Question on Correcting Timing

Hi all,

First an introduction. I picked up my 1st gen a couple weekends ago and just signed up for an account here. (huge admiration of the knowledge and community here! But that's besides the point)

Last weekend I undertook the timing belt and water pump job. I did a fair amount of research and purchased the Aisin kit with water pump and tensioner.

I did notice that the crank timing seemed a bit ahead of where it should have been but in all honesty, it was my first time doing a timing job and I wanted to keep all synchronization with the new belt identical to the old belt since I knew the truck was running and I was a bit intimidated with changing the timing characteristics. But with hindsight and all...

No real problems with the replacement, the truck's been buttoned up and driven roughly 75 miles with no issue.

That aside, I'll be opening the truck up again this weekend to address what seems to be a slow leak from the new water pump. The truck did fine for a couple days but I noticed a couple small puddles of coolant underneath it this past Wednesday. I checked the timing belt and noticed it was slightly wet and parked it immediately. I searched around the forum and believe I've checked all the hoses recommended to others who had been in a similar situation. I'm thinking I did not torque the water pump down quite enough, picked up a beefier torque wrench (mistakenly got an in/lb last time) to accomplish it this time.

My main question here is in regards to that crank misalignment. I didn't get a photo of it previously, so I'll reference this one I lifted from the kind hearts at ToyotaHQ.

I understand that the small post sticking out from the plastic cover (yellow arrows) is where the timing mark in the crank should be when the cams are aligned to the "T" marks up top.

In the condition I got my truck, the crank aligns to the center of the bolt hole (red "circle") when the cams are aligned at the T's



I also think the truck has been running a bit rich due to a strong smell of unburnt fuel in the exhaust, I believe bad timing may be the culprit.

I plan to correct the position of the crank when I am back inside the covers this weekend.

Do you guys have any advice on going about this? It seems fairly straight forward but I am no savant and would like to keep this truck on the road as long as I can.


Thanks in advance!

 

Check out this post from another site. It may answer a lot of yor questions.
Toyota 2UZ-FE Timing Belt Marks 4.7L | TOYO Headquarters

 

This is the de-facto best single source for timing info on the internet, at least for our V8.

 

Learned about it from you!

 

Copy that,

Thanks for the replies gents!

I'll update how it goes over the weekend

 

Did you scrape all the residual gasket material off the block before installing the new gasket/ WP? A little bit of leaking from the water pump weep hole is normal, but it shouldn't last and it shouldn't be enough to puddle much. If you re-used your hoses and hose clamps, you'll need to set the clamps in the same exact place they were before otherwise they may not clamp properly and can leak there. The clamps can also lose their "spring" over time.

 

Rich smell is generally present at startup in open loop fuel trim until O2 sensors warm up. If it persists, then O2 sensors are a possible culprit.

 

Hi all,

@des2mtn, Thank you for the response . I scraped the old gasket material off as much as I practically could without a wire brush or carbide scraper. It was clean when I attached the gasket. I am however in a very dusty part of the country and had to initially do the timing job outside in the wind. Hoping that did not affect it too much, and I've since moved the truck inside to retighten the pump. I believe I made a mistake of installing the studs late and did not get them tight enough. They were quite loose...But I will be checking all water pump bolts with the torque wrench.

@KNABORES Thank you for the response as well! I will compare the small upon cold start to that when it is warmed up. Thanks for the tip!


Timing Progress update,

I've gotten just about everything back apart and have some new photos. I've read through the post on toyotaHQ and will definitely be referencing it to realign the marks. Thanks!

Here is the truck in it's current state of timing



This was an oil field truck and has likely had a rougher life. I'm guessing the crank skipped a tooth or two somewhere along the way. I'll be addressing this today while I'm here.

I would just like some reassurance on my thought process.

How I see it going:

1. Set the timing on crank and cams to ATDC (done)
2. Remove crank bolt/pully/plastic cover
3. Remove belt tensioner (I will have to reuse the new one that came with the Aisin kit. I'll press the tensioner down slowly and insert a thin allen key to act as the Pin)
4. Remove belt
5. Reinstall crank pulley/cover/and crank bolt
6. Adjust crank timing to align with the plastic post in the crank cover
7. Disassemble once more to reinstall belt and tensioner
8. Attach crank bolt and give it test rotations (in cycles of 2 crank rotations) to make sure everything lines up


Time for a beer break

Thanks in advance fellas

Cheers!

 

Next Update:

I have tightened the water pump bolts.

I'm ashamed to admit how loose a couple of those were... But they are torqued to spec now

Removed the timing belt and attempted to retorque the idler pulleys as well, but the torque wrench I rented seems to be damaged and will not go lower than 55ftlb, although it's rated for 25-250ftlbs. Due to this, I've retorqued them to as much as I was comfortable doing blind, and applied a small bit of blue loctite to their bolt threads for peace of mind.


I found a the write up @Weagle made in the master timing thread (much appreciated sir) and followed his advice to not recompress the new belt tensioner.


I followed the steps I outlined in the above post and rotated the crank (independent from cams) back into place using the marks on the crank pulley and cover




Now the crank pulley (and therefore the crank) is aligned in the correct position according to the marking images over at the ToyotaHQ timing thread.

I will be reinstalling the belt and tensioner, making sure not to rotate anything, and giving the motor a few manual turns to see that we are all good.

I don't expect I'll have it all buttoned up today, but I'll update on progress.



Cheers!

 

You should really consider replacing those crusty ass PCV hoses.

 

Trust me they're worse in person, I was afraid to touch them! I'll take care of them soon.




Post Manual Rotation Update:

The crank and cams are now aligned (after cycles of two crank rotations) at TDC and ATDC

I want to make clear that I've had no engine trouble or misfires the entire time I've been driving this truck, quite the opposite. I'm very surprised at this given that the crank had been out of sync with the rest of the system this whole time!



Here are the final results of the timing adjustment


TDC Marks




ATDC Marks






May be a degree or two off, but that looks pretty damn close to me, and much better than it was initially.


I'll be finishing up the job tomorrow, I pray that the water pump leak is resolved. But hey if not, at least I know my way around the front of the engine now! I'll get a new gasket in there if need be.


Thank the lord for all the help and info this forum has provided. This thing is gold!




Have a nice night fellas

 

Where the hell are the stripes on that belt? What brand is it, that it doesn't have timing alignment marks on the belt?

 

I think the lines on the belt only line up with the marks every few hundred rotations or something like that as the cam and crank pulleys have a smaller diameter, so the belt hasn't done a full revolution each time the pulleys have. Or something like that. I could be smoking something.....

 

Aisin belt, made sure to get the right kit.

It had the CR/ L-Cam/ R-Cam Poka-Yok originally, but I had been driving this thing a bit so they must have rubbed off. The drip from the water pump onto the belt couldn't have helped either!

Made it a bit trickier to not skip any teeth, but it did still have the dots on the side for the crank so I lined those up and pulled as much tension as I reasonably could up to the drivers side crank.

Correct me if I'm wrong, but as long as the three marks are all still aligned after rotation the motor should be good right?

 

I was under the impression the marks on the belt were for install only and won't always line up every time after the engine's been ran and the belt has tension, even if the sprockets are still lined up. Could be wrong though.

 

You know there is a simple way to move the cams one tooth at a time using a screwdriver hex bit under the belt?

 

They aren't always 100% spot on, just in the ballpark ... as mentioned above it's part of Toyota's Poka-Yoke system ("fail proofing/dummy proofing), it's pretty cool. More of a sanity check than anything.

I just found it strange there's no marks, some folks still have marks on their belts after 80k+ miles on them. I realize they're not required to get the job done, I was more interested in the brand/source of the belt, that the marks weren't there.