P7

very true - lots of people that are affected by this don't even know about car forums. VP of Marketing where I work had an IMS failure last week. His car (boxter S) was daily driven (summer and winter) with 230,000 kms on it (144,000 miles) - which suggests that higher miles does not mean the bearings are good which some people suggested before

ivangene

sorry guys, I know I went a bit "off" there. I know these damn IMS threads are about as popular as death, and I am in no way trying to generate fear. the thread is one of discussing a new option available for those who wish to replace thier IMS bearing. I dont want to go OT and start the fear generating hype. That has zero value. The above post also had zero value when attacking Jake and kinda pi$$ed me off... I am sorry...

lets keep it on topic and hear what the people generating the new product have to say about questions raised. That is of some benefit IMO

I for one am curious as to some of the claims presented. I think I asked about how a replacement could be made after a failure when failures normally chew up the the IMS gear center bearing mating surface.
there were also clearance questions raised...

for those interested in learing more - I think the thread still has worth - The LNE has been proven ????thousands??? of times to be a nice kit at a reasonable price. I have never heard any fit issues or alike - The stock bearings last and last too, or dont, but that is not what this thread is about

Brucechas

Ed, no appology necessary...most of us feel the same way as you! *smile*

Jake Raby

I still want to learn more... I still want top know how it fits without flywheel interference. I haven't seen the photos yet that illustrate it on a manual car. The area of interference isn't just a little bit.. My students saw that last week in person, they touched the parts too.

PelicanParts.com

It seems you may have missed my link earlier that shows the IMS we pulled out of the 31,000 996 I bought for $10K with a motor "knock". See link here: http://www.pelicanparts.com/techarti...ft_Bearing.htm

This is definitely a real problem with these engines - it's not imagined. It's very easy to find these motors with these problems.

-Wayne

juankimalo

When Barracuda did the IMS home made upgrade, his car had 105.000 km
He sent me the OEM bearing and the bearing support to copy the same as he did. After an inspection of his original bearing It was in perfect condition. No ***** wear, and perfect rolling without dissalignment.

http://soloporsche.com/showthread.php?t=33716

As I did the same same operation, but my car was only 37.000 km, my original bearing was perfect too.

But thanks to your information, we know that they suffer a wear, and the best thing is to replace them

ivangene

in that link his IMS shaft is WAY off center like he did not pull the chain tensioners??? how is it that he was able to get it back together and did he have to re-time tha cams?
seems to be some missing info because that is a problem, then its shown all together as if by magic it just "worked" ????

BruceP

I don't know why it's so hard for some people to grasp that a component quality issue can be one of consistency to specification as opposed to design. Given Porsche's financial problems at the time, uneven quality from a badly chosen or badly managed vendor would seem unsurprising and pretty typical of how these things go. It's odd that anybody believes a problem has to be absolutely consistent in every example in order to be legitimate. Manufacturers can only dream of that kind of consistency.

The fact that some cars are 'fine' actually proves that the design, at least, was viable. The fact that some cars are not proves that there was a quality issue with a component vendor. The logical fix, therefore, is an improved component.

The only fly in this soup is that there's no cheap way to predict whether you're going to need it. At the end of the day, that's the only real basis of debate, here. Some people rationally play the odds, and some people prefer insurance.

juankimalo

Ha ha

You hit on the nail!

Barracuda is an amateur mechanic . He did it at his garage at home.
He didn't fixed the chain tensioners well. Then when he would finished the complete operation and starting the engine on, he realized that It was working in a single half engine. Turned it off, phoned to assurance and toe his car to Marbella (Málaga) 110 km far from his home (La linea, Cadiz). Then they did the adjusting Job of re-timing chains. New oil needed again... It increased the price.
After that he is enjoying his car and made more than 10.000 km without any problem

It was incredible! In our Soloporsche national meetting he told us his experience and gave us lots of details.
Imagine more than 20 people listening to an interesting technical conversation based on a rare never heard before IMS bearing upgrading!!!!
There were several mechanics in that meeting who were astonished to hear him.
He decided to do this, using his logical reasoning and stretching his brain (sure this is an incorrect expression of my poor english). He asked Porsche to replace that problematic bearing and they told him that this was impossible. But he tried to do it when the clutch service arrived. He built his own extractor and the rest is well exposed in the link. Perhaps you could see as a funny solution the "cork end seal" .
In that Soloporsche meeting someone told him about an existing kit called LN. He didn't know anything about them, in fact he says "LM" ... The hybrid bearing was an advise from his brother in-low (working in a industrial machine pieces store), and he was said that the ceramic ***** very superior to steel ones.

So at least this is a Very impressive anecdote for me.

ivangene

sounds like he got lucky !!

thats a case where "fixing" something could be worse than leaving it alone, very lucky indeed

juankimalo

Bruce, in Soloporsche (a small community compared to rennlist or other US forums) we have more than 50 documented engine failures.

http://soloporsche.com/showthread.php?t=20608

I tried to compile data and give a claim to Porsche Iberica (spanish import dealer). I opened a thread in which we asked for Porsche workers to explain their real experiences.


We received an extended explanation about this issue by a responsible of a Porsche Center, and how Porsche was procceeding. His final conclusion was that this engine has a real wrong design, but not only for the IMS, besides It's plenty of fragility. In Barcelone, tehre are to Porsche Authorized Dealers. One of them replaced at least, one engine per week, last year. Not everybody who enjoys a Porsche are so freak as we are here in the internet specific Porsche forums.

http://soloporsche.com/showthread.ph...t=trabajadores


The IMS is one of the most important problem in M96 family, but It's very well know here several years ago.
In soloporsche we count with a real expert who knows each detail of Zuffenhausen, and constantly in contact to Motorsport division 26 years ago. He always said that this engine was a complete designed disaster. But I'm not going to say the same things that were told for others here, because this is an old tale, well know for everybody who wanted search for information.
Nevertheless, I love my 996, and enjoy very much driving it, and hope to do it for a long time. I extreme the cares, the maintenance, the way of driving, the oil tipe, etc.

PelicanParts.com

One thing is certain, the cause of the bearing failures is unknown and unpredictable. That is why with the upcoming Pelican kit, we recommend replacing it every 30-40K miles. I believe that installing Charles' super-duper ceramic bearing will help tremendously to extend the life of the bearing/IMS assembly. But since no one fully understands the failure mechanism or the factors that influence it, repeated failures in the future are possible regardless of which type of bearing you use. This was somewhat accentuated by the fact that both the single and double row bearings fail in a similar manner under similar conditions (meaning that it's not an overloading condition on the bearing). It it my opinion that the best method to guard against failure is to replace the bearing often (30-40K miles).

-Wayne

BruceP

All due respect, Wayne, that's conjecture until someone comes up with a failed aftermarket bearing. I don't wish it on anybody (least of all me), but that's what it would take to convince me that this is a wear item.

Again, the simple logic is that they don't all fail. Thus, the design is feasible if the bearings are up to the job. It's axiomatic.

juankimalo

Hebmuller from Soloporsche, told us the same explanation as the Porsche Motorsport Division friend. It's very difficult to translate but I'll try.
He works in Porsche and as an expert engineer, have enough information to say those comments that we are not used to hear.
We must say that in Soloporsche, the 3 admins talked to him before alowing the registry. (we checked the real identity).


http://soloporsche.com/showpost.php?...1&postcount=48



Sorry for the translation, but It was not easy...



Good evening guys, and excuse that I’m not going to reveal my real name because I‘m working for Porsche Company

- Why are 996-997 and 986-987 engines failing?
First of all we must deny that 997/987 were failing the same as 996/986, but the truth is that they haven't enough km. done yet. Till they launched the second generation 997/987 Mk2 they didn't fit the problem. Unfortunately all you know the problem, and It’s the IMS bearing failure due to the internal steel ***** wear which make the bearing fail and cause a breakdown. They took the more simple decision: to delete it out of the engine design. Before this, they tried to reinforce the area but It was unsuccessful 'cause It was a wrong conception, a wrong design not a failure due to a bad quality of the materials employed.
There's a thing that we have to understand clearly.



Porsche was producing an exceptional engine (GT1 block based), and this was the one which built the indestructible Porsche reputation, but It was too much expensive to produce. Porsche was in a tricky economic period, and our loved Wendelin, saved the brand selling the Boxster, 996 , Cayenne for hundred of thounsands without any difficulty. They earned a lot of money in each product, which was very cheap to produce, nor those cars with the GT1 core.
They offered a boxer engine (6 opposed cylinders) whre the shaft works in a steel block, into 2 aluminum halfblocks. They sold it as a brilliant idea to save weight as It could use aluminum blocks (cheaper than steel) which didn't support the efforts directly, as the steel internal block was the one which was designed to received those efforts. Not very bad idea, but... both ultralight aluminun halfblocks (and too much cheaper than GT1) had to support IMS, shaft pulleys,... and what's more: besides the normal efforts they have to support, they add a new effort, don't forget that the crankshaft was installed in a 'false' steel block into both aluminun blocks. The expand coefficient of the different parts (aluminun and steel blocks) is not the same and sometimes the allignment is not perfect. It's something like if the crankshaft and the IMshaft, didn't work in parallels way. They are only a few thousandths of mm but working at these rpm, and with both light aluminum cast blocks, they finally produce a little imbalance into the bearing *****. GT1 core based engines, have no this problem because they are different and the are the most reliable engines in Porsche brand. Oddly they are the most powerful and sporty models, like GT2, GT3, GT3 RS, and TT, in both models 996 and 997. They are very strong and their owners like to track their cars and ask too much of them.

- Why Porsche didn't move any finger to solve it?
Excuse me but I have to say that part of the problem is in the Porsche enthusiastics, because they didn't make any decision. The same people who said that the 944 was an Audi transformed and not a real Porsche, because It wasn't a 911... they rised the 911 to the heaven instead of admit that It's a certain problematic car. But the proud of nine-eleveners is too high to pass through. Then if there's a fantastic product which never fails, why to change something which is a best seller? 11 years after the 1st M96 engine was produced, as a protective enviroment hard law, they decided to susbtitute M96/M97 engine by the new generation, and solve this deffect at the same time.

- Do Porsche think about their customers sattisfaction? The only aim of Porsche is to get care about the customers buying new vehicles. When a customer suffers an IMS bearing failure, and is the first owner, Porsche Centers don't use to deny a new engine replacement, including in the most times, to customers out of warranty. When you are the first owner, all the inspections made in you offcial dealer, and out of warranty, you could receive a special treatment if you claim hardly. When you go to the dealer being the second or third owner, we directly charge the whole engine budget. We don't care about these customers: that's Porsche policy.

- Will my 996 be a longlife car if I overcare the engine?
Some years ago, one of the most common reasons about engine failures was driving fast, hard driving, high revs... This was a bad excuse and in the whole life, a 996 engine is in a 60% range of efforts (a 300 HP car). Think that in a 'miserable' Renault Clio 1.1 lit. we are driving at high rev. almost the complete engine life because It has no enough power to go up a simple ramp. And a Renault Clio engine is almost eternal compared to a 'real Porsche'.
A IMS failure is caused in a random way , more than a high revs vehicle. I worked in lots opened engines, Tiptronics (not a hig revs pass through) with only 40.000 km, other manuals, 997, 996, well cared, bad cared , and it's fortuitous. It's just the same as playing to russian roulette, but instead of with a single bullet, with 3 bullets... because the frequency is too high.

- What can we users do?
You have to claim hardly, you have to compile data, you have to join efforts, to show it to the car magazines. You might condemn it


I'm a Porsche lover. I really love the brand but It's too hard for me writing things like these. I always am defending 924, 928 and the rest of models that 911ers don't like as a real Porsche.

Sorry for the brick (spanish expression for these long paragraphs)

smshirk

I can't believe no one has chimed in on this for 4 hours.