RMS Question

[Brucelee]

Originally Posted by z12358

I would have escalated even after the SECOND rms issue was discovered only 3k miles after the first one. What happened to you is unacceptable. And I wouldn't even bother making claims on the aftermarket warranty. You are still experiencing the problem that started and was dealth with while still under Porsche warranty. Warranty fixes should also have a warranty on them, otherwise they're not fixes at all -- your case in point.
Z.

Dead on! What he said!

[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.

[MNBoxster]

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.

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

[porsche986spyder]

Originally Posted by MNBoxster

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 maching, 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

Thanks for making more sense out of what I was trying to say. So is it true that the newer models have fixed this problem? I heard that it is no longer an issue with the 987 models.

[MNBoxster]

Originally Posted by porsche986spyder

Thanks for making more sense out of what I was trying to say. So is it true that the newer models have fixed this problem? I heard that it is no longer an issue with the 987 models.

Hi,

Nope - all 987's are susceptible. There is some talk that it's less frequent, but I don't believe it. The Seal is on it's 3rd or 4th Gen, and this has staved it off until later mileages are racked up it seems, but I think it's too early to say that the 987 won't experience this problem at the same rate as the 986.

They're all variants of the same basic engine design - M96/20 (2.5L), M96/21, 24 (3.2L), M96/22,23 (2.7L), M96/25 (2.7L 987), M96/26 (3.2L 987)...

Happy Motoring!... Jim'99

[JackG]

Originally Posted by MNBoxster

Hi,

Nope - all 987's are susceptible. There is some talk that it's less frequent, but I don't believe it. The Seal is on it's 3rd or 4th Gen, and this has staved it off until later mileages are racked up it seems, but I think it's too early to say that the 987 won't experience this problem at the same rate as the 986.

They're all varaiants of the same basic engine design - M96/20 (2.5L), M96/21, 24 (3.2L), M96/22,23 (2.7L), M96/25 (2.7L 987), M96/26 (3.2L 987)...

Happy Motoring!... Jim'99

Has anyone ever cracked open the early and later variants to see if there have been any changes made to the casting?

It's not out of the realm of possibility that the crank support bosses, seal mating area, etc.. have had running changes made to help prevent or eliminate the problem. They would still be classified as M96's, that's why they call them variants.

[Brucelee]

I have to support what Jim says about the 987. My local service guy has been replacing them since day 1.

The new seal has been borrowed from the Cayenne as I understand it.

What's up with that?

:dance: