IMS Failure is not a Myth.

[pothole]

Originally Posted by feelyx

I had done some research on the life span of the bearing Porsche used. According to a "person" in a bearing company that supplied Porsche with the IMS bearings, the 6204 has a limited life span. The bearing was shipped out with 1 seal missing and no lube in the bearing, so who knows what was used as lube, and who, what, or where... they used to snap on the other seal. Also, 1 more tidbit there is a percentage of lube used to the speed limit of the bearing. Example.. if the bearing has a limiting speed of 10,000 rpm, and you are running it at 7,500 rpm, then you fill the bearing between 33% to 50%. If you are running the bearing at 2,500 rpm, then you fill the bearing 50% to 66%.

Porsche should of left the bearing filling, and seal installation to the bearing to the mfg. and this would probably be a non issue. This research was done on the double row bearing used to '99, and if the bearing, was filled correctly, and not damaged on intallation, or overrev'd etc. should of lasted into 100k's with no problems. OH, and as soon as I mentioned "Porsche" the "person" shut up and would not give me anymore info.

Heh. Interesting story.

Personally (and I have absolutely no proof of this), but my view is there's way too much smoke around the IMS issue for it to be a minor flaw affecting a small number cars. All engine designs have minor flaws affecting a small number of engine.

You often read of Porsche employees not being allowed to talk about it. If it was a minor issue, there wouldn't be any need for secrecy because the potential liability would be small. On the other hand, if it's a major issue, the motivation to maintain strict discipline over who says what is critical.

But for me the most telling thing is that even if it's as low a, says, two per cent that's still very high statistically and certainly high enough that you would have expected Porsche to have rapidly addressed and to all intents and purposes solved the flaw.

When the problems with Nikasil liners became apparent in BMW engines in Europe, they changed the liner material. They also changed out bad engines under good will for getting on for 10 years.

I also wonder about the wisdom of messing with bearings that have proven longevity. Mine's on nearly 100,000 miles. Honestly, if you offered me a free upgrade, I'd have to think about it before taking it (well, assuming the fitter wasn't willing to replace the whole engine should the new bearing fail).