RMS Question, - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Hello new friends~!! I am a Boxster S owner in South Korea and I love the car. I believe the RMS problem is quite common with 986s and 996s. My car has run 32000 miles on clock. I had a porsche mechanic to have a look at it when changing the plugs but he told me that there is a minor leak and it is quite common with all porsches ( lol ) and it's nothing to worry about, because the leak is minor. I have checked it again when I had my tires changed this afternoon and there seems to be a definite leak. I kept checking the floor of my garage for a while but it does not seem to drip on the floor. What should I do? I intend to own this beauty for a long time. But the warranty has expired and I am quite worried about the cost of repairing. I did a search on couple of websites but most people say that even RMS is replaced the leak will start again at some point, then what would be the point of replacing it? Would it be okay to leave it for a while? or is it something more serious that I have to get it fixed immediately? Thanks,

You can leave it for how every long you want, it just depends on how much oil you want to drip. If it isn't hitting the ground yet, then you probably have a little time, but it will only get worse and will need replacement. If it starts leaking bad enough, you can ruin the clutch, though that is an extreme. It is about a 10-11 hour job total, with cost of parts about 12 bucks. Actually while you are in there, you need to do a clutch and have the flywheel turned as well. No point of putting those used parts back in, then having to go change them out again in a few years. The stock boxster clutch is only a few hundred dollars. Here is a journal of the RMS seal i did a few weeks ago to let you know what is involved. http://www.turbo911.com/showthread.php?t=220 Oh, and not all porsches leak oil at the RMS seal like you mechanic says. It is an issue with the boxster and 996. There is a chance that when you replace it, it will leak again. The new TSB with the updated bolts and updated tool for installing the seal helps to prevent that. The tool to seat the RMS has changed, and will now set the seal to a certain depth, which was different that previously.l

Hi, A couple of points: The Flywheel used in the Boxster is a Dual Mass Flywheel and Porsche does not recommend that it be machined or refaced, rather, that it be replaced. Add to this that the Flywheel on the M96 Engine contains the Vibration Damping usually done by the Pressure Plate (no springs on the M96 Pressure Plate - they're on the Flywheel instead). Machining or Refacing will seriously weaken it and it could shatter at high RPM, creating all sorts of issues. Also, during initial Factory assembly, the Rear Main Seal (RMS) is seated to a depth of 11mm. When replacing the RMS, the new seal should be seated to a greater depth of 13mm so that the sealing lip is seated on a clean part of the Crankshaft because the previous seal will have left a wear mark on the Crank making it difficult for the new Seal to properly seal. Your RMS makes contact with the spinning Crankshaft and as such is a Sacrificial Seal - EVERY RMS will eventually wear out and will leak . Unless your leak was caused by an Out-of-Round Crank or Out-of-Tolerance Center Bore in the Block, which will greatly accelerate it's Wear Rate, you can replace it fully confident that it will last for it's designed lifespan. If yours is currently leaking, you are on borrowed time. Some leaky seals will go many XXXXmi. before they become catastrophic, others will not - no way to tell which will and which will not. If you let it get to this stage, SERIOUS Engine and Clutch damage Can occur in just a few minutes running time - remember, it's the RMS which contains the Oil in the Motor! I don't want to scare you, just give you a clearer picture. If it were me, I'd consider having it done at the nearest opportunity combined with other work such as a clutch to better ammortize the Labor Costs. Also, do some research, many Dealers and Owners have had good luck replacing the Stock Boxster Part with the RMS from the Cayenne which apprently has more give to it and so better seals those engines which are Out-of-Tolerance. Hope this helps... Happy Motoring!... Jim'99

Thank you very much for your help PorscheDoc, Just one more thing, mine is tiptronic so what difference are there to manual mission clutch and flywheel etc. Thank you so much.

Hi, I see this is for Doc, but I'll reply anyway . The Tiptronic equipped Cars suffer fewer RMS Failures because the Torque Convertor (essentially a Viscous Coupling) reduces the amount of stress placed on the Flywheel/Crankshaft - there's less movement around it's designed Center-of-Rotation resulting in less wear to the Seal. Hope this helps... Happy Motoring!... Jim'99

Thank you MNBoxster I haven't seen your post when I was replying.. It was a great help. I will get the mechanic to check the leak again, really hope it's not from RMS. And I hope labour isn't so expensive..spent too much recently having tires changed etc etc Motor on~~!!

Aquido, you did not write about WHERE the leak was coming from. Boxsters and 996's are notorious for cam cover leaks, which aren't catastrophic. I have one in fact that bugs me, but my mechanic tells me not to worry about because many of them do this. It's not common for it to mess up the whole engine like the RMS leaking will do. BTW, some Boxsters are being fitted with the Cayenne's RMS (it fits) as it's more sturdy and is said to last a lot longer. Installation is harder from what I've read though. Don't take my word for it on this one... It's a result of some online reading I've been doing and I am not sure of its real-world truth.

The leak is from centre. Some sort of linking part behind the place where oil plug and oil filtre. I will be off to Ecuador soon for a month, so I will try to fix it when I come back. Thanks

How much would a dealer charge to have an RMS changed here in the US? TIA!