SATXSC400

Posting this here also because I know you 2nd gen GS guys have changed out your VVTi cam gears before. Ok guys I'm in the process of changing out the timing belt, cam seals, tensioner, tensioner pulley, waterpump, and a new VVti cam gear on a 98 SC300. Well everything was going good until it came time to change the VVti cam gear. The 10mm hex bolt was really torqued down, I would say over 300 ftlb. I had to use a large impact gun to bust that hex bolt loose. I had a buddy hold the cam with a wrench on top while I hit it with the gun. Well I finally got everything changed out and put on the new timing belt that I had marked exactly like the old belt prior to removing it. I made sure the VVTi cam gear was within the 30 degree range and stopped at the timing mark on top. Well with the timing belt on and the tensioner pin pulled out I rotated the crank to make sure it stayed on time. Well the belt jumped a tooth on both cam sprockets and the crank sprocket as well. I did a few full rotations and it seems like the belt is advancing a tooth with each full rotation. So I went ahead and put the bottom timing cover back on and realigned the timing belt following the FSM exactly and rotated the crank and its still advancing a tooth. I must say I'm confused, this isn't my first timing belt change. I just did a belt on a 2002 Lexus Is300 last week, everything went smooth as butter. The only thing different was I didn't have to replace the VVti cam pulley on the IS300. I verified that I have the correct timing belt and cam sprocket. I've done dozens of timing belt changes before, everything from 2js, 7ms, to Honda B and D series motors. I'm stumped for the night , gonna start fresh tomorrow. Any input from you seasoned Lexus guys would be great. Thanks..!!

99SC42

iTrader: (44)

here you go man i am thinking about doing the same thing tomorrow but you scaring the Hell out of me
here is a link it may help you GL

https://www.clublexus.com/forums/gs-...ing-a-2jz.html

JeffTsai

iTrader: (1)

So what can't you get right? Once you put the VVTi pulley back on, advance it all the way to the right(clockwise) till it stops turning. At this position is what you use to line up the timing marks on the pulley with the notch on the back metal cover. So, dot on intake pulley match to exhaust side dot on the pulley, or line to line. Match it up to crankshaft accordingly.

99SC42

iTrader: (44)

jEFF i think he just put the hex bolt back on the VVTi cam sprocket and didn't turn it till it stop turning that was the problem

SATXSC400

^ Thanks for the help so far guys, I really appreciate it. But I did actually did put the 10mm Hex bolt back on and made sure the VVTi cam gear rotates the 30 degrees and stops right at 12 O'clock aligned with the mark on the metal back plate. I put everything back on with the cam gears aligned with the back plate and tensioner pin pulled out. I then rotate the assembly to make sure the belt doesn't jump timing, its a habit of mine. I've always done that step to make sure it the belt doesn't jump. But on this motor with each full rotation of the crank I notice the belt advances a tooth each time. I know it does because I marked the new T-belt. Is this normal for a VVTi motor? I just did a 2002 Is300 last week and I don't recall it doing that. I definitely know Honda motors don't do that.

SATXSC400

Well got everything back together yesterday and it started right up. No problems at all. I guess its normal for the TB to advance on the cam gears, I figured it was ok since the TB advanced on all three gears not just one. Thanks for all the help guys, the next VVTi cam gear/TB change will be a breeze.

99SC42

iTrader: (44)

Well i try to replace mine yesterday i was half way there when the Crank pulley bolt wouldn't come lose i broke 3 of my breaker bar finally i just put everything back and went home ,i am going to mess with it next week. Congrat man

JeffTsai

iTrader: (1)

Yep the belt moves fowads one tooth every rotation or so. It's normal. I think its because the cam gears have odd number or teeth and the crank has even. Something like that. I never bothered to count but that's just my theory lol.

Also, keep in mind. Most modern cars with more sophisticated ECU's can compensate for timing being off by 1 or 2 teeth. Of course it's always best to line it up exactly, but I'm just letting you know the ecu has a very slight tolerance for error.

SATXSC400

I found it much easier to remove the front bumper and use one of those 1" 1600 Ftlb diesel impact guns to bust loose the crank bolt.

blueis6

Hey, I know this is an old post but I'm stuck on my timing or whatever it is. I removed the VVTI and turned it too much. I need to get it back right. So turning it a full 360 don't matter as long as it's on the marks? What is this 30 degree thing and stopping on the timing marks? Can you elaborate on how to do this? Can't find no info online. So mine from the timing point 60 degree btdc or the circle on the cam can rotate about 30 degrees clockwise until it stops. Is that right? Or is it supposed to be able to move counter clockwise from the 60 degree btdc till it stops? Thanks in advance.

Sinnerav

So my brother did the timing on my 2000 gs 30 3.0
L 2jz ge vvti.
after he was done started fine ran fine. the next day the car is running like **** there are 8 different obd codes now. come to find out he set the timing with the lines on the top and he said the crank shift turned a lil once or twice trying to get to the crank shaft seal. also the vcs and vcs off light is also on now. i am running with no rear cat so the engine light is always on. But when I started it the engine light started to blink. i shut it off and havent touched it since that was 5 days ago. some one please tell me how to fix it. I can do it myself, i just didnt know exactly how. I watch him take it apart so I can take it apart fix it and put it back together now. I just dont know how to readjust/reset the timing. some one please help. thank you
paul.

CRASHMONK

iTrader: (1)

Sounds like you need to reset timing. There's a few ways to go about that. You can tear it all the way back down, set crank to TDC, and line your cams up.

OR

If you're VERY CAREFUL, you can:
(Without tearing everything apart)

set crank to tdc: which ever makes the cams line up close to their marks MAKE SURE YOU DON'T BUMP IT OUT OF TDC

loosen up your belt tensioner (may have to remove completely for enough slack but shouldn't be necessary)

Assuming the crank got rotated clockwise a tooth too far, you can assume the cams need to go clockwise 2 teeth each due to the 2:1 ratio.
with a wrench or ratchet, rotate the cam sprockets forward and make the belt jump until they're in position and lined up.

tighten up belt tensioner

Make absolutely sure you have the marks spot on before actually running the engine.

Even after you're sure, rotate the engine AT LEAST 2 full revolutions BY HAND SLOWLY so as not to bend valves accidentally. If you feel the engine stop, don't push any further. Check timing again after rotating, I've screwed up timing marks even when i thought i had them right.

If you're 100% satisfied with your timing marks, DOUBLE CHECK your work and check all bolts are tight. Be careful tightening bolts in aluminum threads.

Reassemble and drink beer to celebrate.

You'll want to find a diagram or pictures that show where timing marks are.

Sinnerav

i did get the whole thing apart. got the crankshaft at TDC took the belt off to set the cams I got the right side cam set. the exhaust side cam wont rotate completly and It wont go either way enought to set the timing mark at TDC. Does this mean the damaage has already bern done? It rotates with the timing belt on and when I turn the motor by the crank shaft but it wont turn freely like the rightside cam does. it only turns about a quarter of the way in either direction. what am I up against now. Caus I have a bad feeling the response to this isnt gonna be a pretty one. I. Wanna thank those of you that are helping me with this. I truly appreciate so much.
paul

CRASHMONK

iTrader: (1)

Just to be totally sure, could you post pics of where you have your marks set up?

Sinnerav

got both og the cams lined up but the crankshaft is one tooth off to the left.