jnaka16

Hi, I'm new and was planning on doing a tbelt job on my gs300 and was reading up on it. The one thing I am lost on is reinstalling the VVTI intake cam sprocket. I know it says to install and line up the dot but I was also reading that the sprocket can turn up to 30 degrees. When I reinstall it, do I turn the sprocket all the way clockwise or counterclockwise then line up the dots? Any help is greatly appreciated. BTW, I downloaded the factory manual and it doesn't say anything about it in there. Thanks in advance

jnaka16

also, will the radio lock up if I disconnect the battery to do this job, and is there any other issues I may have to deal with when I disconnect the battery?

maximus54

iTrader: (4)

You turn it all the way to the right/clock wise. Yes your radio will be reset, you will lose all settings and presets.

WaltL

I just completed a T-belt/H2O pump service today. I'm also new to Lexus and the 2JZ motor. I posted yesterday on this topic but no one chimed in with an answer so I did not remove the sprocket. Unless your camshaft seals are leaking (mine were not) I see no reason to remove the sprockets. The manual says do it, but doesn't indicate why it's necessary.

Here's a few things I learned:
1) No need to remove the radiator, just remove the fan assembly (6 bolts and three elec. connectors.

2) Go ahead and take off the alternator (2 bolts) and set it off to the side (you don't need to take off elec. connections). Also take off and set to the side the PS pump (4 bolts and 1 elec. connector). This allows access to the tensioner bolts and lower T-cover bolts that are a PITA to get to otherwise.

3) If you don't have the Schley tool for holding the crankshaft pulley while you break the bolt, buy it or borrow it. I used two 5 ft. pieces of 1" pipe over two my 1/2" drive breaker bars plus the help of a friend to get that sucker off... insanely tight!

4) The water pump O-ring (the one that fits into a recess in the block and mates to the back of the pump) appeared to be too large and did not fit at first. I had to mess with it for ~ 30 min. before I finally got it to stay in place without falling out so I could mount the pump.

Timing belt installation:
Jeff's YouTube series are helpful to watch if you haven't done so
http://www.youtube.com/watch?v=-fiHrC7xT5o

I simply aligned the crankshaft as described with the first timing mark, it's yellow, at 0 degrees and the camshaft pulley marks were aligned with the rear timing cover marks. You may have to rotate the crank through two full revolutions to get everything to line up right.

Before I removed it, I counted the # of teeth on the old T-belt between the two camshaft timing marks (there are 16) and I made locating marks on the new belt (factory belts may have these, but my Gates belt did not). When I installed the new belt, I aligned it so the right most locating mark would be in its correct position on the VVTi camshaft. Starting on the right side and going around the crankshaft gear I took out as much slack as I could with the belt locating mark falling in place at the VVTi pulley mark. The belt is then positioned so the second mark is in it's place on the exhaust cam pulley and all the slack should be on the left side between the exh. pulley and the crank. Engaging the tensioner then takes up the slack.

After the crankshaft pulley is reinstalled, but before it's torqued down, rotate the crank pulley through two full revolutions to get the yellow crank timing mark back in position and confirm that the camshaft pulley marks are also still aligned correctly. Then torque the crank pulley and reassemble everything else.

Anyway, that's how I did it. I buttoned her up and she runs like a top. I did a 20 mile shakedown with no problems/issues found. It's nice knowing I just saved myself ~ $500-$600 and I'm looking forward to another 100K miles before I have to go in there again

Tomorrow I'm doing new plugs and fluid flushes/changes.

jnaka16

Thanks guys, I'm sure it will go with no problems.

Walt, I need to remove the sprocket because it is leaking from the seal.
Does the radio just reset when I disconnect the battery, or does it lock up to where I would need a code from the dealer?

maximus54

iTrader: (4)

i believe it just resets. never heard of any issues with that.

WaltL

The radio did not require a code and, interestingly, it also kept my presets stored.

jnaka16

Alright thanks again for the replies. I was just worried because my fiance's 06 Accord will lock you out of the radio until you input a code.

13Checkers

A late addition to this thread, in case anyone brings it up in a search (as I did.)
There are a couple of very good reasons to replace the cam seals while doing a timing belt.

In the first place, they are wear parts: parts that are designed to eventually wear out. As designed, they should not wear out in one timing belt life cycle... but they will most likely wear out before the second timing belt wears out. Replacing them when the belt is replaced (as is intended.. and when you are practically looking right at them) will save you from having to go back in and remove everything again to get to them.

Secondly, oil is bad for timing belts. Leaking oil can ruin a timing belt. Your engine is an interference engine. (In other words, if a valve remains open when the piston comes to TDC, the piston will contact the valve.) If a timing belt fails (due to oil contamination, or any other reason) when the engine is running, the very least damage that can be expected is bent valves. Possible damage could be a lot worse.

This should be easily enough reason to replace the cam seals as specified.

tangotim

I wish that I would of read the post about replacement of cam seals when doing the timing belt.
I did not and now am worrying about oil ruining my new belt. To late now, I hope that the seals will last to 210,100 miles.

RPrescott

When I changed my timing belt a couple months ago I was really worried about camshaft position when reinstalling the Intake cam sprocket. Couldn't find anything anywhere. When I stopped worrying and actually thought about how the system works, I realized why I couldn't find anything - it doesn't matter. Get the timing marks on the sprockets aligned to the bumps in the shroud (like the book says), and press on. The VVTi system changes the relative orientation of the cam to the sprocket, so the cam is essentially "floating" in that 30 degree window. The orientation of the sprockets is what matters.

wbmx1981

I'm gettting ready for a TB job. I'm trying not to remove the valver covers because I just replaced the valve cover gaskets in early August. I know the service manual calls for removing the covers to hold the cam shaft while removing both the intake and exhaust cam gears. I've read that people have used a piece of rubber and a chain wrench works in holding the gear too. What are some things other people are doing in these cases or is just removing the valver cover the best and safest way to go. If I do remove the valve covers do I need to also replace the valve cover gasket since gaskets are not reusable (the gaskets are not even a month old)?

wbmx1981

Okay that's what I thought. Thanks for the response.

wbmx1981

I found these pics online. They seem to be very helpful, for someone doing the TBelt job, seals job.

https://picasaweb.google.com/ineedmo...at=directlink#

repugnante

If you are worried about the positioning of the cams when doing a timing belt replacement, all you have to do is set the timing to TDC. Zero degrees at the crank, hash marks on the cam sprockets.