Looking at the wrist pin pieces, it doesn't look to me like this was the root cause. I would expect the pin to be clean cut by the scissor forces between the piston and rod.
However this pin looks like it's been through a blender, meaning that the pin was dislocated before it broke, probably by the crank. I would like to see the piston and rod of that cylinder.

Oh crap! now were going pout? There is no difference to passing on a discussion about you from a friend of mine that told me you balanced his tires and his wheel broke and came off. What was lost in translation was he hit a curb first and broke the damn thing.

Or Jake supplied engine parts that caused a guys engine to fail only to dig into the subject deeper and find the guy assembled the engine with a pipe wrench in a gravel pit.

We should all be careful what we say about any business. Thanks for taking the time to post but it would be nice if you based your post on facts. That's all I'm saying. Here we are several pages into a post flaming a company and we still have no other examples and no conclusion of forensic testing on a 2009 post. One thread on one forum.

I have to disagree. That wrist pin SHATTERED. Most likely it was overhardened and brittle or just plain crappy metal, or even worse it was cast and full of voids. Had this been a decent part that had sustained secondary damage, I would expect only one or two pieces, and curled edges where it bent before snapping. These hard straight edges look more like the whole thing just shatterd like a glass

While I'm at it, all of you children need to take a time out.

The picture is from a 356 Registry forum, and is of an entirely different incident. I have no pictures from the incident related to me by the folks at CE. There are multiple unsubstantiated (and undocumented, to my knowledge) reports of other such "events".

The Cap'n

I've got a set of AA's 96mm P&Cs sitting ready for my 2056 build.
Are they worthy?

Do us a favor and pull one of the pins and look inside to see if there is a mis-match in the bore or something. A rockwell test may be out of the question as it would mark the pin. But based on the number of incidents posted with actual photos, (one from 2009?) I'd use em.

BTW: I'm putting myself in time out. No not really..

Cant the side be hardness tested?

I'll post a picture later tonight.

Ah, They will be fine! Tick,Tick, Tick, Tick

Seeing how there doesn't seem to be anyone willing to back up their BS I sent an email to the guy that posted about the pin and never followed up the rockwell results. From 2009....

Anyone else think that's alot of pieces for one pin?

The thickness of that pin looks too thin, too.

It also looks like more than one pin. There are far too many pieces there for one pin. I could be wrong. Hell I could be wrong about my whole position. Naw, because my position is no one has shown any real failure. The only thing that has been stated are internet legends and stories of hearsay. I'm just looking for facts.

The pin is discolored and appears to have been running dry. Look at all the spin marks and galling on the pieces. That thing is ground to snot. Even Jake would have to admit if he pulled down an engine with a couple thousand miles on it and the pin was galled like this one and bluing was evident there would be a bigger issue here than the pin itself.

I told you I was going to email the guy on the 356 forum and find out what he know about the test results from the Rickwell test.

Here is the response from the 2009 post on the 356 forum.

"The Rockwell test showed the pins to be much higher on the C scale, hence more brittle, than either Mahle or NPR. I do not remember the numbers. The Chinese pins were also thinner and weighed less. No other people have reported the same failure, but I do not use Chinese parts anymore."

Here is the Rockwell class info:

HRC . . . . Steel, hard cast irons, case hardened steel and other materials harder than 100 HRB

HR-"C" is as stated above

HRD . . . . Thin steel and medium case hardened steel and pearlitic malleable iron

Harder than "C" is for thinner steels like lighter thinner pins.


Then I asked:

"Was there any mention of the galling and bluing discoloration on the pin? The photos seem to show a bluing and dry running condition. I was just wondering if this was ever considered or looked at as a contributing factor. There is another guy stating he has had a pin fail but presents no facts to support it. Your case is the only other one I could find with any real evidence or consideration for testing beyond hearsay."

I have not had a response.

So, everyone's experiences and opinions are BS to you until they provide a metallurgy report of the parts in question?

By the same logic, all *your* posts should be treated as BS as well since you haven't provided any proof whatsoever that refutes any claims made in this thread.

people can draw their own conclusions

Rick you don't have to stop using AA parts

The captain will stop using them
and I will also avoid them based on my respect for the advice of Jake and John...
(two people who always lead me in the right directions and have always given me good advice.)

P.S. the biggest type4 builder in colorado won't use them either. He stopped using them years ago. He recommends keith black if on a budget.

when you make an accusation about a product failure and base your opinion on hearsay, ya, that's BS.

I am attempting to gather information and continue to ask questions. I have followed up with the leads presented. If that's BS then so be it. I'm not a lemming. I don't just take someone at their word because they have owned wrenches and bolted together some car stuff. Oh wait, let me get my flute and play you all a tune.

Ya, that was intended to be stark and frank. Ban me.

Your talking about the reputation of a company that makes parts we would like to have the confidence to use. So if it makes you uncomfortable for me to ask for facts to support someones position that's too bad.

If your fine with the condemnation of parts without proper testing then so be it.

You of all people should see the wrong headed thinking here. You deal in facts everyday.

What i see is someone trying really hard to disproof a claim made here. That's not looking for the truth or facts.
You don't come across as impartial.

Let me ask you this, just hypothetical:
What if it turns out the Captn and Jake were right?

Would you admit to that?

Really? How old are we now? 12?

Yes Andy, I will gladly admit that I am wrong. I'm big enough to do that.

I'm not the one that came here saying there was a failure of a wrist pin and all AA parts are bad.

I'm not the one saying I had a car with a used engine with AA P&C's and had a failure that I was claiming was from the wrist pin.

I'm the one asking for facts to back it up. All we have is a 2009 post with questionable photos and one guy saying he has a buddy with a claim.

I'm the one looking for all these other tested failures.

Can we base a decision on facts or should we just settle because the captn and jake say so..

I'm not even saying those guys are wrong. They just provided incomplete information. I'm just asking for facts.

Anyone else have any leads?

And the ban me comment was intended be sarcasum. Whatever.

http://www.lmgtfy.com/?q=site%3Aporsche356...ift%22+rockwell

Which will lead you to this:
http://porsche356registry.org/356talk/1/12437.html

The debate (as I see it) isn't whether or not a set of AA pistons failed. It's the assertion that, "We should all stop using AA pistons because they are likely to fail and destroy your engine."

I believe that statistically there will be failures, and the number we have seen fall squarely into that.

It happens.
It SUCKS!
But it's not a sole reason to condemn a whole product line.

The AA pins I have here are 4.2mm thick and weigh 135g.

I wondered if the wrist pins got dropped prior to assembly. Regardless of the application, I avoid using anything made in china, if at all possible.

Maybe it's my lack of understanding of the English language, but to me, your posts don't come across as someone "just asking for facts".

To me, your posts seem to have a very personal note to them.
Like i said, you don't sound impartial.


Maybe i'm off-base here (wouldn't be the first time) ...

Nice link. Thanks for posting that. It would be interesting to see what the grain structure looks like. I have seen grain structure analysis and have a claim I am working on now involving a failure of a fitting. That's is a great way to make a valid determination. I would if there was ever a conclusion to that part of the discussion.

Digging deeper for the facts and it was nice to see that someone has access to serch that site for more info.

But ultimately Mark is the most right here. Parts fail. I had a cam shaft break. A Porsche Cam shaft not a cheap knockoff or welded up regrind. It cost me thousands and thousands of dollars. Should I stop running Porsche cams or consider it a bad day in the life of my hobby. (more like a bad couple times )

We still only have 1 claim that appears to have any eveidence supporting the pin failure from 3 years ago when thousands and thousands of these sets are in service. Shit happens.

Come on Andy What's my history here? Do I go out of my way to bust someones balls? I just don't like it when people come here and start product bashing or vendor bashing without foundation.

I'm not inocent of it either. This time it just rubbed me the wrong way. One guy say's something then another legend is spun then the lemmings start chiming in. When in reality like I've posted hundreds of thousands of these sets are in service all over the world with no other cases coming to bare.

Just got done reading this thread and I have to agree with the idea of putting forth information for that sake alone and not blanket conclusions condeming an entire product line or company based on limited data. Most parts are made in batches, by different opperators, at different times and under various environmental conditions.

Even the porsche factory has had problems which required recalls and even numerous entire engine replacements due to lubrication problems (the 996 as an example). It is the nature of manufacturing ....... if any entity does not make mistakes or have any variations, then they are not doing or making ANYTHING!!!

As Rick mentioned 'stuff happens' to even the best parts and no company is immune from variations and or defects. As most already know, there are a lot of factors that can make a part fail and sometimes the cause is not always the fault of the failed component. Judging by the amount of AA piston sets that are in current use vs. the ones that have suspected issues, it would seem there is not enough reason to shun them entirely.

Intresting read for sure.

Hardness of the pin is one issue. I believe not to long ago someone lost an engine to "bad" gas.

I know quality can be lacking with some manufactures, no one has a 100% track record of success.

Seems to me that a prudent person would take the data, and use it to minimize the likelyhood of their parts failing. IE - Check the hardness. I believe it's also done to Cams, Lifters, etc. etc. etc.

The Type of ATV I have, others had issues with failed wrist pins. Seems it was a perfect storm of too brittle heat treat, High RPM and a tad to much advance. Solution was check the pins, lower the RPM 12,500 to 11,500, and remove a touch of timing. Problem solved.

Like Jake says, "I'ts all in the combo."

Thanks Capt and Jake for the information and others for their contribution.

Smitty

Anyone have a set of AA pins we can have a Rockwell test done on? My friend Cass has a Rockwell machine. I'm not sure it's in "C" as his book states it's in "B" but even if it isn't in "C" I work with several forensic engineers and could have a test done. If there's a cost I would be happy to cover it to settle this issue.

I have a set of stock 2.0 pins and a set of stock 1.7 pins to compare.

Based on Mark's measurements the pin doesn't seem to be the same one as the 2009 post. It's thicker and heavier.

Based on those hardness figures I'd say the Mahle pin is at the low end of the correct hardness range and the NPR pin is at the upper end of the correct range for wrist pins.
The AA pin number indicates the lack of (or improper) tempering after the initial heat treat - or the wrong alloy.
61C Rockwell is good for cutting tools which need to hold a sharp edge.

Thanks for posting that Chris. Again, based on what McMark posted our AA pistons don't use that same pin as the one tested in 09. Do you have any AA pins in your shop so we can run a Rockwell test?

Also, based on the photos does that 2009 pin look like a part that was functioning as it should? I have a wrist pin on my desk that is clean and shiny not galled looking. The photos make the pin look galled as if it was run dry and it looks like it has a bluing as if it was quenched. That would change the hardness. I realize I'm just looking at photos and not the real part but there seems to be more to the story that was not taken into consideration in 09.

All things considered, catastrophic failure at 100 miles, well within the break-in period, is simply unacceptable, especially with other (albeit anecdotal) evidence out there that this is not an isolated incident. I mean, if you'd just spent $11K on an engine, would you abuse it during the break in procedure? The manufacturer's representative's "take a hike" response is also an obvious case of CYA and clearly a defense against setting a precedent that could bankrupt them. I care not what you do, I'll never buy, sell, or install another set of AA pistons and cylinders. I may be a lot of things, but I'm not a slow learner ..........................

The Cap'n

Come on now.. Look at the results. It's not even the same pin as the AA P&C's were buying. I've offered to send a pin to a forensic engineer to put this to rest. If I don't get on offered up I'll buy a set of P&C's and send the pin in for testing. How's that?

Cap'n ask your frind to supply a pin from the rest of the set so we can have it tested instead of condeming the parts right out of the gate. There's a productive solution.

Rep's do things like that. I had a DuPont rep that had an excuse for every product failure we had. We were regularly used as guinny pigs in the industry and it cost us thousands in repaints to protect our reputation. Anyone in the industry that used DuPont knows about the horrors of Cronar!

no second hand speculation here...

I have several hyped up type 4s running around with AA 96mm pistons. 10 of these customers flog their car as hard as me and Herb flog the 10jreen. the 2.4 with 103mm AA slugs broke teh crank after 3 seasons with 2 drivers, AX and TT DE. that was my fault because I did not flag bad machining on the journal raduius. it did not blend to the tang but was cut .002 below the journal surface.
the pins and pistons are OK

AA piston and jug machining must be CAREFULLY QC INSPECTED AND MEASURED. I reject about 1 of every 12. 2007-2008 was higher reject rate. no rejects since june of 2011 or 5 sets.

no issues with grant rings yet but I gap them
I do not use hone pattern that comes from AA
I polish ALL SHARP EDGES ON ALMOST EVERYTHING

Thats good to hear. It seems only a few failures get everyone talking but no one talks about the successfully repaired or upgraded builds using lower cost parts. Not everyone has 3k to spend on a p/c set so the market is there and I'd bet there are way more of those running the roads than the high-end boutique builds. Both should and will work and both could fail. I would not have an issue using an AA set on my motor if I needed to build it on a budget. The success stories arent talking because they're too busy driving

No AA samples for testing here.

I agree that the pictured pin shows signs of unusual wear, but I didn't notice any clear evidence of overheating.
I'm pretty sure that pin was bad from the mfr, despite any evidence of abuse while in service. Overheating from running dry shouldn't cause the pin to shatter.
No amount of detonation should be able to fracture a wrist pin before causing serious damage to the piston and rod/rod bearings.
Rockwell 61C hardness is just wrong for a part which needs lots of toughness combined with wear resistance.
Numbers in the low 50s would make me happy, along with alloy composition intended for such usage, ie. precision machining, wear resistance, and impact toughness.

...I would prefer to use OEM cylinders bored out to 96mm with KB or JE pistons but few pony up for that, not even me.

I tried to smash a pin with a sledge. it did not do "that"

I like Sean's method of testing! So that leads us to our pin size and weight and the need to rule out an across the board part defect.

If anyone has a pin they want to send me I would glady have it tested and post the results.

I am certainly no expert - I am only on my second 914. My last one was a 2056 in which I used KB 96s and re-bored stock cylinders with SDS. European Motorworks sells a 96 cast iron cylinder for $50 each. Pair those with KB pistons and your into it for $380 not much more than AAs - might be a good alternative - I am looking to possibly go that route on my current build

I have a set AA of pins along with 96mm cylinders and pistons. I just picked up a set of KB pistons to use for a 1911 build so I'm not going to use them. I may have access to a rockwell tester if not I'll send them your way Rick. Since it's my first time building a type 4 this post is very helpful to evaluate what parts I'll use for my build. I also have a few sets of 1.8 cylinders that I may now want to bore out in place of the AA cylinders. Can someone chime in on what to inspect for imperfections on the cylinders? Is the material inferior, is it the casting, or machining?

Thanks,

Jsaum

Thanks for posting this. If you don't have access to a Rockwell test let me know. I'll PM you my address. If you want I'll pay your shipping or what ever.

Also If you don't have someone local to properly bore your cylinders I think I read Chris Foley has a proven way to get that done.

I wouldn't use Rockwell C scale on a wrist pin that I was gonna put in a motor.
15T is better but buff out the divot. Don't forget to get a chart for taking the diameter of pin into account or you'll get a bogus reading. The shattered pin pic was cool. Looked like glass....or RC61 steel.

Back to lurking on this thread.

I'm working on it, but not ready to go commercial yet.

I know AA has a decent rating in the type 1 world, there were a couple of mishaps, but a lot of guys also chimed and said they drag race/used aa pistons and had no problems, I almost bought a set but found an entire engine instead.

Thankfully, nobody has come forward with a claim that George Hussey personally built a motor using AA p/c's and installed it in a stolen, rusty 914 prototype that blew up in China because the pins seized due to the K&N filter, Pertronix, and not using Brad Penn oil.

Just to add some fuel...1.7L with 96mm AA pistons. I bought te car in 94 and put on well over 150,000 miles in 15 years, 10 of those Auto-x and daily driver. Rebuilt bottom end at 100,000 to repair detonated lifter.

Stopped putting oil in the car a year before I stopped driving it becacause i was too lazy to repair the push rod seals. Switched to mini van when 2nd child was born. Still had over 100lbs of compression.

Would do it again.

Thanks!! I needed that after today.

I interpreted the original post as a red flag regarding AA's response to a Walt's problem with one of their products. I don't require any forensic science to tell me that a company with no respect or concern for an experienced pro certainly won't work with me if i should have any problems with any of their products.
I appreciate the heads-up from Crusty.
While I agree failures happen, blatant disregard for the customer is inexcusable.
Weather or not it was the cause of the failure, I'm curious to know if AA knows or has a quality standard for the Rockwell hardness of the wrist pins they sell.