1JZ/2JZ owners, ever seen this?

[Norbie]

After pulling the harmonic balancer off my 2JZ I found this:





Obviously the balancer has been touching the plastic cover and over the ~5 years since I last had it off it's ground all the way through it. What confuses me is how this came about; the cover was securely bolted down and the balancer hadn't been wobbling (I know this because the crank and keyway aren't shagged). So WTF happened? Any ideas?

Also if anyone has a spare cover they'd like to sell please contact me. Does anyone know if the 1JZ cover is compatible? I suspect not but it's worth asking.

[silver_ta22]

i just did the timing belt a week or two ago on my 1jz, my cover had some rubbing marks on it, but nothing close to that, just a round groove from balancer. i can see how it would be possible if something was a little loose.

1jz cover looks the same based on pics, worth checking.

[Norbie]

Hmmm interesting. In the first pic you can see bubbles in the plastic, I wonder if the whole thing was starting to swell/warp and this made it touch the balancer? Note the front main seal has been leaking for a while so it's been covered in oil for ages.

[Negative Boost]

Thats what i was thinking when i saw the bubbles in the plastic. If it was due to the leaky seal that area would get hit first and swell big time.

[gianttomato]

The bubbles in the plastic are located only in the are directly under the crank pulley/harmonic balancer. I would suggest that the bubbles are more like "galling" due to the balancer rubbing against the plastic intermittently.

Just wondering if the bolts holding that bit of the timing belt cover were lose or the timing cover was not accurately positioned when the bolts were done up.

[Norbie]

Pretty sure the bolts were tight when I took it off. I don't think it's possible to misalign it with all the bolts in?

[thechuckster]

how much junk/gunk was on the back of the balancer?

oil+ dirt wiped at high speed is quite abbrasive and the heat from all of that would only add to the problem.

[Norbie]

There wasn't much gunk on/behind the balancer but a fair bit around it.

I guess if something hard and abrasive got back there it would do some damage, but it would have to occur over an extended period for this to happen, and surely any foreign objects would get spat out fairly quickly? It's the most likely explanation so far though.

[BMWTurbo]

I've pulled 1jz ones off with scuff and wear marks, but all my 2jz ones have been okay.. Maybe the engine had a balancer replacement at an earlier date?

[IN 05 NT]

do the 1js have a washer that sits between the timing gear and the harmonic balancer?

ie that may be one reason wht its rubbing so bad if it hasnt been replaced last time round??

blake

[Norbie]

Maybe the engine had a balancer replacement at an earlier date?

I replaced the timing belt ~5 years ago (didn't replace balancer) and there was no damage then, so something has happened since then!

[dori dori]

The rubber damper in the balancer is still ok?

[ReQuieM]

Mine was fine when I did it but a mates had scuff marks, not that bad tho. and My spare 1J has some light stuff.

Was it tightened to the correct torque? within reason of course!

Also you had that 'washer' that was mentioned earlier on the timing belt cog between the plastic and it? perhaps the 'washer' was missaligned and holding the plastic cover out further then it should of?

[Norbie]

The only thing between the timing cog and the balancer is the thin steel belt retainer thingy. Is there supposed to be anything else there?

[ReQuieM]

Nah thats the one I'm thinking of I'm pretty sure.

BTW I reckon you might be able to get away with a 1JZ cover, I know the block is taller but that bottom section looks very similar.