I was a Mercedes SLK owner for about 10 years and spent a lot of time on that forum. I mentioned in the forum that I had traded in my SLK for a 2009 Cayman. The SLK forum moderator invited me to post some pictures which I did (along with some positive comments). The Cayman apparently has a good reputation on that forum, but I would be interested in what you think of the following comment:
"The Cayman is indeed a fine--even world-class--automobile. Over the years I have owned several (older) Porsches, and each was an improvement over the last. Reluctantly, however, I chose my SLK over a similar-year Boxster. Why? Because of Porsche's failure to correct the infamous rear main seal and Intermediate Shaft problems that result in the failure of too many engines (think $$$$), and its reluctance to stand behind engine failures due to these known design flaws after the engine was out of warranty."
"All this from a company that proclaims it's engineering excellence? Check Porsche Pete's Boxster Board for more on this. After 10 years of producing flawed engines it MAY have corrected the problems with the recently redesigned flat six engines. I hope your Cayman has the new engine. Compared to a massive engine failure (estimated to be as many as 20% now, with some saying it is more a question of when, not if), some interior paint-peeling ranks WAY down the problem list. And I'm surprised by how much I like my 230. In fact, I should have purchased a 32--and I'm lookng!"
Were these problems fixed in the DFI engines or earlier? I just bought a new 2008 Cayman S Sport--should I be concerned?
The problems were lessened to a great degree around 2004-2005 time frame, only a very few cars have had the problem since, prior to that, yes the problem was more widespread. It is my understanding that there were a number of fixes for the seal that were tried and finally a workable solution was arrived at and implemented and the occurrences fell off dramatically. The DFI engines are a completely different design and don't suffer from the same problem.
As mentioned that was an issue early on regarding the engine seals. I had a SLK and did not like it at all. The seats were uncomfortable and bottomed out over bumps, I had a transmission leak at 2000 miles, The car creaked all the time, the steering was numb feeling, the auto/ manual sport transmission was extremely slow to shift and the shifts were side to side instead of the normal up and down movement. I can go on but you get the idea. Mine was a 2005. After test driving a Porsche (a 05 Boxster at that time) it was clear there was no going back to SLK's.
I'm getting kind of annoyed that several magazines, and occasionally some posters here, refer to all new 2009 Porsche engines as DFI (including those in the Boxter/Cayman).
As we know, only the Boxter/Cayman S has DFI. The 2.9 engine, though new, is NOT DFI, while the 3.4 engine is....
(The 997's now all have DFI)
It is my understanding that the 2.9 is indeed the new engine design without the Direct Injection. Given the newness of the Direct Injection engines, the 2.9 may prove to be the more dependable engine. That is said because the direct injection engines are new and there are not that many miles on most of them. We do not know how the direct injection engine and its injection parts will hold up. There have been some grumblings about the 997 with direct injection causing carbon or engine fouling however, I can't get a handle on that issue to ascertain if it is something to be concerned about. Porsche has not always been forthcoming about owning up to the flaws in their designs as was the case of the RMS and Immediate shaft issues. All the old designs are suspect but got better after 2005. Still, it is a problem with the older designs even after 2005. Porsche did little fixes to try to fix the problem however, the only solution to completely cure the problem was to change the design to the newer 2.9 and 3.4 direct injection. Time will tell if the new engines are as trouble free as we would like.
It may be too early to know of any problems with the new engine block of the 2.9 and 3.4
However, one of the reasons I chose the 2.9 is because it didn't have DFI. Although the DFI is great, my car is my daily driver, and I don't track it, so it has enough power for me. Also, I hope to be able to put 100-150K miles on my car within the next 4-5 years, and I'm thinking that the non-DFI engine may have less long-term durability issues (carbon or sludge bulid-up, HPFP replacements, etc.), but who knows.
The new 9A1 motor is a completely new design, and is used in the Gen 2 987s, 997s and the new Gen 2 997 turbo.The GT2 and GT3 still use the previously used old-style split-case air-cooled motors with water-cooled heads, often referred to as the GT-1 motor. No doubt, with the debut of the new turbo using the 9A1 block, these cars will use it in the future, as well. The 9A1 motor does not have any of the problems mentioned here. That's not to say it may develop its own problems. This block is also used on the non-S Gen 2 987 Boxsters and Caymans, but with port injection rather than the DFI used in the other cars.
There were actually three different leaks that the M96 in the 996 and 986 cars, and M97 motors in the Gen 1 997/987 cars that were often lumped into what were called "RMS" leaks. These were the RMS (rear main seal), the bearing covers, and the rear case bolts. The real RMS leaks were mostly the fault of the block design in the M96 and M97 blocks where the crankshaft sat in a separate cradle that was then set into the crankcase. If the casting was not absolutely perfect on the case, the crankshaft could be very slightly off-center - when this happened it basically chewed-up the RMS, and there was a leak. For cars that were in-warranty, dealers were given what was referred to as a "go-no go" tool that was inserted onto the crankshaft to measure its straightness. If the tool didn't fit, then a new motor was installed. If it fit, then the seal was replaced. Over a few years, these seals were updated, with the last one being made of Teflon and derived from a seal use in the Cayenne motors. A combination of better casting and the OEM use of the new seals in the 987 cars made this leak rare in these cars. Again the new, 9A1 motors do not use this "cradle" design.
The intermediate shafts are a different problem - I quote Bruce Anderson from the November Excellence from his "market Update" on mid-engined Porsches:
"The M96 intermediate shafts are another problem area. The original Intermediate Shaft used a double-row ball bearing on the flywheel end with a single-O-ring bearing cover seal. In 2002, that was changed to a single-row ball bearing with a tri-seal in an attempt to prevent leaking. Both the double- and single-row bearings had a stamped steel cage and the cages can fatigue and break, letting the ball bearings fall out and cause destruction associated with intermediate shaft failures. Porsche moved to solve the problem in mid-2006, when it phased in a new shaft design which seems to have solved the problem. There are several after-market fixes that seem to work for the problematic early intermediate shaft problems.
My '06 CS was built at the end of january 2006 and it has been checked and has the new IMS design, so I would say most '06 and all '07-'08 cars have the new design.
Very nice update, Brad. Thanks for informing those fortunate ones of us who don't have the problem, but who hear all the complaints about the RMS.
You're welcome - Despite the continuing brouhaha, having a real RMS leak is not the end of the world. My 1999 996 had it at around 12k miles, and it was fixed properly. The people who have the car now (second owners) have had the car since 2002, it has about 55k miles on it and is still leak free. Some haven't been as fortunate, having to have them fixed more than once, but others were the recipients of brand-new, updated motors in their cars. The incidence of RMS problems in 987 M97 motors is really quite rare.