Some where in the exchange of notes, I am lost.

is the "|" mark right or "T" is correct. If "T" is correct then perdesi you were off by 2 teeth ... based on the last photos. May be you fixed that when you compared with your brother's car.

Salim

 

I think you are chasing the wrong tail. If the timing is off a couple of tooth, the car would start. Valves will start touching the pistons around 1/4 of the turn on cam sprocket. I've seen a couple times people jump the battery backward and it would ruin the ECU. In this case, I would think it's an electrical problem not mechanical. Make sure you do have 12V going to the ECU. Pin BM + and Batt, also once you turn the vehicle. PIN IGSW should get 12v. Get all EWD out and star tracing the problem.
JP Importz

 

What i found out was that if you use the T marks then your crankshaft pulley is no longer set at the 0 mark, instead in the image i attached above notice how its marked with the second pully (50 degree clockwise). Then if you do your two rotation it will match up with the "l" mark and also the 0 on the crankshaft pully mark.

 

Well no good news except they did get the car started and only running on 4 cylinders... i guess u can bend the valves if the car does not start and only cranks.... so no compression in the L side. The one I screwed up on the very first time.

Live and Learn… So its winter here and car is back in my garage and I have my truck out for the winter.

So should I even ask … Doable or NOT… I would take it in to a machine shop to get the valves installed and get all the valve setting done by them.

I have another option… find a L head somewhere and have it checkout by a machine shop then just install it. (Anyone have one laying around)

 

PARDESI,
I am SO SO SORRY that this happened to you. I have never taken the heads off of the IUZFE, but it is pretty straightforward.

It appears the valves bent upon startup, and was never right after that. The backfire was the giveaway in my mind. IT IS confusing having two sets of marks and all, but I say that experience is the best teacher, and you'll never make THAT mistake again.

This is a terrible time to have your car down....(actually ANY time is a bad time, but NOW is an especially bad time.)

I wished there was something I couold do or say to make it better but I can't.

Stay encouraged and if you thnk you can take it down yourself I would say go for it. Mark everything, and remember to separate all the cams and followers. They all go in exactly the same place upon reassembly.

The machine shop of your choice can replace the bent valves, and lap them into place. Your 4 cams should be fine, but have them checked anyway. This is a very complex engine with a lot of moving parts. I wouldn't try to do this job without a factory manual. There is a definite sequence to tightening the head bolts down in steps...such as half the torque first, then around again with another 25%, and then the final 25% the last time around. The head bolts may have to be replaced as they often stretch once they are torqued down.

I'd say to get a quote at the dealership to do the whole thing. Then check your wallet and make a decision.

Please keep in touch and let us know how it all came out.

GOOD LUCK

 

Hey thank!... yeah no biggy things happen. I've got the full instruction on how to do it, step by step and should have the torque specifications as well in it. I've done head replacement in the past on few other cars. Nothing this complicated but shouldn't be too bad. Like you said mark everything and i do have the factory manual online. Plus i'll have you guys here to ask for help And the actual valve replacement, that i won't tackle and will send it to the machine shop.

The way i look at it i've done starter on the GS400 and that requires removal of the intake, the front is easy to take out to get to the timing belt. I've removed the cam head few times. So what is left is the three bolts which connects to the cadilac converter and then removal of the cams and then rest of the bolts on the cylinder heads. So lets see, i'm also looking around town for shops and etc.

I do have few other questions if taking it to the machine shop to put the new valves in is the correct way to go OR buy a used head with cams and valves already in it assuming they have done all the checks. Lets see I found a L head already but the cost of me getting it here and having the machine shop inspect/resurface it is the same cost for me to just take mine out and giving it to them to redo the valves and adjust them. Any thoughts! Will the new valves be of same quality as the original ones in the car?

I'll keep you guys updated. Thanks again to everyone here on the CL forum for all the help/suggestion/feedback.

Pardesi

 

Pulling the head off isn't too bad. But setting up the cam timing is very very crucial.
1. I've seen many lexus tech make same mistake and bent the exhuast valve on cylinder #3. If you followed the instruction from manual, it would instruct you to move away 50degree. Using this method, the #1 cylinder is safe but not #3. Cylinder #3 exhuast valves are now push down.
2. When removing the cams, Make sure you put a 10mm bolt on the scissor sprocet. Don't forget to line up with dots. One dot to one dot. Two dot to two dot. Remove the bolt when you reinstalling the cam(I've seen many lexust tech to do so).
3. Replace your cam seals why are you at it. Again, Do not remove the VVT-i controller!!!!!! Otherwsise the timing will out of sync.
4. Mark all your valve buckets. Don't mix them up. Lexus uses the shims under valve buckets. These shims are very small. Make sure they are in place when you reassemble the head.
5. You will need to invest a tool to reassemble the head valve springs. They can be obtain for $50 from the tool truck.
6. Have your heads and valves inspect by the machine shop. I would request them go over the valve seats throughout. I would order the valves from Lexus not some aftmarket company. They are $12 each.
7. Inspect your pistons. Check for damaged on surfaces.
8. Torque your head in proper sequence. You would need to invest an angle measurement tool.
9. Torque the cam down in proper sequence(otherwise You will break it). These lexus cams ain't cheap. If you do break the cams and I hope don't break it. You would have to reshim the entire bank. The shims is about $10 each. So you do the math.
10. We've done plenty of these. And they aren't that easy like peope like it's.
11. I would look for an independent Lexus shop in your area to see how much would they charge for something like this. It's not cheap!! but you would rather let someone else have the experience to perform this kind of work.
12. Inspect to spend around $1500 on parts alone.
13. Good Luck!!!
JP Importz

 

I was comparing your comments to the instructions I have. (Below from the manual)
a. Check the crankshaft pulley position. Check that the timing mark of the crankshaft pulley is in aligned with the centers of the crankshaft pulley bolt and No.2 timing belt idler pulley bolt. NOTICE: Having the crankshaft pulley at the wrong angle can cause the piston head and valve head to come into contact with each other when you remove the camshaft, causing damage. So always set the crankshaft pulley at the correct angle.
3) Align the timing mark (2 dot marks) of the camshaft drive gear by turning the hexagon wrench head partion of the exhaust camshaft with a wrench.


The instructions I have didn’t mention anything about the 10mm bolt on the scissor sprocket. Were you referring to the service bolt? (see below image)

Thanks for letting me know, I’ll make sure to replace those seals as well. I looked up the VVT-I controller and nope I won’t be removing that. Thanks for the heads-up!

I plan on not touching the valves; will be taking the heads to Napa Machine shop to get them done. They quoted me the same price of $12 per valve (all 16 of them), I’ll check with them to see if they are getting them from Lexus.

I’m getting my hands on a nice torque wrench and per the instruction it shows the 22 cam bolts which need to be torque in particular order along with the spec.

Let me know if you are interested in the instructions I am using, I can PM them to you. Since you have done this before and can confirm the instructions if you have time.

And Thanks for Looking out!
Pardesi

 

PARDESI,
I am very interested in seeing how this procedure all comes out. You will definitely be the Lexus ENGINE MASTER after pulling this one off.

You have the right attitude about this so that will help as you go through this.

To the extent of my knowledge, I am here to help like so many others.

When will you get started on this?

At least you will have a totally rebuilt head if you do it yourself. I now realize just how complex the insides of the GS400/430 engine really is. I can ONLY IMAGINE how complex the new LS460 engine is.

I am going to do some research and see if that engine is gear driven or belt driven.

 

Oh i don't know about that but i certainly hope i can pull this off. So far i'm just going through the documentation on both removal and installation making sure i understand everything. I need to buy a few tools yet. But i do plan on getting started on it today.

Since i'm heading out of the country in another week or so. Hopefully before i go i'll have it removed and sent to the shop. When i return it should be done so end of this month i should have it up and running.

 

Important question (left head):

Is there any correlation between the two dot (timing mark) on the camshaft drive gears versus the L Camshaft timing pulley mark?

Reason i ask is because once the Camshaft timing plulley mark is set to the "l" mark, the cam gears are aligned with the one dot on the camshaft drive gear versus the two dots (timing marks).

 

Yes,
Those marks keep the intake and exhaust cams in proper relationship to each other on the same bank. These have to be lined up when assembling the cams after disassembly.

When doing a timing belt normally, this is never an issue as they are already timed to each other. But since you have to disassemble everything to get the head off, all this has to go back just like it came out. Pretty complex stuff in this area, but do-able if you take your time. I'd even photograph certain things if I thought I would forget something.

I would look at replacing the head bolts as they are known to stretch during normal use, and don't take too kindly to being retorqued after loosening. I HAVE heard of people reusing these, so I don't think it is REQUIRED to do so. Your choice.

With the head removed, clean the heck out of the mating surfaces and cover everything until you reassemble it with the new head. Just THINK, you are doing only 1 head.... It would have been budget breaking to have to do both heads. The labor is so intensive with all the moving parts.

You will also get to see just how good a job your motor oil is doing protecting the insides of your expensive engine. If THIS doesn't make you use good oil, nothing will.

Please keep us up to date on your progress. I have been wondering how you found a used left head in your searches. It is so critical down deep that I would STILL want to have the head checked before putting it on my engine...WOW, such a choice.

Thanks again... and HAPPY NEW YEAR!!!

 

Yup i agree, L head timing is set at the two dot marks, but if you look at the camshaft pulley at that time it's no longer set at the timing mark. I also confirmed that with my younger brothers GS400. But yeah i'll have plenty of pictures and labeling i will be doing.

No, i'm not going that route. It is costing me the same amount if i just take my head out and give it the machine shop to have the new valves put in along with other clean up of the head. Versus getting a used one shipped to me, then taking it in to have it inspected. So i rather just use the one i have at least i know the history of mine.

Thanks and happy new year, what a way to start a New Year

 

Well, i can clearly see the bent valves. Didn't get to taking the cams out today.

 

4 hours spent on Monday another 4 hours spent today and it's out...

Wrecked all 8 of the intake valves...