Timing belt replacement mistake Please help

High so I have a 06 tundra 4.7 V8 interference motor. While putting on a new timing belt after setting to top dead center. The left Cam or driver side rotated counter clockwise, I believe. The cam moved when i was pulling on the belt trying to stretch it over the other cam. how do I get the timing back to TDC without messing up the motor? I have read previous post about this but I have not found a real good description on what to do. I am nervous that I may have messed up the motor already.

 

Welcome Ryan!

 

Hay SR5TRDTUNDRA thanks.

 

Sorry couldn’t help you out. I’m sure someone will chime in soon.

 

thank SR5TRDTUNDRA. no I have not started the motor. the new timing Belt is not even put on yet. It might help to mention that the timing mark is not that far off Just a few teeth. I tried rotating it by hand once WITHOUT a wrench. I can get it back to tdc but then it just flicks right back to where it is now. I realize I can remove the spark plugs and reduce the compression which may cause it to stay at tdc. But I don't even know if moving the cam by itself is a good idea right now. There has to be a protocol to this problem?

 

I'm not looking up to doing this job please keep use updated. Take your time and make shire everything is right.

 

Watching

 

Not that uncommon for a cam to move. It's not compression that does it its the tension from the valve springs. Just use a wrench or breaker bar and socket to hold it as you put belt back on. As long as you don't have to force it you won't hurt it. Make sure to rotate engine a few times around and check your marks again

 

Contact @LOTSOFTOYS and ask for his opinion. He works at a dealer in Denver.

John

 

This... When I did mine it took several tries to get it on with all the timing marks correct. Try, try and try again, it can be a pain since at TDC it's finely balanced between a couple of the valve springs.

Having someone to help hold one cam is useful too

 

Agree with tomsinamerica, just try and try again to get it lined up. Might want to turn the cam a little past TDC so it does not spin back while putting the belt on. Align to the belt as you slip it on.
Turning the cam belt a little doesnt hurt anything.
For future reference its easier to turn the engine 15 degrees past TDC. Cam sprockets should align with the "T" and not the "l". This puts the cam past the tension caused by TDC and is much less likely to turn by itself when the belt is off. Your FSM should have mentioned the 15 degree part.

 

oK thanks so much for the information!!! I'll post photos when I'm done. I hope this will help someone else not have this problem or be able to solve it if they do.

 

I used a clamp with smooth surfaces to hold the belt to the cam gear once aligned to the cams and then thread the belt onto the rest of the pulleys, etc. Like they said before, use a wrench and get the cam aligned with the mark and slip the belt on and clamp it in place.

 

Also, I always have the plugs removed to make it much easier to rotate the engine by hand. This is not part of your issue but it just makes positioning easier. I replaced the timing belt twice on my 2006 4.7L and I just took my time and followed the manual instructions to the letter.

Dan

 

Thank you mnm and bergman. I just was really worried about bending the valves why I move the Driver side cam. Also worried about the valve getting bent when the Cam moved on it's own. The picture shows my timing top dead center and my Cam mark in blue. So you can see how far it moved.

 

If the belt isn't attached to both cams AND the crank at the same time, the bottom end can't move and the pistons won't hit the valves just by turning the cam(s). You will be fine, just make sure it's all lined up proper before starting the truck. Triple check and turn it over by hand multiple times, verifying the index marks before you button it up.

 

Thank you rocky mtn!! You guys have been so awesome answering this questions for me!!!! I really appreciate everyone's time thanks again.

 

It actually takes a lot to bend valves in a 2UZ-FE. Had a Tundra come in a few years back, running, two teeth off on the cam's on both sides. Ran, quiet, just had misfire codes and no power. I retimed it, ran like a new truck. You have to be going down the interstate at a good speed and have the belt break to tear things up. That's per a few techs I work with. We've seen a lot of the V8 engine's come in out of time. Cam's every which way. Re-time it, runs great.

 

Thanks mudslingers 79!!! You know I don't do these jobs because I enjoy mechanics, although I do. I don't do them to save money. I do them to learn. learn how my vehicle works learn what the parts are and how to fix it. Everyone's reply here has really taught me something more about the truck. So thanks again for your time and input.

 

OP how hard would you say the job is? Any complex areas other then the timing marks?

 

You know the jobs not hard 1aauto has a great video on it. There's 3 parts to the video. Link is only for part 2 but you'll be able to find the other parts. In fact I rotated that 1 cam by hand took my time and the timing belt slid right on. I labeled all my parts In numeric order. also tape all boats to the parts using painter's tape. A little anal but super easy to put back together. When I get done I will make a tutorial with torque specs.

Watch "How To Replace Toyota Tundra Timing Belt 2002 V8 Disassemble Front of Engine PART 2 1AAuto.com" on YouTube
https://youtu.be/fM1A0DWhRHc

 

When I do them I take everything apart in a specific order and lay it out, bolts with specific parts, on my tool table and tool box. I just reverse for install. Makes it really.

 

You are just fine, it happens all the time, try doing a timing belt with 4 cams, this is the easiest one I have ever done. There's a tool to hold the cam.....there's a tool for everything, but at the moment you don't have it, use the big paper clips, those monster black ones with the 2 handles on them, not the typical little paper clips. Someone else mentioned this, and it works. Just make sure all timing marks match up, and most important, spin it around by hand a few revolutions, and make sure those timing marks line up. If it is one tooth off it can still run, but will ping going up a hill or heavy load and might throw a check engine light. I can hear a wrong timing belt job driving down the road.

 

Z32, now that's a fun job....now twist the engine sideways like the Mitsu 3000gt. Engineers are not looking out for the mechanic. ZCON 2018 in Atlanta this year.

 

I have enough nuts and bolts to probably fill the back of my truck...........from parting up about 15 Z cars over the last 12 years. (1970-1983 only) I love that Z32tt......but I'll have to find the pick of the one that couldn't follow me around the corner in my 240z at the Canadian Raceway. He was towed away from the track. Probably totaled. We all felt bad for the car................oh the driver too.

 

I just wanted to reply. I did get the timing belt done and everything went great!! thanks for all your Support and help!!!

 

I did a timing belt on one yesterday at work made me think of your post. The cams always move. But good news your back on the road, it's not the easiest timing belt job.

 

I'm resurrecting this thread to make sure I understand why the procedure recommend in this thread differs from others, and even the instructions and service manuals that I've seen online. I'm going to attempt my first belt change on my 2006 Doublecab in the next few weeks.

My approach, in order, once everything has been removed to uncover the belt would be as follows:

Step 1 - with original belt undisturbed, rotate crank clockwise by hand until the cam indicators line up with the TDC hash "I" mark on the block. Drivers side cam has a dimple, passenger side has a small stamp/v cut.

Step 2 - confirm the crank balancer timing mark shows "0" aka TDC, and crank timing sprocket dimple lines up.

Step 2.5 - the purpose of above steps is to confirm the engine is properly timed, the belt has not jumped, nor has a prior replacement belt been installed incorrectly.

Step 3 - now turn the motor, with original belt attached, clockwise until the cam indicators align with the embossed "T". The purpose of this as explained in this thread and echoed on some posts a 4runners and Toyotaheadquarters, is to position the cam such that when removing the belt, the valve spring pressure will be less likely to cause the cam to shift as happened to the original poster of this thread, correct?

Step 4 - replace needed parts and belt. Make sure the R-cam L-cam marks on the belt align in the exact tooth/groove of the old belt. This is to ensure there is no slack or kinking of the belt that could cause it to jump when in service

Step 5 - rotate crank by hand back to TDC and confirm cam is in alignment under the "I" hash mark, not under the "T" when the crank is showing "0". The timing belt crank mark should align with crank sprocket dimple. Repeat step 5 a couple of times to make sure the belt is meshing properly with all sprockets.

Step 6 - reassemble all other components.

*if alignment is not achieved in steps 4 or 5, or if the cam(s) shift, upon taking off the belt, simple rotate the cams by hand, clockwise only, to align cam indicators with the "T". Then install and repeat step 5 until satisfied*

I'm not telling people this is what to do and why it's done. I'm saying this is how I've logic'd the procedure in my own brain and I'm asking all of you with more experience to let me know my thought process is correct.

Thanks.