the rear cam sprocket might rotate a little during step 3

That is true. When you loosen the tensioner hold the rear sprocket with a bit of tension so it does not suddenly "fly"and scare you , like it did me.
For the rear sprocket/belt mark alignment I used a mirror to ensure proper alignment. The timing belt will have marks on them . If at first they don't align rotate turn the belt around. Dont' forget the washer on the tensioner pulley, i believe that is where it was.
After the final alignment of the marks and releasing the tensioner "canister"should you rotate the engine any , the marks will not line up till after many revolutions . like 24 or so IIRC.

 

This:

2. rotate crankshaft 60 degree BTDC, counter-clock wise

...Is so a cam doesn't spring back resulting in the valves hitting the pistons. There's not a whole lot of energy there but better safe than sorry. The cams barely moved when I released the tensioner.

Do yourself a favor and remove the wiper assembly and cowl so you can see that back cam dot straight on. It's well worth the 20 minutes of extra work to know for sure that the back cam is timed correctly, the first time. Professional mechanics who've done the job many times don't need to but if I had to do it again I'd remove the cowl. I was so unsure if I got that cam timed right that I put the harmonic balancer back on without the timing covers or accessory belts installed then started and ran the engine for a couple of minutes just to make sure a P0016 or P0018 CEL didn't pop. I've read that one will pop within a minute if a cam is out of time.

 

Do yourself a favor and remove the wiper assembly and cowl so you can see that back cam dot straight on. It's well worth the 20 minutes of extra work to know for sure that the back cam is timed correctly, the first time

That is a solid suggestion from Roader. I did this as well. Just be careful how you use your tools along the edge of the lower part of the windshield. Ask me how I know! I cracked mine and had to replace it!

 

I am here to cheer for you guys who DIY the timing belt!

 

When I did mine back in 2018 it was the first time ever on a V6. It is a piece of cake on my 4cyl Volvo. However I gained confidence watching numerous videos for the Sienna. I even bought tools to do the job. I got to tell you though , that it was a tense moment after buttoning things up and turning the key to start. All was good. Pat on the shoulder!!

 

I'd suggest using a paint marker to put a line across the belt and each pulley before removing the belt.
Then lay the old belt next to the new one and copy the marks to the new belt. You may need to count the number of cogs on the belt between marks. This is a good way to double check everything.

 

Then lay the old belt next to the new one and copy the marks to the new belt.

That is a great suggestion! Sometimes though the new belt has markings on them but your suggestion is failproof.

 

You can use a locking pliers on the socket , turn clockwise ( tighten) and that should work in getting the tool off. You can try a regular pliers too!

 

Buy a good set of sockets instead of an electric driver. You should have a 10mm socket with 1/4", 3/8" and possibly 1/2" drives.

You should also have ratchets with long handles which gives additional leverage. I like the ones that swivel, which helps in tight locations.
Something like this:

1/2 in. Drive Professional Long Reach Flex Head Ratchet with Comfort Grip

Also, you might have better luck using a combination wrench instead of a ratchet in that situation. Ratcheting ones would be even better...

 

used a locking pliers to tighten the bolt back up then used a open wrench from underneath to remove it. Thanks to Paul.

now t-belt cover is off but the belt looks pretty new?! is the original belt supposed to say misoboshi or toyota or made in japan anything like that? Not seeing anything like that from the top side. My relative got the vehicle with 80k on it two years ago, he didn't do t-belt and I assumed previous owners didn't do it.

No t-belt maintenance label on the cover. lots of oil stain around the bottom of the cover though.

PS, the white things on the t-belt is just little dirty dust from my gloves. Vehicle has 95k and is a 2004

 

As I recall (it was almost five years ago) there were no markings on the old timing belt from my '04 and I know for a fact that it was the original belt from the factory. It too looked fine with 145K miles but looking fine doesn't mean it won't break with age.

That's not a small amount of oil. Find and fix that leak. You don't want it getting on your new timing belt.

 

time to remove the dreaded crank bolt. darn thing wont budge. current setup: holder tool from amazon, 20 inch extension, 4 ft pipe added to breaker bar for leverage. And yes, I did spray some pb blaster on it everyday in the past 3 days.

wanted to try the starter bump method (will remove EFI fuses first) but didn't find any good spot to brace the breaker bar without using an extension.

might have to bite bullet and get the lisle high mass socket after all.

 

darn thing wont budge

Had the same problem with my 99. As a last resort I drilled a bunch of small holes thru the washer under the bolt head. This weakened the washer so the bolt came out. Replaced the washer.

 

Smack that bolt with a sledge hammer, hard. I have a small 6lb hammer that did the trick but any sledge will do if you can aim it without hitting anything else.

That's why impact wrenches work, they impact the bolt in addition to turning it. That bolt's been in there for almost 20 years and it's set in its ways. Smack it then use your four-foot pipe on the breaker bar. It'll come out.

 

I dont have a sledge hammer, so used a regular hammer instead, so far no luck...
Also, kind of hard to swing a hammer inside the wheel well.

 

You are using the correct setup for the crank bolt.
I have (carefully) stood on the end of a six foot cheater bar to break these loose. I weigh around 150 lbs, so that is around 900 ft lbs of torque.
Make sure you have a good breaker bar and a high quality six-point socket

 

I would strongly discourage using the starter bump method. You don't want to add a new flywheel to your timing belt project.

 

I gave up, had the van towed to my mech and made it his problem.



JK!

bit the bullet and handed money to Amazon for a Lisle socket last night. Should get it in a few days...

 

had the van towed to my mech and made it his problem.

gravy for him....and you were sooo close

 

I have done a couple of these. I feel your pain doing it in the driveway.

Sometimes that bolt needs some heat.

 

I got it!!! I think the trick is to keep hitting it, not using bursts. I kept at it for like 30, 40 seconds and it finally started turning. what a feeling.

question: I have the front of the vehicle on stands since last week, passenger side wheel has been removed, of course, but driver side wheel is still on and tire is somewhat resting on the ground. Is this OK? will it put too much stress on the suspension? Given the rate of my progress so far, I think it'll be at least a few more weekends of work (I might as well do the rear valve cover gasket while I'm at it).

 

harmonic balancer off, everything behind the t-belt cover is covered with oil, can I use Engine Brite (degreaser) to clean it off or should I use break cleaner.

picked up cam and crank seals from dealer and some tools from HF.

 

Not sure about the cleaning, but props to you for sticking with a difficult job! I did this job on mine when I first purchased it. It took me a good week too and by the end my jack stands had sunk four little indentations in my driveway! It’s a tough one, but you’ll get there.

 

Thanks for the kind words, I'm still enjoying the learning process although the job can be frustrating at times.

Right now, I'm "stuck" (pun intended) with the 2nd tensioner bolt (yellow arrow) behind the power steering pulley bracket. I dont see how I can remove it without taking the bracket off which won't go any lower because it's being blocked by the control arm (red arrow)

All the videos I've seen, their brackets are smaller and they can push it lower and that bolt can come off.

 

I believe I loosened all bolts that hold the pump then pull it forward which will allow it to rotate pass the arm giving access to the tensioner bolt

 

Yes. The pump has to slide up (pivot) to get that bolt out. I put the bolt back in the pump. Use a screwdriver and a rubber mallet at pivot the pump up.
You will need to do this again to get the 2 bolts back in after the belt is replaced. I just found this the easiest way myself.

 

Did I mess up?

Before I removed t belt, I set crankshaft 60 degree BTDC (about 10' clock position) but I turned it clock wise. I just read the instruction that came with the aisin kit, it says to do it counter clockwise. I guess no harm done right, as long as it is 60 BTDC ?

Also, when I removed the belt, both rear cam and front cam jumped, which was a little concerning at first. Rear cam timing mark is at 5' clock and front is about 4' Clock. I can just turn them (clockwise)with a ratchet and reset the timing marks before belt installation, right ?

Does the cams move independently of the crankshaft ?

 

The valve springs have enough force to push the cam to a "happy" position. So, it isn't uncommon for the cam to move slightly when the belt is removed.
Keep in mind that the crankshaft rotates twice for every rotation of the camshaft. The new belt could be installed correctly to the marks, but 180 degrees out of phase.
So, be careful and think about what you are doing. You don't want to start randomly rotating camshafts.

Hopefully you marked the old and new camshafts with paint marker. this will make it much easier to get everything correct when the valve springs are trying to rotate the cams out of position.

 

I think you're going way overboard. Assuming you lined the crank and cams up before taking the belt off and just moved the crank off TDC per the FSM, all you have to do is move the crank back to TDC and make sure the cam dots are on their marks. No need to remove the valve covers. That's an awful lot of extra work.

 

I agree with Roader. But if it gives you peace of mind what can I say. When I did mine and released the belt tensioner the firewall side cam sprocket rotated on me (facing the sprockets) , it rotated clockwise , scared me too! The crankshaft marks were still closely in alignment and the right cam sprocket pretty much stayed put. I may be wrong but I believe there is no way the crank nor both sprockets could have rotated one revolution. And as Roader suggest moving the crank and cam dots back into their respected position should suffice. If you decide to remove the valve covers you may as well renew the valve cover gaskets. Again if it makes you feel better , go ahead with your plan.
Paul

 

If you decide to remove the valve covers you may as well renew the valve cover gaskets. Again if it makes you feel better , go ahead with your plan.
Paul

yeah, so my plan from the get-go was to renew the rear valve cover gasket anyway. I already did the front one a few weeks ago. Maybe I wont remove the front cover and just put something in the spark plug wells and measure how far down are the pistons as I rotate the crank.

 

Just remember that, without a belt, the cams aren't going to be in synch with the crank. You could have pistons running into open valves if you turn the crank on its own.

I personally experienced this on a Lexus rx330 that uses this same engine, I was trying to fix a timing belt gone wrong by a new technician, what I found is that if the crankshaft is at top dead center that the rear camshaft can only turn about 90 degrees before the valves contact the pistons and neither cam or crank can be moved any further.

https://www.justanswer.com/toyota/3sugy-sienna-toyota-documentation-says-non.html