.. thanks for everyone's input if I find anything definite will post back. Thanks

 

Does the crank shaft pulley look original?

 

I hadn't really looked at it closely, any specific markings to look for? I can take a look later today..

 

Hello empty lord, when you state you've seen the ebay "oem" parts do this are you referring to the timing belt, bearing or both. The red koyo bearing with the scrapes on it I don't know the history. The prior owner/shop that I have receipt for used this timing kit part number 20394K. I replaced all of that as mentioned with exception of red koyo idler pulley in question. I've just never seen a timing belt look like that in any of my various vehicles over many years..

 

I suspect he's referring to pulleys/bearings, but more in the context of: There are a shitload of people selling "OEM" (knockoff) parts on fleaBay, scAmazon and similar sales outlets which don't make any effort to authenticate their parts or validate their supply chain. i.e. When you order from those outlets, you have no way to know if you're getting real parts, and counterfeiting is such a huge problem with it that we're trying, at the nat'l/federal level, to pass any kind of legislation that has serious teeth to punish the vendors. The reality is, authorities can sieze properties where drugs are being sold if the owner knows illegal activity is happening but does nothing; when it comes to big business like scAmazon/Temu/Alibaba, nothing similar exists, so they have no incentive to protect consumers.

 

I totally agree and understand that, too much at risk or stake to risk it in my opinion. The crankshaft pulley looks original from what I can compare to what I've seen over the years. Doesn't look damaged or anything, when I had it in time or running, you could hardly tell engine was running, no shakes or vibrations when sitting in vehicle or wabble etc... Thanks

 

Are you saying the Koyo bearing is scraping against the timing cover?

 

Other than the idler bearing being bad, the only other thing I can think of that would cause the belt to wander off is the washer behind the tensioner... is it there? is it flat? are the mating surfaces clean? This is assuming the water pump and tensioner are new OEM or AISIN.

FYI - The timing belt kit that was installed by the previous owner was an O'Reillys kit.

 

I don't see any sign of rubbing on the timing cover. Whatever happened to that bearing happened prior to my ownership I believe.
The tensioner assembly and bearing is new oem direct from dealer as is the hydraulic tensioner. I was looking last night at the washer that is behind the tensioner assembly, it the washer isn't new and noticed when torquing to specs I don't believe it moves as freaky as it should meaning the whole assembly, not the bearing.. the washer side that's up against the tensioner assembly is rusted, pitted a bit and has a slight depression, other side towards engine has machining marks on it yet. If I loosen the bolt up a bit under torque it moves better.. I don't remember what I torqued it at last time but used this chart last night and was using the reference of 26 and not seeing a separate number for each idler bearings? I don't remember looking at washer last time. Sounds like a good place to start by replacing that washer and am also ordering that other idler bearing oem. Initially dealer said that bearing never fails so I didn't order it originally, that and it was supposedly replaced prior to my ownership with 7k on it..thanks again..

 

Looks like both the tensioner bolt and idler bolt are torqued to 25 ftlb per the FSM. I don't think the values you used are for the 2UZ.

 

I honestly don't remember what I torqued it was almost a year ago but I do remember using the loc-tite. Once the torque is done properly how freely should the assembly pivot prior to tensioner being installed.. the washer was a great point! Thanks

 

You should have a copy of the factory service manual (FSM) for your year range. You know where to find it on this forum right? (Hint: 5th line, here, download it to your PC, may not last forever).

Never trust the internet for torque specs. But also be skeptical, we know of at least one typo in the FSM related to torque specs on the lower ball joints. Which you must also use OEM parts when replacing, unless you like your truck being totally fucked.

Follow the book, generated by the people who manufactured the motor.

 

Thank you for all the info everyone. I double checked all the prior oem dealer parts I had ordered prior and everything checked out again against VIN.. I have just placed the order for a timing belt, belt idler (one in question), shaft for tensioner belt idler assembly (just to be safe) and washer plate. Thanks for the FSM link..

 

Post pics and ask questions as you go.

 

Will do!
For reference the washer pictures..

 

I received my dealer parts and after unboxing the oem Toyota idler bearing I noticed similar scratches marks etc and saw others out on the web noticed this also but they didn't purchase them directly from dealer like I. Here is a picture side by side for reference..

 

I also did some comparison with idler assembly and torqued it with old washer and bolt and new washer and bolt lastly. When torquing the old setup to the fsm recommended 25 ft lbs it was difficult to move the idler assembly arm back and forth where the new bolt and washer I could easily move it with my index finger and thumb. I'm surprised the hydraulic tensioner wasn't taking up adjustment with it. I'm guessing as someone mentioned the washer and the lag of the belt wasn't being taken up properly after wear in... I don't have high speed internet at the place I'm doing this project but posting these pics as I go, ignore the missing nuts, bolts in pictures as I'm getting in-between as I peck away.. I also replaced the idler bearing as mentioned in prior posts... Be gentle on the constructive criticism...

 

Hindsight I probably should have taken picture of idler assembly after I rolled the engine over a few times so the belt was aligned a bit better, it looks a little out of wack on idler bearing assembly but wanted to show all the timing marks on or should have taken a picture after...

 

Up and running again and back to sounding normal, no engine codes. Going to take a look at things down the road a bit and see if I can see any wear on the belt... Thanks again for everyone's input and assistance..

 

Congrats dude, I know this must have you feeling relieved. Friendly reminder: Make sure you routed your crank position wire clear of danger. I see no evidence to the contrary, but ... nudge nudge.