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Ps... Anyone out there willing to lend me a Crain to get the block out?? Will sort a deal forsure!!

As a few may know I messed up my timing belt. Heads off, #2 claimed both intake valves witch snapped off... And hacked up the piston top... Boar seems good at this stage... How's the safest way to clean the shit out?? Top that piston and blow it out? And what do i need to know about piston removal?? Am I getting 6 freshies? Cheers boys!

Edited by chef_stagea
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Got pics of the piston? At this stage I'd be taking the motor out mate, you're gonna have to take off the sump to gain access the crank/rods so you can remove the rod bolts and then push the piston out through the top. Then I don't think it's gonna be as simple as dropping in a new piston. You've got clearances to worry about, etc. Looking more like rebuild territory from the info you've given. That or a replacement motor

yeah without pics of the severity of the damage, I'd say Luke's on the money

you'll need to remove every bit of debris out and if there's anything caught between the cylinder and top ring land, good luck getting it out.

Also, any damage to the bore (below top land) will cause you grief unless addressed......you'll be surprised how even minor bore damage can affect the top comp ring

Yeah ok... So basically rip the engine out n go from there... Why is it not possible to just replace the piston? I'll put pics up of the boar tomorrow. 1st thing I need to do is drop the auto box off!!

I've already brought a new head. Getting cleaned up and port and polished too. So I'll avoid new engine. For that reason. Money and rego/numbers bullshit.

When you say rebuild what are we talking.. Full bottom end sent away?

There's all tiny bits of valve everywhere... So there would be shit down there!

The guy I got the head off has the bottom end ( cyl seized) maybe I should grab that for parts???

I'm not 100% clear y I can't just change the piston top to a stockie... Or just not Gna happen?

  heslo said:
Winner winner, chicken dinner
  chef_stagea said:

Yeah ok... So basically rip the engine out n go from there... Why is it not possible to just replace the piston? I'll put pics up of the boar tomorrow. 1st thing I need to do is drop the auto box off!!

I've already brought a new head. Getting cleaned up and port and polished too. So I'll avoid new engine. For that reason. Money and rego/numbers bullshit.

When you say rebuild what are we talking.. Full bottom end sent away?

There's all tiny bits of valve everywhere... So there would be shit down there!

The guy I got the head off has the bottom end ( cyl seized) maybe I should grab that for parts???

I'm not 100% clear y I can't just change the piston top to a stockie... Or just not Gna happen?

Alot of questions there Adam.

Firstly, to remove a piston from the top, you need access to the bottom end, hence why engine should be removed.

If there are bits everywhere, more than likely the above will need to be done.

If the guy's bottom end siezed, don't touch it!!

Hopefully that answers most of your queries

EDIT: If you remove the piston in question and it looks OK once you've cleaned all the shit out, there maybe a case for using it again......if the piston is damaged however, changing just one piston may also be a possibility. Without sighting anything though, we're pissing in the wind unfortunately.

Ok don't want to confuse the situation here...

My piston #2 is hacked badly! Not usable at all. I can get a good 2nd hand one for 100... More than stock i no so I'll get onto that...

Engines coming out. f*k re-assembling in the car,

I'll get some pics for you all tho.

  SLED said:
Alot of questions there Adam.

Firstly, to remove a piston from the top, you need access to the bottom end, hence why engine should be removed.

If there are bits everywhere, more than likely the above will need to be done.

If the guy's bottom end siezed, don't touch it!!

Hopefully that answers most of your queries

EDIT: If you remove the piston in question and it looks OK once you've cleaned all the shit out, there maybe a case for using it again......if the piston is damaged however, changing just one piston may also be a possibility. Without sighting anything though, we're pissing in the wind unfortunately.

you really should balance the new piston the to other 5.

Since you are going to have the engine out i would whack some rings and bearings in it and perhaps give it a light hone. It will cost you a couple hundred more and then you will have a fresh bottom end.

whats wrong with being centered Dan??? i am contemplating rebuilding my old RB25 and well that has the same as what adam has done to his.....piston-valve loving.....should be a good way to learn more about the beloved RB25

  D_Stirls said:
you really should balance the new piston the to other 5.

Since you are going to have the engine out i would whack some rings and bearings in it and perhaps give it a light hone. It will cost you a couple hundred more and then you will have a fresh bottom end.

yeah, as Dale said Adam.

If your pistion is totally stuffed, I'm guessing it's also had an effect on your cylinder......which will then need to be bored along with the other cylinders (plus new oversize pistons & rings).

Even if the bore has not been marked by debris, you'll still need new rings for that second hand piston and at the very least, have it lightly honed (and ridge removed if any to avoid top ring damage) otherwise the rings for that cylinder won't bed in & therefore won't hold compression or control oil blow-by.

  Damo_R34 said:
sounds like a perfect candidate for a 30 bottom end!

would love to damo but i just cannot afford to go down this track...

truth needs to come out :thumbsup: the belt that was in there was only 10k old!!! but i allready had it off b4 i knew!! anyway

yes i post on an iphone sometimes, it wont let me select the screen so i have to use a special item tool thing.

here some pics anyway...

i think ill just f**k this engine off, the 34 neos obviously RWD... is it a matter of putting the stagea sump etc onto it and off i go?

im going away friday, but will let you know about the crain and stand. but that would be amazing!

the boar doesnt look too good in that pic, bit it feels smooth.

post-47249-1282705397_thumb.jpg

post-47249-1282705418_thumb.jpg

post-47249-1282705437_thumb.jpg

post-47249-1282705542_thumb.jpg

Edited by chef_stagea
  chef_stagea said:
i think ill just f**k this engine off, the 34 neos obviously RWD... is it a matter of putting the stagea sump etc onto it and off i go?

Not as simple as that IIRC, don't think a RWD can be converted to AWD

  craig R33 said:
would have been even cheaper if he let an experienced person replace timing belt....

lesson learnt?

Most definitely!

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