Pre Purchase inspection of a 996 looking for RMS

Hi all, If RMS is a concern when buy a 996 why not take the car to the dealer to be tested with their special tool? Assuming that you are interested in a used 996 with some miles, that does not have a history of RMS but it is close to the end of its warranty. If you are serious about buying the car why don�t pay the dealer to check it and give you the tolerance with their tool? Then you know that if you develop an RMS at sometime out of the warranty you will only go in for a seal replacement and not for an engine replacement (assuming that the tolerance of your engine doesn�t change with time or is it)? Thanks The Analyst

To check the tolerances with the Porsche tool the following would be done.... drop the transmission out removing clutch, pressure plate and flywheel and then remove the RMS (destroying it during removal), check tolerances, insert new seal reassemble. In other words the same procedure for replacing a rear main seal. Cost approximately $600-$1200 depending on who you talk to. Very expensive PPI. Additionally, just because the engine is within the "tolerances" does not mean you will not have a RMS leak and there is no guarantee that it can't be out of spec. in the future. The true cause of the problem is still not completely understood or know (at least by those in the public as someone inside Porsche probably knows).

Some may consider that to be a very expensive PPI. The parts are cheap, but the labor is going to run about $600-$800.

OK this is going to be an expensive PPI but�we are about to drop 50K on a car. Instead of spending 800$ I would think of it as saving 49K. I�m assuming that the engine will NOT get out of specs in the following years. According to Brian the cause of non concentricity is not known and an engine that is within the specs now could be out of specs in a few years� Do we have a record of anyone that had an engine with RMS (that was in specs) and after the seal replacement needed an engine replacement due to his engine been out of specs (with time and usage). This is just an idea�I would hate to spend 50K and then another 10K for an engine in 2 years!!! I would rather stick to my 17 year old 944 (daily driver!!!) that is still strong and without any oil drops. Thanks, The Analyst

This is just a guess.....but I can't believe that Porsche installs engines in cars that are out of spec. So the engine must go out of spec at some point during usage. How and why, I think only Porsche knows and they're not talking.

I am not a technical expert on this subject by any means. I suggest doing a search here and on Renntech.org on the RMS issue. There are some great technical discussions with regard to the problem and possible causes and solutions. While the nonconcentricity of the engine case is definitely a problem, my point is to say you can have an engine casing that passes the concentricity test yet till continues to have RMS leaks. I don't know of if passing the concentricity test means the casing will never be out of spec. The biggest problem with the RMS issue is the lack of solid evidence of the cause, the fix and the long term results.

You would be wasting your money. You could pay for the gearbox removal and it may show that the RMS is fine. PPI ok. Next day the RMS could fail. The problem is that the RMS could fail at any time on any year 996 C2/C4 or Boxster. The only thing you could do is to look under the engine and see if you see it leaking. If it is then walk away. If it ain't then it may be just a matter of time. Then again it may never fail. You take your chances. The best bet and only good move is to ensure the RMS is covered under warranty.

If the search function works then search under my user name. A local Boxster owner I have known for years had 4 seal replacements. The last 2 with all the special tools. It still leaked and the engine was replaced last week.

For what it's worth, last week after I got my '02 cab back from its 45k mi. service, the dealer told me I had an RMS problem--the second one. The first was at the 15k mi. service. He also told me that PCNA told him not to use the special tool to measure concentricity any more and just to make the manual measurement. I'll know this weekend whether I'll be getting a new engine.

I also have heard from my local Porsche Tech that PCNA has instructed them not to use the measuring tool any more and to measure it manually. Just to further confuse the discussion is that there are actually 2 seals that tend to leak on the back of the motor. One is the RMS, and the other is the intermediate shaft seal. Both will seep oil into the bellhousing and onto the floor. Fortunately, the way the seals leak (a more accurate description would be weeping) There is very little if any chance that the clutch, flywheel, or pressure plate will become oil damaged. In fact other than a messy annoyance, it does not do any damage at all. This is not like the cam chain tensioner problems of the old 911s or the valve guide problems of the 993s.

WHEN I WAS EMPLOYED AT A PORSCHE DEALER WE GOT IN THE NEW TOOL TO MEASURE THE RMS TOLERANCES.WE CHECKED THE TOOL AND FOUND IT TO BE OUT OF TOLERANCE SO WE DIDN'T USE IT AND DID THE MEASUREMENT MANUALLY WITH A SNAP GAUGE AND A MICROMETER.

When I bought my 996 I had it taken to IRA Porsche for the inspection. Checking for oil leaks of any kind was part of the routine. It was very thorough including break pad thicknesses, tire tread remaining, all functions tested, etc. and only cost $100. I even got to discuss things in detail with the mechanic who performed the inspection over the phone. I made this a condition of the sale and the car passed with flying colors. I imagine that the same inspection could be done at any dealer. I agree with Scouser that spending the $800 or whatever on the RMS/tool test would be a big waste. Who knows, the car may be one that will never develop a leak and installing the new RMS partially incorrectly could actually create one. How does that saying go? If it aint broke...