Quote:
Originally Posted by porsche986spyder
I have to agree with what these guys are saying, if some one replaced your RMS with a new one, they should have some type of garuntee on the work that was done.
On another note, my machanic that replaced mine said that the Porsche uses a CASTING process that is done my a machine that leaves the SURFACE with a ROUGH finish. That is the real cause of the problem. If you have ever seen a casted alluminum block up close, you can see what I am talking about. This is why the seal DOES NOT work properly. In many cases my mechanic would recomend RE-SURFACING, the area where the seals are made to create a BETTER seal between the parts. Porsche is well aware of this because most of the newer models like the 987 from 2005 and up use a newer process that does not leave a rough surface which so far has cured the problem. That's just my 2 cents. 
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Hi,
Only partly true. The newer models do not have a different block. Porsche, to save money on Production Costs, adopted a Casting technique invented by Audi which eliminated the need for post-cast machining,
there is no traditional center-bore machining at all. This results in a % of Blocks where the opening for the Crank is not properly centered. This is one cause of RMS - the Seal can never be properly seated to begin with.
The other involves the way the Crank is cradled. This design allows the Crank to meander slightly off it's centerline, and this is what abrades the Seal leading to premature failure.
All variants of the M96 engine suffer this and to a high extent. At least 25% from anecdotal sources and if you believe Scott Slausen at PCA Tech Committe, he states that
all M96 engines will have this problem. ..
Happy Motoring!... Jim'99