2003 Tundra 4.7 timing belt gone wrong

I went from the highest of highs to the lowest of lows. Maybe I'm just tired. I am doing a timing belt replacement on my 2003 4.7liter Tundra with 135k on it. Every thing went textbook until I rotated the newly installed belt. It is a Mitsuboshi belt that came in an Aisin kit. It came with nearly everything but the new radiator hoses. Belt went on fairly easy and I thought correctly.

I don't think anything moved but I guess the crank could have.

 

I still haven’t done mine yet in my Sequoia. Just to make sure, you didn’t rotate it with the belt off correct? If you didn’t it should be OK you may just need to rotate the engine again to see if those marks will lineup. I could be wrong it’s just what I have come to the conclusion of myself.

Line up the marks, remove old belt, install new belt. If this is what you did it should be OK. It looks like you may have rotated it once the new belt was installed, to see if it was still good?

 

I put the crank pully back on temporarily for visual simplicity. It rotates by hand well...no noticeable contact. Has anyone seen something like this before? I don't see how it's possible for it to be that far off. Wondering/hoping I got the wrong belt. I'm stuck driving our extra 99 corolla until I get this back on the road. Any ideas?

 

Oh I see. Your upper marks are lined up but the crank isn't. Hmm

 

Literally every time I put the crank at TDC the cam marks come up at a different place

 

Did you have the crank at top dead center when you installed the belt as well as the cams lined up? I’m hoping you did as that sounds like it could throw everything off once you rotate it.

 

No I did it at the T's on the cams. I was under the impression that was the correct way.

 

its funny the Mitsuboshi box says TB298M and the belt says CD298. Doesn't seem right but I'm not sure. Got it from volkstoy off ebay quite a while ago.


looks like they are supposed to be the same

Wishing now I had marked my old belt before I took it off.

 

The cam shafts rotate once for every two turns of the crankshaft, the cam marks should line up on every other rotation of the crank. good luck, john

 

Thanks. I'm going to sleep on it and start fresh this weekend. Getting tired and I'm apt to do something stupid....making it worse. I may grab another timing belt. I never bothered to size up new to old. It was all lined up once and no matter how many times I turn the crank over it won't line up again. It looks like I must have moved the crank. It was a major PITA to get the bolt out so it is certainly possible. Maybe fresh eyes and mind will improve my perspective.

 

@ColoradoTJ

Can you please move this to the first gen section so we can get this guy some help?

 

The cams should be lined up to the marks not the ts. Common mistake. Don’t start the engine.

Line the crank up then get the cams lined up to the straight line marked to the left of the t.
After that’s all done set the tensioner and turn the engine 2 revolutions and the lines on the gears will line up. The marks on the belt won’t. That’s normal.

 

I’ll get the instructions from
Tis when I get to my computer and post them for you.

 

https://cdn.discordapp.com/attachme.../547621161417048064/03_tundra_timing_belt.pdf

 

Based on the first set of pics I think you have it properly installed. Install the tensioner and pull the pin if you have not already done so to prevent the belt from jumping a tooth while test rotating it. Spin the crank till damper indicates "0" and both cam gear indicators will align under the "I" hash marks at 0 degrees TDC every other rotation as previously posted. Don't worry about Lcam and Rcam on the belt anymore as they move along the belt with each rotation due to crank gear being smaller diameter than the cam gear. Somebody did the math based on gear teeth and total belt teeth and I think it was something like 192 rotations and Lcam and Rcam will align with the gear marks.

Rotate it over and over 2x, 8x, 16x, and it will always show under the "I", not the "T" at TDC. Then begin reassembly. Good luck.

 

Thanks a bunch. I was looking for that...
I watched a Toyota mechanic on you tube doing it and it showed him setting it to the T's but it was probably 3 hours squeezed down to 12 minutes with no audio so I may have missed some things. I'll give it a go this weekend. I appreciate the assistance. This was on my must do list and I told myself it has to get done before the Kenwood stereo and backup camera sitting on my passenger seat.

 

@remington351
I thought I was golden until I rotated it. If I line it back up with the T's I'm 2 teeth off on the crank. I'm not sure when but it has to have jumped. If I line up with the dashes it is considerably off from the 0. A good nights rest will help my thought process in the matter. I appreciate everyone's help. Truck was driving like it was in 2003 before I started working on it.

 

at least you asked! lol ive had to replace a few of these engine because someone did their own t-belts. almost every single one was because they lined it up with the Ts, not the dashes (these are the VVTI engines im talking about. i dont remember if yours is interference, but oldest ive had to replace was an 05)

 

Start slow. Take pics. The good thing is nothing is hitting, so I think you are there. If the tensioner was out, then the belt may have jumped teeth when you rotated the crank. But based on pics above, I think you're installed correctly. T's are used to set belt then forget about them. The pics show the damper lined up with the white dot that is used in conjunction with the T's. The hash mark for the passenger gear is at about 6 o'clock position. Cams move 1/2 rotation for full rotation of crank, give or take a couple teeth. White dot pin is 50 degrees past TDC. So when you bring the crank around the last 310 degrees to TDC, you will bring the passenger cam from 6 o'clock to about 12 o'clock position, which will be right under the "I", not the "T".

We don't care about the T anymore. We don't care about Lcam Rcam or any other paint marks on the belt. All we care about now is damper at "0" TDC (make sure woodruff key on crank did not fall out) and hash mark on passenger cam gear under "I" and dimple on driver cam gear under "I" . If belt didn't jump all will align. Rotate a bunch more times to make sure then reassemble. Good luck.

 

Yes, it's a interference engine, if the cams are not lined up right you will break parts!

 

@empty_lord
@remington351
Thank you Thank you Thank you
It was dead on from the get go. I incorrectly thought I continued to line up the marks on the belt. After rereading @empty_lord and @remington351 posts it sank in that the belt marks are install only. I had it in my mind that belt marks should line up every other rotation. Now every 2 revolutions the tics on the cam gears line up with dash marks while the damper is on 0. If you ever find yourselves in Kansas City I owe you a beer. Now as long as the water pump seals up I'm back to being golden. This weekend I'll button it back up and turn the key. Be driving the Tundra to work next week

Picked up a couple of the coolant bypass hoses from the Toyota dealer today since they were original and I had them off. Sat in a 2019 Platinum they had in the showroom. That thing seemed massive compared to the 2003. Price as well...48k

Thanks to all for the assistance. You are awesome.

 

Good to hear it’s all good

 

Glad to hear it. Good luck with the rest of the repair.