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Discussion Starter #1
So I went to just reseal and do some general maintenance catch up on the 2zz I purchase from a local salvage yard and of course the intake lift bolt was broken off. the rocker shaft was slightly rotated in the head not allowing for any type of extraction so I went with the Toyota TSB style removal of by sliding the shaft itself out. It's on a stand so access to everything was no problem but I had to beat the hell out of the shaft just to get access to the lift bolt. So bad it ruined my 3/8 extension and the shaft itself. Again no choice since the shaft rotated and a 1/4 of the lift bolt was under the casting. I did manage to get it out but the lift bolt gouged the head pretty good in the process. Solid 1/32 deep channel in the casting on the cam gear side. On top of that the other end mushroomed a tad damaging/scratching the bore a bit all the way through. I just wanted to see the sanity of my plan to try and wrap the end of 3/8 steel tubing I have in emery cloth and deburring the bore. Then just put in a new shaft and call it done. Of course I'll flush everything well before it gets sealed up. I am assuming that as long as it's clean the damage won't harm anything since it's really just a channel for oil to get to the lifters. Any seepage through the damaged channel would just leak out into the timing chain area. Or am I missing something? Anyone experience this?
 

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So I went to just reseal and do some general maintenance catch up on the 2zz I purchase from a local salvage yard and of course the intake lift bolt was broken off. the rocker shaft was slightly rotated in the head not allowing for any type of extraction so I went with the Toyota TSB style removal of by sliding the shaft itself out. It's on a stand so access to everything was no problem but I had to beat the hell out of the shaft just to get access to the lift bolt. So bad it ruined my 3/8 extension and the shaft itself. Again no choice since the shaft rotated and a 1/4 of the lift bolt was under the casting. I did manage to get it out but the lift bolt gouged the head pretty good in the process. Solid 1/32 deep channel in the casting on the cam gear side. On top of that the other end mushroomed a tad damaging/scratching the bore a bit all the way through. I just wanted to see the sanity of my plan to try and wrap the end of 3/8 steel tubing I have in emery cloth and deburring the bore. Then just put in a new shaft and call it done. Of course I'll flush everything well before it gets sealed up. I am assuming that as long as it's clean the damage won't harm anything since it's really just a channel for oil to get to the lifters. Any seepage through the damaged channel would just leak out into the timing chain area. Or am I missing something? Anyone experience this?
Good luck!

I had same broken "lift bolts" on my Detroit Nasty and hammer the end of the rocker shaft to the point I had to replace it. It was a good learning experience....and the engine/head was not in the vehicle!

Mr. P
 

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Good luck!

I had same broken "lift bolts" on my Detroit Nasty and hammer the end of the rocker shaft to the point I had to replace it. It was a good learning experience....and the engine/head was not in the vehicle!

Mr. P
Adding: Rocker shaft does not rotate. De-burr at will, but no need to worry about the bore as this shaft does not rotate unless rocker bolts fail.

In my case, I just purchased a new rocker-shaft.

In unrelated issue, also purchased intake cam assembly and it inlcluded 4 rocker followers! My cam had some striations and 1 of the 4 "lift" cam followers had wear.

Mr .P
 

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Discussion Starter #5
If this motor fails due to the damage I'll just seek another 2zz then. I'd only be out some new seals, spark plugs, and a rocker shaft. Well worth the risk and cost. The rockers themselves look great and took zero damage as I didn't force the mushroomed end all the way through. After I took out the lift bolt I filed and cleaned that end of the shaft up and ground down that extension that I already ruined to fit in the end of it. That way it was pretty clean going back through. OK I'll order some new parts and focus on keeping material managed and out of the oil circulation. Thanks for the pep talk.
 

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If you can deburr the hole enough so a replacement shaft sides in and out nicely and fits without any wobble, you should be ok. There will be a little extra oil flow through the VVL system when lift is engaged, so the only issue you could run into is with it getting into and staying in lift if there is not enough pressure to lock in the pins for the big cam followers.
 

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I had a similar but not as severe issue with my JDM 2zz when I got it. Had to hammer the shaft out with broken lift bolt in it... Deburred and made everything as close to round as I could, reinstalled and it's still going after 20k miles. In your case I agree a new shaft is in order, but think the head can likely be salvaged. Worth a shot.... It either works or doesn't.
 

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Discussion Starter #8
So just an update on this one in case anyone stumbles on it with the same issue. 3,000 of very hard driving and zero issues. Everything sounds tip top so it was sure worth the gamble.
 
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