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Old 04-26-2011, 02:07 PM   #1
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Ims, Rms ??

I've been reading a couple of thread and saw the IMS and RMS abreviation, talking about old bad design, should replace before trouble etc etc. But I have yet been able to know what is IMS or RMS. Anyone can explain? I own my 2000 Boxster S for only a mounth, still learning.

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Old 04-26-2011, 02:38 PM   #2
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You and I both!!
Back in 2004 I had a '00 S with no problems. 1 year later I traded the car with no issues, but worried about this "RMS" issue.
(7 years later) I now recently aquired an '01 S with 85k miles with no service history and just courios to know how to go about checking on it to see if it's gotta be done or has been done. Engine runs fine, no oil drop'ns. Porsche dealer in my area is useless.
However YOUTUBE has been helpful with there videos, but there's nothing like experience personel here.
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Old 04-26-2011, 03:29 PM   #3
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Let me start by saying “Search is your friend……….” There are lots of information on both the IMS and RMS issues.

RMS, or rear main seal, is the oil seal on the rear of the engine’s crankshaft. The M96/97 engines had problems early on with seals that would suddenly spring significant leaks. Porsche at one time was covering the RMS under warranty, even for cars that were slightly out of their actual warranty period. Porsche came up with a revised seal that has completely eliminated this problem. Any year engine can be updated to this seal, which costs about $20, only problem is you need to pull the gearbox, clutch and flywheel to get at it. In general, the cars that were going to have the big-time RMS problem already have for the most part; so it has lapsed into a kind of non-issue. If you are going to have the clutch done, get the new RMS at the same time.

The IMS, or more precisely, the rear intermediate shaft bearing on M96/97’s can fail with catastrophic consequences. Typically, when this bearing lets go, it takes the engine with it. LN Engineering developed a replacement unit and method that allows the OEM bearing to be removed and replaced with a redesigned unit during a clutch change which has been very successful (more than two thousand installed no failures to date.) LN and FlatSix Innovations have excellent websites with tons of information on the subject.

Anything really new is invented only in one’s youth. Later, one becomes more experienced, more famous – and more stupid.” - Albert Einstein
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Old 04-26-2011, 03:37 PM   #4
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RMS = rear main seal. seal between the transmission and engine. starts to drip (some say sweat is a better description) oil - usually a few drops noticed on the garage floor. not that big of a deal as long as you keep an eye on the oil level and don't let it get low. some cars go years before it is ever fixed. requires dropping the transmission fix. a lot of people have it done when a clutch is replaced, since they require a lot of the same labor. the part itself (a gasket) is cheap, but the labor is expensive.

IMS = intermediate shaft. though the problem usually refers to the bearing that sits at the end of the shaft where the engine and transmission meet. the bearing seal wears out over time even though it was intended to be sealed for life. when that happens motor oil gets into the bearing and washes away the remaining grease. since the oil does not lubricate the bearings properly they begin to wear and the shaft is no longer stable. the timing system relies on the shaft/bearing and eventually things go south. i've heard it described thusly - the pistons and valves clap hands and the engine "self destructs." gruesome sounding. in actuallity it doesn't blow up or explode, but usually knocks a hole in the engine - the engine is scrap metal by then at any point. again requires the transmission and engine be seperated (it's even in the same general area as the RMS). some people noted a "rocks in tincan" sound before a failure while some receive no warning - simply a bang and the engine quits.

RMS can be done at the dealer - though expect to pay a lot of $$$. porsche does not/has not acknowledged the prevelance of the IMS flaw. there is dispute among many as to the actual rate of failure, but that's usually irrelevant to those who experience it.

LN Engineering (working with Jake Raby) have come up with a more robust IMS bearing that they say all but eliminates the failure. again the cost of the part is negligible (~$600) depending on model, etc. but labor is expensive. more and more indy shops are starting to offer the service, but it takes some experience and knowledge since the bearing was not intended by Porsche to be extracted. newer models must have the case opened since the bearing can not be extracted.

most agree that not treating the car like a porcelin doll is a way to stave off failure - drive it well and shorten the recommended oil change interval.

some people feel the "problem" is hyped out of proportion - or even deny it is a problem at all. in the end, do some research, talk to others and make your own decision.
"Speed has never killed anyone, suddenly becoming stationary... that's what gets you."
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Old 04-26-2011, 03:50 PM   #5
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Originally Posted by tonycarreon
some people feel the "problem" is hyped out of proportion - or even deny it is a problem at all. in the end, do some research, talk to others and make your own decision.
IMHO definitely a real problem but definitely hyped out of proportion.
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