[MarcsSportcross]

I'm doing my timing belt today. It had been replaced once prior to me owning it. I have the crank at TDC/0, but the cam gears are off (I haven't removed the belt yet). The "dots" are lined up with the notches in the cover, but the hash marks on the gears are still at about 11 O'Clock. In other words, it seems whoever did the replacement last put the belt back on with the dots lined up instead of the hash marks. I guess that means they retarded the valve timing. I have had the car for a couple years and it runs fine.

First, am I correct thatthey were wrong to line up the "dots"? Secondly, I plan to put it back together with the hash marks lined up with the notches in the gear cover. Does anybody see a problem with this?

Thanks

 

[MarcsSportcross]

Mods - please delete this thread because I am an idiot. I didn't realize there was a second timing mark on the harmonic balancer. All is good.

 

[ill_mannered]

Mods - please delete this thread because I am an idiot. I didn't realize there was a second timing mark on the harmonic balancer. All is good.

I was going to tell you to rotate the crank just a little more and you would have seen the other crank timing mark.

 

[MarcsSportcross]

I was going to tell you to rotate the crank just a little more and you would have seen the other crank timing mark.

Yeah, I'm a dummy. The first mark had paint on it too so I just assumed that was it. I didn't finish today as I had quite a bit of cleaning and replaced the cam/crank seals. I bought an O-ring for the VVti gear, but it doesn't seem to be leaking so I don't think I am going to break it open. I'm still on the fence on that. I'm worried that it will start leaking shortly after I do the timing belt, but I am also worried I will screw up the O-ring and induce a leak.

I guess that will be a decision for tomorrow.

 

[ill_mannered]

Yeah, I'm a dummy. The first mark had paint on it too so I just assumed that was it. I didn't finish today as I had quite a bit of cleaning and replaced the cam/crank seals. I bought an O-ring for the VVti gear, but it doesn't seem to be leaking so I don't think I am going to break it open. I'm still on the fence on that. I'm worried that it will start leaking shortly after I do the timing belt, but I am also worried I will screw up the O-ring and induce a leak.

I guess that will be a decision for tomorrow.

Just did 3 2JZ timing belt and water pump jobs within 3-4 months ago. One had 235k miles. Leaking oil ALL OVER the front of the motor. Changed the cam seals, crank seal, and valve cover gaskets. Did not touch the o-ring as it wasn’t leaking. Still holding up just fine. Second car was my wife’s (162k miles) also fair amount of oil but nothing like the first one. Didn’t replace o-ring either. Last one....you guessed it. Didn’t touch the o-ring either.

That being said, it is entirely up to you. Change it if you would like. They really aren’t that bad to pull apart. Just make sure you place it back together the same way.

 

[Kris OK]

really aren’t that bad to pull apart. Just make sure you place it back together the same way.

Yeah, I did my VVTi gear on my GE and GTE. Not bad at all. Getting the o-ring to stay when reassembling is kind of a pain. If you decide to do it, take a carbide scribe and make some witness marks on it, that way you can reassemble it exactly how it was from Toyota.

 

[MarcsSportcross]

I ended up just leaving it as is. The replacement seems pretty straightforward, but I was concerned about how the o-ring shrinks. You stretch it, put it in the groove and put the other piece on top. But I kept thinking it would shrink and come out of the groove before I got the bolts in and wouldn't see it because the other piece is on top of it. I'm fairly sure the weight on the other piece is enough to keep the o-ring in the groove, but couldn't get past that fear.

On the plus side, the job is done and the engine didn't grenade. There don't appear to be any leaks anywhere either.

 

[Pnut00]

I ended up just leaving it as is. The replacement seems pretty straightforward, but I was concerned about how the o-ring shrinks. You stretch it, put it in the groove and put the other piece on top. But I kept thinking it would shrink and come out of the groove before I got the bolts in and wouldn't see it because the other piece is on top of it. I'm fairly sure the weight on the other piece is enough to keep the o-ring in the groove, but couldn't get past that fear.

On the plus side, the job is done and the engine didn't grenade. There don't appear to be any leaks anywhere either.

I never did the VVTI gear either, they dont seem to be that big of an issue from what i have read unless its getting high miles.

Nice feeling at the other end when all the work is done, start it up and its all purring again!

 

[Allgonquin]

I did the VVT gear O ring as a stand alone job. Getting it to seat in the groove was a huge PITA. Good thing I bought 2 O rings. (bought off Ebay, supposedly good material, good quality, etc. - supposedly a CAT diesel part IIRC and much cheaper than Lexus OEM) I ended up using superglue to secure the O ring in the groove, after I destroyed the first O ring, thinking it was in the groove, buttoning back up, starting the engine and having a mess. I just used superglue in a few spots in the groove, not all the way around. My logic was that as long as it held for the short time to secure the gear back together, it did not matter, and in fact it would be better, if the glue gave up once the car was running. So far no issues many thousands of miles down the road. I only wonder if the OEM O ring might have been easier to seat in the groove without extraordinary measures like superglue.

 

[Pnut00]

As I've not pulled one apart I'm not 100% on the construction, but in general while you can use superglue to hold o-rings in place its not ideal. I have used it before as well when there is no other choice on a static seal, but you need to be aware of the risks. The problem with superglue is that it forms a hard shell which will chip off the flexing o-ring over time if it is a dynamic seal, potentially it could be big enough to block off an oil way or a filter, or worse small enough to get between some sliding surfaces. Also the glue is rigid and teds to bind to the rubber which is supposed to be flexing, possibly causing the o-ring to deteriorate prematurely or perhaps not allow it to seal effectively, especially if the o-ring needs to move but is being held in shape or in place. Better to use a thick sticky grease to hold the o-ring in place that can wash out if needed and dissipate into the oil.

 

[MarcsSportcross]

I did the VVT gear O ring as a stand alone job. Getting it to seat in the groove was a huge PITA. Good thing I bought 2 O rings. (bought off Ebay, supposedly good material, good quality, etc. - supposedly a CAT diesel part IIRC and much cheaper than Lexus OEM) I ended up using superglue to secure the O ring in the groove, after I destroyed the first O ring, thinking it was in the groove, buttoning back up, starting the engine and having a mess. I just used superglue in a few spots in the groove, not all the way around. My logic was that as long as it held for the short time to secure the gear back together, it did not matter, and in fact it would be better, if the glue gave up once the car was running. So far no issues many thousands of miles down the road. I only wonder if the OEM O ring might have been easier to seat in the groove without extraordinary measures like superglue.

Yep, that was my exact fear.