wildbilly32

More educational tidbits:

JTT

Great! Thanks for taking the time to do these Jake. There will always be naysayers, and critics, but the silent majority greatly appreciate your efforts and willingness to share knowledge.

Porschetech3

Thanks for the video Rev. Raby, I had forgotten about the Porsche factory repair of the M96/20 engines back in 99. I was recently asked if Porsche ever put any steel sleeves in m96 engines and I replied no, but I had forgotten about when there was a fire at the engine plant in 99, the engine case casting machines were moved to another site and reset-up. There was a problem with core shift on the newly set-up machines that put production behind, and Porsche repaired the blocks by installing steel sleeves in some cylinders and sometimes all 6 cylinders.But there was a mistake in the machining of the radius at the "top hat" of the interface between the sleeve and the case that resulted in a crack of the sleeve "top hat" when pressed into place. After a few thousand miles (less than 30k) the "top hat" would beak off or the sleeve slip down and hit the crank, locking the engine. As far as I know this is only an issue with M96/20 2.5 Boxster engines, and was not an issue with the M96/01 or any other 3.4 engines of 1999..Most of these engine have been replaced by Porsche under warranty, but if you find a 99 986 "cream puff" with low miles, mite want to be aware of this..

Flat6 Innovations

The repair sleeves were a metal matrix composite. Not steel, they break in half really easy.

Porschetech3

Since "steel" IS a metal composite, I think the Porsche engineer/instructor, who advised us on this, used the term steel due to the metal matrix composite base metal is iron, same as it is in steel. Without having a name for the specific metal matrix composite , he used the well understood term steel.

wildbilly32

So let me get this straight. Porsche moved their casting machinery and in the new location the machines produced blocks with a fatal flaw. Because this fatal flaw put them behind production goals they installed a metal sleeve that also had a fatal flaw! Right? That is the true definition of not following established quality manufacturing processes and being driven solely by production requirements. Unfortunately, I saw examples of this from manufacturers my entire career. Glad I didn't have one of those cars. One question: did Porsche fix the defective/soon to fail cars they produced? If they did my guess is it was much more expensive in so many ways than not meeting the original production goals would have been in the first place.

Flat6 Innovations

He’d probably never assembled an engine personally..
Lets just says those sleeves aren’t ferrous.

Flat6 Innovations

Jim Pasha (RIP) wrote the full story on this occurrence in the December 2008 issue of Excellence Magazine. Ironically that’s when my engine program was first featured for these engines.

Basically, new cars were sold with “repaired engines”