997 style IMS

So GNR996 and I both had reman engines installed around 2005/2006. We're wondering what the chances are that our remans were built with the new style IMS. If so, then this changes our plans for IMS upgrades when the clutches are done. So the questions are: 1) Can anyone post photos of the 997 style IMS area, ideally without the flange installed, but if the flange is different, then a photo that would be interesting also. Maybe a handy comparison shot of the 996 style IMS setup too? 2) Assuming that the new style case is a different casting than the old style case, is it possible to identify which case is installed looking from the outside in...ie without trans or engine removal). 3) Barring any distinguishing features on the outside...is there a engine number cutoff or anything. Hey thanks..

The cost of adding a LN Eng retrofit as part of a clutch/RMS job should be relatively small. Why wouldn't you do it? ...j

I'm in the same group. My reman engine was installed in Sept/October of 2006. All of the parts around the engine have the built date of May of 2006. Based on the built date and looking at LN Engineering's site & Flat 6 Innovations' info, mine has the 997-type bearing. There is no upgrade for these bearings. Check LN's site and check all of your engine's component built dates. You should get a good estimate of when your reman engine was assembled.

Quotes source post: 8638147

The later style can not be updated. The exact reason not entirely clear, but assume it is because the IMS bearing can not be extracted without splitting the case. Question 1 hopes to find out *exactly* why.

Starting to think we need an IMS sub-forum

Very good thread and it's the first actually in regard to this specific situation. I as well have a reman engine which was installed late 2005. And this has always been a grey area for me. I PM''d Jake and I never got a reply back a while ago (Even after typing every little detail off the invoice into the PM box) lol

Quotes source post: 8638531

and a oil forum at our peril we started a IMS thread... may as well be a oil thread. inquiring minds do want to know though.

An IMS subforum sounds like a great idea.

man, that is one seriously well discussed topic (no offense jasper, its just that there are 3 new IMS threads a day this week) if you have a "new" (aka big bearing) you can still have an "old" (aka ims kaboom) issue the bearing is HUGE by comparison but still a sealed unit and still has the exact same amount of "probability" that it could go bad the standard rule of thinking is the open the IMS seal (behind flywheel) and with a needle nose pliars butt the seal ring off the bearing and out thru the hole thus allowing engine oil to lubricate the bearing. This is not idea but better than no lubrication at all. - and if you get there and see that your motor has the standard (aka small) bearing you can just replace it. so - if it were me: I would wait till i had some reason to go in there or has some time and spare change to do a check/fix/replacement The probability that it will last till then is high, the results of waiting too long is well documented. (same ole crap shoot) other things to do.....get Jakes new IMS detector thingy....? Now my theory on the bigger bearing. IMO (please keep in mind this is an opinion based on some experience but not tested in any sort of lab enviornment or other, just a theory) the reason IMS bearings loose their grease has to do with the fact the the IMS shaft is seealed on all sides and full of air. During heating and cooling the air expands. The air escapes thru the only path out (the bearing seal) and with it pushes some of the grease out. When the air cools it creates a vacuum inside the IMS tube and such whatever it can back in (be it air or oil) the oil that gets sucked in becomes trapped because during expansiion the air goes out before the oil (less resistance thru the bearing seal) The oil that remains in the shaft gets repeated heat cycles and basicly cooks itself to death becoming less effective at lubricating and more of a corrosive/costic oil, during the process the hot oil emits what ever contaminants it can and those are passing thru the seal with the air too. Bad oil in, less air in, hot burnt oil, each pass = less grease in the IMS bearing and more of the contaminated oil. - there are then 2 modes of failure: one the bearing runs dry of grease tand the ***** pit, become etched, weak, wear more and eventually create enough heat to become a real problem, the bearing eats the ring (holds the ***** in place) all the ***** fall to one side and the 2 halfs of the bearing (inner and outter race) separate and all hell breaks loose - 2. the oil inside the shaft creates hydrolic pressure from expansion and the pressure pushes the bearing out of the shaft. as it gets pushed out with hydrolic pressure (remember this can be some huge forces..huge) the bearing suffers from the center pushing on the edges (designed to ride in the "groove") and the edges flake off causeing fragments to fall into the groove and create ball deformation, damage and eventual failure. - pretty imaginative? I have detailed photos so back to the larger bearing, they do not seal the IMS shaft the way the smaller ones do so why whould they fail? Shoot man, I'm gonna need some stronger stuff to take a stab at that one - but I would like to hear ideas. any I have my flame suit on so anyone wanna take pops at my theory, go right ahead. BTW... good morning and lets have an IMS FREE DAY one of these days

Quotes source post: 8638709

How great would that be

I don't get why they Porsche would make a newer revised IMS and it still be faulty? Or is it faulty?, I personally have never heard of a KABOOM reman engine? So did they F*%# up twice?.... if so, that's retarded.

awe twice? 3 times keep in mind - double row, then single row, than ginormous - and yes - I have seen them suffer

I'm all for an IMS-specific forum purely as a public mental health service. IMS threads on a Porsche Discussion Board are like Obesity threads on a Cinnabon Lovers Chat Board. You know its a major related issue -- but you'd rather not hear about it all the time. Takes away some of the joy.

thanks Ed. seems like a well thought out mode of failure. the point of the thread however was to help us identify what bearing a motor has... my motor was replaced in April of 2007 so I am guessing it has the updated parts as is Jasper with his.

This IMS thread reminds me of AAA. We hope, we pray, and we dread recidivism. I've spoken with Pastor jake, and I have heard of the evils of IMS hell, that befall the wicked and the weak. I'm going tracking with my 10K mile '05 C4S. Hoping for a trauma free ride.

you wont know till you pull the cover - when you do... you know what to do (remove seal - replace bearing) there isnt any other way to know for sure (that I have heard)

Quotes source post: 8638835

Thank you Ed Zacharry I'm not trying to start trouble or cover a topic that has been beat to death already. This particular subject has been discussed very little in fact. The point of the post was to tease out any *technical* information that might allow us to identify if an engine has the new style bearing. The reason for wanting to know is not the point of the post. You have to admit that unless you're "motor as a black box" kind of guy, it is an interesting thing to know one way or another.

All you need to do is get the engine serial number on the block to get a pretty good idea of what bearing you are dealing with. The bearing in the later reman engines is just larger in diameter than the case "hole". It requires the engine case to be split. Big money then. If you are doing the clutch,just take a look.

Quotes source post: 8638709

I'd say you're on the right track but your train is way too long and derailed itself somewhere in the first third of your hypothesis. From my observation, the bearing seals are not up to the task of being splashed and soaked with very hot oil, and that is what eventually leads to the breakdown and subsequent washing-out of the grease. From there you're left with a bearing with internal clearances designed for thick grease but now lubricated only with an inadequate film of oil...and mostly dirty, abrasive, corrosive, old, trapped oil at that. Removing the seal off an OEM bearing does allow lubrication from oil splashed by the cam chain, but that is consequential, and not an engineered means of lubrication (opposed to eg the way in which the crankshaft bearings are oil-lubed). If I had an engine with the larger bearing I would only remove the seal if I saw that it was breached, because a little lubrication is obviously better than none. But I would not consider it a fix, nor would I rest easy. The LN bearing is not merely un-sealed, it is constructed specifically of a design and materials to better hold up under the less-than-ideal lubrication environment posed by the location of the bearing.