# chicken and egg



## RKTuning (Nov 7, 2005)

Expert opinons on these pics of a RB26 piston and rod.
all happend in 1sec exactly 60knock and then nothing just dropped onto 5 with no horror noises






as you can see bearing perfect and infact still turned on crank smooth.
The other thing is there seems to be no large pices of rod to be found!!!
never seen anyting like it, before has anybody else seen anyting similar


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## fourtoes (Feb 27, 2003)

Casting fault?
Bob


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## RKTuning (Nov 7, 2005)

They have done alot of hard miles though Bob!
all other pistons and rods are perfect


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## minifreak (Mar 4, 2006)

Holy shit Ron!


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## RKTuning (Nov 7, 2005)

minifreak said:


> Holy shit Ron!


Yea he wants his money back Greg LOL


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## minifreak (Mar 4, 2006)

Lol I'll give him his money back for that one  he's welcome to anything on my trolley! Lol


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## Jimefam (Apr 30, 2011)

I've no idea what happened but out of curiosity, it seems to be tomei pistons and what type of rods?


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## RKTuning (Nov 7, 2005)

unkown I beam from Japan
reved regulary to 8700rpm on std crank


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## RKTuning (Nov 7, 2005)

There is no reason for questions other than curiosity to find what broke first.
we think piston broke under gudgen pin


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## minifreak (Mar 4, 2006)

Have you found all shards of metal from the missing bits? I'd have thought Rod as the pistons broken bits look clean as if the rods smashed the piston to pieces.


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## RKTuning (Nov 7, 2005)

minifreak said:


> Have you found all shards of metal from the missing bits? I'd have thought Rod as the pistons broken bits look clean as if the rods smashed the piston to pieces.


All piston parts found but very few rod parts, seems to have vanished


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## minifreak (Mar 4, 2006)

Was the pin still in the top side of the rod? I'd think that if the rod broke it would easily destroy the piston, but if the piston broke then there would be less impact to snap the rod where it's broke. Just thinking logically, you know my engine knowledge is limited ;-)


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## ANDY H (Mar 17, 2005)

how much bore damage?


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## Sub Boy (Jan 28, 2008)

I would think (lack of knowledge here) that it would be a rod failure, the ring lands are intact and the bearing surface is fine


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## GT-R Glenn (Nov 9, 2002)

Theres lots of answers I suspect
It does look like the piston has sheared off under the pin (or something similar) it is a very unusal looking break, almost like it has developed a crack which has passed around the circumference eventually breaking the lower section off.

The rod is pretty unique looking too 
Snapped BOTH ends off !!

All in all 
10/10 for effort


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## jaycabs (Nov 16, 2007)

maybe im looking into this to much but when you look at both ends of the snapped part of the rod here 











looking at these 2 ends to me i think suggests that it did let go at the piston because if it let go at the rod then i doubt it would have such a consistent squash on each end of the rod meaning that the top of the rod has hammered the piston when it let go giving that even compression before the rod finally let go in the middle section one end at a time plus like andy h said ... how much bore damage ??? does it look at all like the rod has dug into the bore after one point snapped ?


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## black bnr32 (Jan 20, 2011)

I'm confident the piston let go first, and a crack developed over time starting at the location circled in red:



















then the rod smashed into whatever it could, first breaking at the piston end (probably with the wrist pin still in). after that broke, with the crank still turning, the broken end smashed into something again and broke at the big end.


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## tonigmr2 (Sep 12, 2002)

Gudgeon pin ripped out of the piston? It's a common worry for a failure point on some of the higher revving 4age's. Just thinking what you said about the revving.


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## RKTuning (Nov 7, 2005)

jaycabs said:


> maybe im looking into this to much but when you look at both ends of the snapped part of the rod here
> 
> 
> 
> ...


The bore is hardly marked, maybe a small groove were the pin had scraped up it. The piston was jamed half way up because it had twisted and cocked sideways.The datalog showed 60 knock on that cylinder for 1sec so that is all it took to wipe the rod out completly at 6700rpm.
The other amazing thing is 90% of the rod beam is missing? and yet all of the piston pieces are there
STRANGE!!!!!


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## Miguel - Newera (Sep 18, 2003)

Depending on where it was bought from, there's a small possibility the Pistons were fake Tomei.
There have been a number of parts replicated in S.E. Asia that then appeared on the market as cheaply priced Tomei goods. If they were bought from a supplier in Japan there's much less likelyhood they weren't the real thing, but from the States, Ebay, etc. it could be a possibility they weren't really Tomei manufactured. I'm not saying it's definitely the case, but perhaps an explanation.

Tomei's pistons are pressure forged aluminium, which are obviously stronger than cast. These do look forged, but then again the fake stuff that's been on the market does look very similar to genuine, so I don't know. You could try sending the Piston to Tomei and ask them to verify, perhaps - or I can alert Tomei's staff to see these pictures.

Some time ago there were a lot of fake Nismo N1 oil pumps in circulation, that failed soon after fitting. This could be a similar scenario perhaps.

It would be a first time I've seen a genuine Tomei piston break up like this, TBH. 
Have heard of a Tomei cam snapping, but that's from error in installation by the customer in not screwing the caps down correctly, but just starting at the centre. The quality of their engine components is usually spot on.


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## mattysupra (Oct 31, 2008)

Ron, have you taken this engine apart or someone else? 

How can the rest of the rod be missing? I take it that it must be smashed into small pieces rather than missing?

and how did the knock only hit 60? surely there must of been a hell of a noise while that was breaking up?


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## RKTuning (Nov 7, 2005)

Miguel - Newera said:


> Depending on where it was bought from, there's a small possibility the Pistons were fake Tomei.
> There have been a number of parts replicated in S.E. Asia that then appeared on the market as cheaply priced Tomei goods. If they were bought from a supplier in Japan there's much less likelyhood they weren't the real thing, but from the States, Ebay, etc. it could be a possibility they weren't really Tomei manufactured. I'm not saying it's definitely the case, but perhaps an explanation.
> 
> Tomei's pistons are pressure forged aluminium, which are obviously stronger than cast. These do look forged, but then again the fake stuff that's been on the market does look very similar to genuine, so I don't know. You could try sending the Piston to Tomei and ask them to verify, perhaps - or I can alert Tomei's staff to see these pictures.
> ...


I'm not after blaming a part but more to try and understand what happend.
they were genuine Tomei from RB years ago.
all other pistons seem perfect.


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## RKTuning (Nov 7, 2005)

mattysupra said:


> Ron, have you taken this engine apart or someone else?
> 
> How can the rest of the rod be missing? I take it that it must be smashed into small pieces rather than missing?
> 
> and how did the knock only hit 60? surely there must of been a hell of a noise while that was breaking up?


We took the engine apart and yes there were some small pieces of rod but not enough to make a complete rod.

60 knock was registered on the life racing ecu which normally only sees 5 max.
The rod did not make it's way outside the block


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## Miguel - Newera (Sep 18, 2003)

Sounds high. The knock could have contributed to the failure, perhaps. 
I'm sure you'll know better than most, Ron! :thumbsup:


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## Miguel - Newera (Sep 18, 2003)

RKTuning said:


> The bore is hardly marked, maybe a small groove were the pin had scraped up it. The piston was jamed half way up because it had twisted and cocked sideways.The datalog showed 60 knock on that cylinder for 1sec so that is all it took to wipe the rod out completly at 6700rpm.
> The other amazing thing is 90% of the rod beam is missing? and yet all of the piston pieces are there
> STRANGE!!!!!


Could it be the engine lunched the rod.... (mooan!)


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## Marky_GTSt (Dec 31, 2005)

Which cylinder was this ? im wondering if its heat related... My thoughts being along the lines of hot/cold cycling like you might see at the front of the block near the thermostat.


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## RKTuning (Nov 7, 2005)

Miguel - Newera said:


> Sounds high. The knock could have contributed to the failure, perhaps.
> I'm sure you'll know better than most, Ron! :thumbsup:


the Knock was the noise of the rod trying to escape.
no det on pistons


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## RKTuning (Nov 7, 2005)

Marky_GTSt said:


> Which cylinder was this ? im wondering if its heat related... My thoughts being along the lines of hot/cold cycling like you might see at the front of the block near the thermostat.


No4 so that blows that theory


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## RKTuning (Nov 7, 2005)

black bnr32 said:


> I'm confident the piston let go first, and a crack developed over time starting at the location circled in red:
> 
> 
> 
> ...



Thats what we agree on but does seem a strange break


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## mattysupra (Oct 31, 2008)

if my calculations are correct, the knock been recorded for 1 second still equals to the rod going up and down 111 times in that bore in 1 second? 

Is that correct? my maths is bad and that number seems way to high? 

If my maths is correct then it is understandable that there wont be much left of the rod? Most rods end up on the outside of the engine with a failed bearing so maybe as that is not the case here that the rod has simply broken up into many small bits? 

Has the oil pump and oil filter been inspected yet? maybe most of the rod is in the oil filter :nervous:


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## Marky_GTSt (Dec 31, 2005)

RKTuning said:


> No4 so that blows that theory


So your completely dismissing the idea that its heat related based on the fact that it was a cylinder not near the thermostat ?

and you can see absolutely nothing else different about no4 ? it got the same air flow, fuel, comp ratio etc ? as all other things being equal which they most likely where it does somewhat start to look like a simple mechanical component failure. which doesnt need much explaining really does it ?


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## blue34 (Jul 28, 2005)

So the Knock reading for 1 second was the rod failing. If most of the rod material has vanished then it must have somehow shattered. Normally any remaining length would end up knocking a hole through the side of the block. The sides of the piston look good so it obviously hasn't seized. And you say the crank journal is still ok? 

It almost looks like something stopped the piston coming down and the pin just got ripped out. You say the piston was jammed?

Could it be a partial failure of the skirt allowed the piston to twist in the bore and jam and the crank kept turning and ripped the bottom out of what remained of the piston?

Still doesn't account for the missing rod material though? the bits must be somewhere lol!.

If the crank doesn't turn out to be bent and the block also survived to be re-bored then it's a miracle! 

Be keen to know if you do find out what hapened.


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## jaycabs (Nov 16, 2007)

Surely that length of rod missing couldnt have all been blended into small fragments by the crank spinning what was left of the rod ? Surely there would be some larger pieces too ? 

Plus the oil pick up couldnt have sucked up anything but grains/crumbs .

Out of curiosity are the turbo(s) ok ron ?

Reason I ask is because you said the piston was stuck cocked sideways , was there enough room for pieces to go past as a strong vacume is still being created from the exhaust still pulling through for that brief moment ? 

Maybe im thinking a bit too far fetched lol ???


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## black bnr32 (Jan 20, 2011)

RKTuning said:


> Thats what we agree on but does seem a strange break


agreed, but i believe that 'channel' is right near the area of highest stress (that the pin exerts on the piston on the intake stroke). there's likely a bit of a stress concentration in the area of that channel.

it would be interesting to do a finite element analysis of the piston.


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## signalr32 (Mar 21, 2011)

We saw this on an RB at the local shop like 4 years ago... The only difference is that the engine was killed ASAP and most of the rod was left. 

The mechanic at the shop said that the rod ripped the pin out of the piston. Then started to bash the piston back up. He said because of massive stress and a lack of oil running into the cylinder. So a couple of questions:

1.) Like asked already, have you flush all your oil lines and the turbo.. REALLY GOOD. The small particles of the rod will probably been sucked up through all the lines and is all over the place. 

2.) Check the oil feeds. Make sure its not blocked.

3.) Be lucky the rod didnt go through the block.

To be honest this can be chalked up to just pure randomness. For instance my Audi S4 every now and then drops idle and bounces a bit. The Dealer said they have no idea why, and that many S4's have been brought in for this very reason and couldn't justify an appropriate answer (And they love to charge to do any sort of work).

I personally would check everything out from top to bottom. Make sure the oil lines are not clogged. Check all your oil seals and so fourth. I would be scared that small metal shavings got into the seals and over time will fail. I am so sorry to see this happen.

Edited for spelling.. Sorry really tired.


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## adamsaiyad (Aug 23, 2006)

Reading this post and very interesting read indeed.
To know more would certainly be a bonus.
I would like to see pics of the crank journal of failure meaning ifs it no 4 piston no for big end journal so we can tell what the crank munched and didnt munch.
Then the bore of course we need to see that too cause based on the info the block is still ok.
My Theory far from being much of a engine specialist, but here goes.
Rod failed on downstroke totally probably weak already, and was made worse by compression and combustion stroke, which then left the rod fractured, it then split away in the center from the big end and left the piston floating half way in the bore, the next stroke beat half a rod onto a piston that was being FORCED down by boost pressure.
So essentially if the pin had pulled away from the piston where the piston broke under the gudgen pin then the piston should have marks consisten with the length of a gudgen pin bash on the bottom end.
but this piston has concentrated deep bashes in the center particularly where the TOMEI sign used to be.
Also the small end of the conrod where the bushing sits is deformed, this means that it was hit into or by something hence the other half of the rod hit it !!!!
The big end of the rod is smallened to a short rod section, are we sure there are no visible marks on the block where it rattled and roll to death all over ???
Surely it couldnt have broken clean and then gotten those compression marks from no where?
Im getting ready to be flamed but its ok we all learn together.


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## adamsaiyad (Aug 23, 2006)

Ps on side note that wrist pins looks like it has some stress (hot) spots on it where the brass bushing picked up, funny though it isnt across the full length of the small end journal meaning it was seeing more load on one side ??
If the rod was breaking or bending, then this looks like a proof that it would be flexing the small end to one side because of bending the center of the rod.....
So in herently also points to rod failure first.
If the wrist pin was clean shiny, then that would mean it pulled clean away from the piston skirt and was bouncing around with no spinning load or rotational load coming from the cylclic motion of the piston going up and down and wrist pin rotating inside a piston.
The marks look like they are around the full 360 Deg face of the pin on one edge of the pin.
Means the rod was still in motion attached to piston while the load was being placed on one end of the small end bushing, meaning the road was bent .
Either has been bent for a long time ??
Or was bending slowly because of a crack .


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## R32 Combat (Jan 29, 2004)

I think you need to send all the parts you have metallurgist and get a professional opinon.

I happen to know of a professor at Sheffield University who could help you.


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## R32 Combat (Jan 29, 2004)

I might suggest that the 4 holes in the piston where the skirt starts were the birth of this failure. It looks like it has been cracked for some time judging shiney portion.










If the piston skirt broke off, the piston would jam in the bore and the crank would pull the already weakened piston in half. The rod would then mash itself up.

There are not many forces involed to pull a piston in half.

Cyclic fatigue is the most likely cause.


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## Mookistar (Feb 5, 2004)

I told you you couldn't use the toffee fingers from those quality street you lined the engine bay with, as con roads. But you wouldn't listen would ya!!


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## black bnr32 (Jan 20, 2011)

R32 Combat said:


> I might suggest that the 4 holes in the piston where the skirt starts were the birth of this failure. It looks like it has been cracked for some time judging shiney portion.
> 
> If the piston skirt broke off, the piston would jam in the bore and the crank would pull the already weakened piston in half. The rod would then mash itself up.
> 
> ...


hmmm...this is also possible. good theory.


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## Hugh Keir (Jul 25, 2001)

Ron,

There has been no mention of lazy knock sensors, I know they exist.

Often thought there should be an easy way to test them with a spring loaded centre punch on the sensor retaining bolt to see what the knock level is.

Unfortunately they are not easy to get to, to perform the test, although it might be possible to make up a special tool to do this though.


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## adamsaiyad (Aug 23, 2006)

Hey come to think of it we had a subaru wrx recently that had some serious knock, we werent sure what it was sounded like piston slap but also like a big end knock.
Any ways we took it apart and the one half of the skirt just plonked out, it had been broken for a while and could have been fractured if the piston was dropped.
The hair line fractures cause a stress spot and can spread through the rest of the piston.
And these were CP pistons too.
I can only assume that this might have been the case on this motor too?


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## R32 Combat (Jan 29, 2004)

adamsaiyad said:


> The hair line fractures cause a stress spot and can spread through the rest of the piston.


A hair line crack starts at an area of increased stress, rather than the other way around.


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## lightspeed (Jul 11, 2002)

My money is on fatigue crack through the pin boss. Fracture surface on the boss on the left of the picture looks very smooth compared to the tearing fractures in other parts. 

I had a rod small end let go in a 4g63. Biggest bit left of the forged piston was the size of a 20 pence piece. Gudgeon pin wedged itself in the transfer box after exiting through the sump.


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## Infomotive (Oct 22, 2009)

Looks like the left lock has walked out allowing pin to ride out the side as shown buy witness marks of little end pin on piston and offset galling of little end bush fatigueing piston and leading to piston failure.
Jason


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## RKTuning (Nov 7, 2005)

Infomotive said:


> Looks like the left lock has walked out allowing pin to ride out the side as shown buy witness marks of little end pin on piston and offset galling of little end bush fatigueing piston and leading to piston failure.
> Jason


We came to the same conclusion this weekend 
Spot on i think Case Closed
Cheers Ron


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## freakazoid3 (Jan 19, 2008)

Infomotive said:


> Looks like the left lock has walked out allowing pin to ride out the side as shown buy witness marks of little end pin on piston and offset galling of little end bush fatigueing piston and leading to piston failure.
> Jason


Wow spotted nicely from those pics :thumbsup:


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## adamsaiyad (Aug 23, 2006)

nice one infomotive really well spotted.


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## GT-R Glenn (Nov 9, 2002)

Since when do wrist pins walk sideways out of a piston far enough to collapse the under side of itself ...
Also if the pin walked . why isnt there a corresponding mark down the bore ...

Good theory, but again It could have been anything


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## ANDY H (Mar 17, 2005)

so what did the rod brake on if theres no damage to the bore?


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## R.I.P.S NZ (May 7, 2004)

GT-R Glenn said:


> why isnt there a corresponding mark down the bore ...


Ron said there was a scratch down one side of the bore from the gudgeon pin.



GT-R Glenn said:


> Good theory, but again It could have been anything


Take a closer look at the pictures Glen, its clear to see the gudgeon pin hasn't been running in the middle of the piston, a huge amount of the boss on one side has no witness marks at all and the other boss is extreemly flared out on the inner edge which could only happen after the pin walked out of the oppersite boss. 

At the beginning of the thread I noticed the above and as I was reading through the thread I had a reply in mind as I have seen exactly the same thing with a motor that used teflon buttons on each end of the gudgeon pin rather than circlips and one disintegrated resulting in the same type of failier, I got to the last page and Jase had put down exactly what I was thinking, I agree 100%.

Rob


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## R.I.P.S NZ (May 7, 2004)

ANDY H said:


> so what did the rod brake on if theres no damage to the bore?


because as the pin came out and wasn't supported on both sides so the rod was trying to turn into a S shape hence breaking at both ends.


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## R.I.P.S NZ (May 7, 2004)

fourtoes said:


> Casting fault?


assembly and/or clip fault, you can see the pin has never really been running in the middle of the piston, 1 boss is like brand new on the outer 1/2 which is impossible if the pin is in the correct place, the clip must have come out very early on.


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## GT-R Glenn (Nov 9, 2002)

If the clip came out very early one then there would be an obvious mark down the bore wouldnt there ?
Not to mention a circlip flapping around somewhere during oil changes.
It is a good theory and probably correct, but no one will ever know for sure.
Also its pulled the bottom of the piston off, all very odd ...

One things for sure, its broken ...


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## R.I.P.S NZ (May 7, 2004)

GT-R Glenn said:


> If the clip came out very early on then there would be an obvious mark down the bore wouldnt there ?


It looks like its been running offset by about 5-7mm from day dot and it simply can't run there if the clip was in, maybe there was a little burr or a slight tight spot in the oppersite gudgeon boss which kept it there, who knows.

Over time or right before it blew (maybe it got hotter than normal for some reason), the pins just decided to come further out, put huge stress on the other gudgeon boss and rod, then right at the end the pin's come out enough to touch the bore giving Ron the marks he has.

The pictures actually very clearly show whats happened which is awesome, nothing worse than having something like this happen and not know what caused it.


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## Infomotive (Oct 22, 2009)

RKTuning said:


> Expert opinons on these pics of a RB26 piston and rod.


Glen. I fail to see how a half knowledgable person from any background couldnt figure out the chain of events. Maybe you didnt look at the pictures or read Rons first sentence?
Jason


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## GT-R Glenn (Nov 9, 2002)

Mmm, interestingly enough I did see that and I almost started my post with "Im no expert but I have an opinion"

Actually I have done a fair bit of failure analysis in both TPM³ & RCM systems but I still cant see anything conclusive in the photo's.

But like I already said, you could well be right ...

BTW, I managed to track down a couple of "half knowledgable people from anybackground" to consult the photo's and no one came to any conclusion ...Obviously they are stupid .....




.....


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## Infomotive (Oct 22, 2009)

GT-R Glenn said:


> Mmm, interestingly enough I did see that and I almost started my post with "Im no expert but I have an opinion"
> 
> Actually I have done a fair bit of failure analysis in both TPM³ & RCM systems but I still cant see anything conclusive in the photo's.
> 
> ...


Everyones logic path is different i guess and sometimes the obvious chain of events is missed.
Out of interest i put my mechanic to the test and asked his opinion from the pictures" the pin has been running off to the side..."
Then for a laugh got customer to draw their conclusion... yes he got it to.
One thing is for sure that happened over a period of time whatever logic you choose to use.
Jason


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## R.I.P.S NZ (May 7, 2004)

GT-R Glenn said:


> Actually I have done a fair bit of failure analysis in both TPM³ & RCM systems but I still cant see anything conclusive in the photo's......


So based on the pictures you think the gudgeon pin was running in its correct location and the circlip was present right till the bitter end and it only went walkies after the piston broke?


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## R.I.P.S NZ (May 7, 2004)

Infomotive said:


> One thing is for sure that happened over a period of time whatever logic you choose to use. Jason


And the circlip must have been missing for most if not all of that time?


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## Infomotive (Oct 22, 2009)

R.I.P.S NZ said:


> And the circlip must have been missing for most if not all of that time?


Certainly for a period of time, how long who knows.


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## RKTuning (Nov 7, 2005)

The gudgen pin has been touching the bore as it is worn curved and smooth on the edge
will take pic and show


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## RKTuning (Nov 7, 2005)

This engine has done 20-30 15min races (circuit races) and dyno runs etc till it met its end, It's been reved to 8700rpm (standard crank)2bar boost on T51Kai.
The pistons were s/hand when fitted to this engine so they have done well and proberbly still be fine if it wasn't for the circlip problem.

When i said no bore damage i meant in the bore , the rod had hit the bottom of the bore though.
I think it has been interesting thread to get peoples ideas on the damage without having to blame anybody at fault.


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## R.I.P.S NZ (May 7, 2004)

RKTuning said:


> The gudgen pin has been touching the bore as it is worn curved and smooth on the edge
> will take pic and show


Great be cool to see it.

The fact the pin is like that and the witness marks in the gudgeon bosses confirm it had been running for quite some time like that, very lucky indeed.


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## Infomotive (Oct 22, 2009)

RKTuning said:


> I think it has been interesting thread to get peoples ideas on the damage without having to blame anybody at fault.


Think it has been interesting too thanks for sharing.
Would be interesting to look thru rest of the engine and see if there is signs of problem occuring on other little end assys or if was just localised.
Pictures of pistons on rods could be interesting.
Jason


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## jaycabs (Nov 16, 2007)

Ron , did any of the fragments of the rod get past the piston sitting sideways and into the turbo ?


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## RKTuning (Nov 7, 2005)

First pic has rounded edge that had rubbed bore 2nd pic flat edge pin


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## R.I.P.S NZ (May 7, 2004)

From the witness marks in the piston pin bosses and the resultant damage to the pin, piston and rod, personally I can't see any way of comming to any conclusion other than a circlip came out very early on, the pin walked out a little, ran around 5-7mm off center for quite a while, then came out some more, the pin rubbed on the bore and in that position there was huge loading on the pin boss on that side and flogging of the remaining contact area of the pin boss on the other side (shiney area) resulting in twisting stress on the piston and rod which finally lead to what we see now.

But hey, its just a theory and "it could have been anything" :clap:

Rob


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## R.I.P.S NZ (May 7, 2004)

Did you find the circlip in the sump Ron?

Also the circlip in the above pictures looks like it has a curved "tail" on it and its not sitting quite right in that area?


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## GT-R Glenn (Nov 9, 2002)

Yeah, I don't know Rob...
But unfortunately it is just a theory and again, it's probably right.
I wasn't there when it let go and didn't see the high speed hi res camera inside the engine
Anyway, I thought Ron was asking for suggestion on what may have happened, I will assume the first 46 replies were from mere mortals that don't have as many failed engines to analyse as you do. 

But I didn't understand Jas's comment "I fail to see how a half knowledgeable person from any background couldn't figure out the chain of events."
So presumably the first 45 replies were from half wits that can't figure anything out ?

I always had a bit of respect for a few of those guys comments in the past, clearly now that I know of these peoples shortcomings Ill be better prepared next time.
One thing I did notice was you only had an opinion after Jason offered his theory & after Ron offered more info.


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## R.I.P.S NZ (May 7, 2004)

GT-R Glenn said:


> I will assume the first 46 replies were from mere mortals that don't have as many failed engines to analyse as you do.


Come on Glen, its obvious what your up to, you know my reliability record and your after a wind up from me, the pictures were very clear I thought and I have almost NO experience analising failed engines actually and am happy to admit it, but the ones I have looked at luckily its been easy enough to establish what has happened, show where any fault has lied and fyi, my warranty payout figure over 20 years is still at $0. 



GT-R Glenn said:


> One thing I did notice was you only had an opinion after Jason offered his theory & after Ron offered more info.


You need to read my very first post again and properly then, I didn't even start reading the thread untill after Jason had posted and if you don't believe I was on exactly the same train of thought as him well before I got to his post then thats fine with me.

Its not about Jase being first to reply with the correct theory, its about you not being able to man up and accept you didn't see it first and from that point on being able to just accept, give credit where its due, rather than, as usual, turning something simple into a drama and turning things around to make others look bad.

You missed what happened, no biggie to me mate and with regards to Jasons comments you'd need ask him about them.

Rob


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## Infomotive (Oct 22, 2009)

GT-R Glenn said:


> But I didn't understand Jas's comment "I fail to see how a half knowledgeable person from any background couldn't figure out the chain of events."
> So presumably the first 45 replies were from half wits that can't figure anything out ?


To clarify for you Glen, i was actually quite surprised by the insight of some of the observations. Some had picked up that parts of the piston were "failing" before the inevitable.
There is normally a chain of events in a failure like this and rarely happens in an instant. As in this case, the failure of the circlip for whatever reason led to what we see in those pictures and now confirmed by wear on end of pin etc.
I believe most people once they saw a logical explanaition were able to join the dots.
Glen,It is hard at times trying to figure out if your just trying to be difficult.
I havnt seen this type of failure before so was interesting to asses.
Jason


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## R.I.P.S NZ (May 7, 2004)

Infomotive said:


> Glen,It is hard at times trying to figure out if your just trying to be difficult.


I have no problem working that one out and I am going to answer before anyone else just to be sure I get undisputable credit for it


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## RonniNielsen (Jan 14, 2011)

opcorn:

Carefull! dont feed the troll!


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## R32 Combat (Jan 29, 2004)

Interest, look here!

Tomei Piston Set - Nissan Skyline RB26DETT | eBay

A cracked piston. Dropped on the floor!! Doubtful.


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