Shavings from old failed IMS (??) now showing up?
10-11-2016, 12:19 AM
#226
Drifting
I suggest a few other influences
1. There was already a competing DOF kit for a deep groove ball bearing IMSB
2. The Solution had an oil feed (yes,I know it is different!)
3. There was little field testing of the roller prior to sale so this was an 'insurance' against the risk of the roller overheating and an answer to the endless "is it load or lubrication?" question.
4. It cost very little(one punch!) and it was easier than the DOF kit in 1. above.
5.The 'splash' isn't quite like that but although it may have been adequate for a ball IMSB, there was no field data to proove it was adequate for a roller.
Feel free to add more !
The end result has been indisputably good and I concede better than I expected (but ONLY after they added thrust control to the earlier design-after howls of protest about the original poor design.)
Who knows how good it could be if they added Pedro's DOF to a roller IMSB ?? BTW you can do this(in theory) with some of the DOF kits because you can order them without a bearing and then source your own roller bearing(part # NUP204?). I am not advocating that -just for debate !
1. There was already a competing DOF kit for a deep groove ball bearing IMSB
2. The Solution had an oil feed (yes,I know it is different!)
3. There was little field testing of the roller prior to sale so this was an 'insurance' against the risk of the roller overheating and an answer to the endless "is it load or lubrication?" question.
4. It cost very little(one punch!) and it was easier than the DOF kit in 1. above.
5.The 'splash' isn't quite like that but although it may have been adequate for a ball IMSB, there was no field data to proove it was adequate for a roller.
Feel free to add more !
The end result has been indisputably good and I concede better than I expected (but ONLY after they added thrust control to the earlier design-after howls of protest about the original poor design.)
Who knows how good it could be if they added Pedro's DOF to a roller IMSB ?? BTW you can do this(in theory) with some of the DOF kits because you can order them without a bearing and then source your own roller bearing(part # NUP204?). I am not advocating that -just for debate !
Last edited by Schnell Gelb; 11-14-2018 at 11:47 AM.
10-14-2016, 08:12 PM
#227
Drifting
Curious. I have a boxster that had ims bearing replaced at around 60k with LN engineering bearing. It now has 112k. Should bearing be done again? If so, roller bearing a better option?
10-14-2016, 08:19 PM
#228
Drifting
According to the LN site the answer is "Yes" and it is about time to check the clutch friction plate and DMF anyway Assuming manual g/b). If it is a Tip - I'll let others advize.
Whatever, get a "while you are in there" list going so you are ready .
Whatever, get a "while you are in there" list going so you are ready .
10-14-2016, 09:26 PM
#229
Race Car
IMS retrofit is supposed to be good for 5 years or 75k miles.
11-14-2018, 03:58 AM
#233
Advanced
Sorry to revive an old thread, an interesting story with a happy ending for the OP but nevertheless a debatable ‘cause’.
Key points:
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone. However, we don’t really know, because there was no independent inspection of the LNE bearing. We have to take Raby’s word for it.
Why would I suggest a different cause to the one put forward in this thread? Because LNE bearings do suddenly fail due to manufacturing defects. My own Boxster S had such a bearing, and with exactly the same debris symptoms as the OP. On removal of the LNE bearing, I found one of the 18 ceramic ***** (it was a double row bearing) to be badly pitted with surface cracks. This one faulty ball was steadily eroding the steel bearing races, and was the sole cause of all debris. I replaced the IMSB with a standard SKF all-steel double row bearing at a fraction of the cost of a hybrid one. 6,000 miles later, no debris in the (standard) filter, on the magnetic sump plug, or in the sump…
Thought it worthwhile opening this thread again, given someone with the same symptoms might find the thread and not look to at least one obvious cause.
Key points:
- The OP’s car had a failing IMSB with metal particles in the oil before he bought it. The IMSB was replaced at time of purchase and there was no debris in the oil filter until over 12,000 miles and three oil changes later.
- The sudden appearance of metallic debris was put down to residual debris from the original bearing having been lodged somewhere in the engine only to be ‘shaken loose’ at a DE event many miles later.
- However, after a further 500 miles – and no further DE events – there was still debris being produced. At this point the OP (despite some apparent earlier scepticism) shipped his car to Raby.
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone. However, we don’t really know, because there was no independent inspection of the LNE bearing. We have to take Raby’s word for it.
Why would I suggest a different cause to the one put forward in this thread? Because LNE bearings do suddenly fail due to manufacturing defects. My own Boxster S had such a bearing, and with exactly the same debris symptoms as the OP. On removal of the LNE bearing, I found one of the 18 ceramic ***** (it was a double row bearing) to be badly pitted with surface cracks. This one faulty ball was steadily eroding the steel bearing races, and was the sole cause of all debris. I replaced the IMSB with a standard SKF all-steel double row bearing at a fraction of the cost of a hybrid one. 6,000 miles later, no debris in the (standard) filter, on the magnetic sump plug, or in the sump…
Thought it worthwhile opening this thread again, given someone with the same symptoms might find the thread and not look to at least one obvious cause.
11-14-2018, 09:37 AM
#234
Rennlist Member
Sorry to revive an old thread, an interesting story with a happy ending for the OP but nevertheless a debatable ‘cause’.
Key points:
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone. However, we don’t really know, because there was no independent inspection of the LNE bearing. We have to take Raby’s word for it.
Why would I suggest a different cause to the one put forward in this thread? Because LNE bearings do suddenly fail due to manufacturing defects. My own Boxster S had such a bearing, and with exactly the same debris symptoms as the OP. On removal of the LNE bearing, I found one of the 18 ceramic ***** (it was a double row bearing) to be badly pitted with surface cracks. This one faulty ball was steadily eroding the steel bearing races, and was the sole cause of all debris. I replaced the IMSB with a standard SKF all-steel double row bearing at a fraction of the cost of a hybrid one. 6,000 miles later, no debris in the (standard) filter, on the magnetic sump plug, or in the sump…
Thought it worthwhile opening this thread again, given someone with the same symptoms might find the thread and not look to at least one obvious cause.
Key points:
- The OP’s car had a failing IMSB with metal particles in the oil before he bought it. The IMSB was replaced at time of purchase and there was no debris in the oil filter until over 12,000 miles and three oil changes later.
- The sudden appearance of metallic debris was put down to residual debris from the original bearing having been lodged somewhere in the engine only to be ‘shaken loose’ at a DE event many miles later.
- However, after a further 500 miles – and no further DE events – there was still debris being produced. At this point the OP (despite some apparent earlier scepticism) shipped his car to Raby.
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone. However, we don’t really know, because there was no independent inspection of the LNE bearing. We have to take Raby’s word for it.
Why would I suggest a different cause to the one put forward in this thread? Because LNE bearings do suddenly fail due to manufacturing defects. My own Boxster S had such a bearing, and with exactly the same debris symptoms as the OP. On removal of the LNE bearing, I found one of the 18 ceramic ***** (it was a double row bearing) to be badly pitted with surface cracks. This one faulty ball was steadily eroding the steel bearing races, and was the sole cause of all debris. I replaced the IMSB with a standard SKF all-steel double row bearing at a fraction of the cost of a hybrid one. 6,000 miles later, no debris in the (standard) filter, on the magnetic sump plug, or in the sump…
Thought it worthwhile opening this thread again, given someone with the same symptoms might find the thread and not look to at least one obvious cause.
11-14-2018, 10:23 AM
#235
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone. However, we don’t really know, because there was no independent inspection of the LNE bearing. We have to take Raby’s word for it.
Why would I suggest a different cause to the one put forward in this thread? Because LNE bearings do suddenly fail due to manufacturing defects. My own Boxster S had such a bearing, and with exactly the same debris symptoms as the OP. On removal of the LNE bearing, I found one of the 18 ceramic ***** (it was a double row bearing) to be badly pitted with surface cracks. This one faulty ball was steadily eroding the steel bearing races, and was the sole cause of all debris. I replaced the IMSB with a standard SKF all-steel double row bearing at a fraction of the cost of a hybrid one. 6,000 miles later, no debris in the (standard) filter, on the magnetic sump plug, or in the sump…
So enlighten us...
1. Did you have the LN Engineering bearing installed on your car?
2. How many miles on the bearing?
3. How did you determine without a shadow of doubt the metal laden oil was sourced from the LN bearing's races?
Look forward to your reply.
Last edited by NuttyProfessor; 11-14-2018 at 10:42 AM.
11-14-2018, 11:10 AM
#237
Rennlist Member
I read through the whole thread. One thing I’d like to point out is that tracking the car likely accelerated the already-present condition of debris in the engine from the original IMSB failure.
Raby proves again that there’s a method to the madness. He’s the expert, proven.
I’ve rebuilt engines in the past (non-Porsche). It’s absolutely essential to make 100% certain you don’t have any debris anywhere, anywhere, anywhere. It’s like a blood clot in your body that breaks loose. It’s not going to end well, or in the least, cause wear, but often a healthy excercise event can push the situation over the edge.
Glad to hear the rebuild was running strong years later. Not surprised, though. Do things right, it works.
BTW, it’s not all that bad to be paranoid. “Only the Paranoid Survive” is a book written by a founder of Intel corporation. Much better to be sensitive and open and proactive. But then after all that, just drive your car and whatever happens, happens.
Raby is like my real estate attorney. Tells me ten ways this thing is going to blow up and why I shouldn’t move forward. Then I say ‘thank you for that information,’ and I make my own decision on what to do next. And it’s not always what he recommends.
Raby proves again that there’s a method to the madness. He’s the expert, proven.
I’ve rebuilt engines in the past (non-Porsche). It’s absolutely essential to make 100% certain you don’t have any debris anywhere, anywhere, anywhere. It’s like a blood clot in your body that breaks loose. It’s not going to end well, or in the least, cause wear, but often a healthy excercise event can push the situation over the edge.
Glad to hear the rebuild was running strong years later. Not surprised, though. Do things right, it works.
BTW, it’s not all that bad to be paranoid. “Only the Paranoid Survive” is a book written by a founder of Intel corporation. Much better to be sensitive and open and proactive. But then after all that, just drive your car and whatever happens, happens.
Raby is like my real estate attorney. Tells me ten ways this thing is going to blow up and why I shouldn’t move forward. Then I say ‘thank you for that information,’ and I make my own decision on what to do next. And it’s not always what he recommends.
11-14-2018, 11:43 AM
#238
Drifting
The LN critic in 233 above has 25 posts to measure his knowledge of the M96 IMSB issue. How does that compare to the combined experience,knowledge and judgement of LN and Flat Six. ? I am an engineer who worked in engine development for a car company. Frankly ,I am humbled by the knowledge and skill of Charles.Jake and Baz. Post 233 is smarter than all of them ?
I have not bought anything from either company but through my own engine failure in similar circumstances to the OP, the LN+Flat 6 advice was flawless ,generous and unbelievably patient-even after I (foolishly)bought and fitted a competitors product .
. I challenged some of their suggestions but did it in the context of - I'm just curious - why is that ? We all learned about the M96 with that approach.
Post 233 above and others who piled on (in other Threads) is part of the reason we 'lost' Charles and Jake from this Forum. With their departure, their knowledge was lost also. The problem may be just one of poor expression perhaps ? Post 233 and others like it can be read as implying that LN and Flat Six are fools/thieves/other epithets. If that is incorrect , maybe the 233 needs to be modified ? At least note it is largely speculation ! Post 233 might have been useful if the poster had a more inquiring approach.
I have not bought anything from either company but through my own engine failure in similar circumstances to the OP, the LN+Flat 6 advice was flawless ,generous and unbelievably patient-even after I (foolishly)bought and fitted a competitors product .
. I challenged some of their suggestions but did it in the context of - I'm just curious - why is that ? We all learned about the M96 with that approach.
Post 233 above and others who piled on (in other Threads) is part of the reason we 'lost' Charles and Jake from this Forum. With their departure, their knowledge was lost also. The problem may be just one of poor expression perhaps ? Post 233 and others like it can be read as implying that LN and Flat Six are fools/thieves/other epithets. If that is incorrect , maybe the 233 needs to be modified ? At least note it is largely speculation ! Post 233 might have been useful if the poster had a more inquiring approach.
11-14-2018, 01:17 PM
#240
Instructor
Thread Starter
- The OP’s car had a failing IMSB with metal particles in the oil before he bought it. The IMSB was replaced at time of purchase and there was no debris in the oil filter until over 12,000 miles and three oil changes later.
- The sudden appearance of metallic debris was put down to residual debris from the original bearing having been lodged somewhere in the engine only to be ‘shaken loose’ at a DE event many miles later.
- However, after a further 500 miles – and no further DE events – there was still debris being produced. At this point the OP (despite some apparent earlier scepticism) shipped his car to Raby.
So how was original debris still appearing? According to Raby, “the most likely case is the original bearing failure process created material laden oil which has attacked the replacement bearing and is forcing its failure through greatly accelerated wear”.
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
Really? So even though this debris was apparently not circulating at all for 12,000 miles? Still there after three oil changes? And then causing no damage to the engine apart from the new IMS bearing and rod bearings?
As the OP, I differ in the thought process, the choice of three points you selected from the 17 pages of posts, and the conclusion.
We know that the shop that replaced the original bearing did not follow the LNE-recommended procedures to evaluate a replacement. When I talked to Raby and LNE they made it clear they would never have allowed the replacement. The shop is now on their black list and LNE will not do business with them again.
I've done my best to reconstruct the events into a narrative that passes the tests of math and engineering, Raby's experience through extended conversations and emails and his inspection and teardown of the engine, and my own observations. Is it the one and only possible explanation? No. But I think it's by far the most likely.
Without a complete teardown, it is impossible to remove all metal particles from an engine and find all points of wear. An oil change does not clear out all of the oil, and if metal particles are embedded on surfaces they will also not come out. So after the original IMS bearing was replaced by the first LNE bearing, it would be foolish to assume the oil was clean (which I did, and I admit I was foolish/naive). The shop claimed to have flushed the oil once (or twice maybe, I can't recall) until the oil was "clear". Today, looking back on the shop's behavior, I think we can all agree that was complete BS. There should be no question that after the original bearing replacement, metal contamination remained in the engine; maybe a very small amount, but not zero.
The default Porsche oil filter has a pressure valve that bypasses the filter when the oil is highly viscous, i.e. at startup. So the filter only works partially, and can't be expected to completely remove metal particles from the oil. And it could only filter particles in the oil, not those embedded in surfaces.
From this, I believe it is impossible to conclude that the oil and all engine parts must have been clean for 12,000 miles and three oil changes, to be suddenly shaken up by some event, DE or not. Furthermore, particles will be embedded on surfaces and not return to the oil. Yes, DE shakeup was one of my early theories, but I would treat it skeptically and look for better explanations, such as:
Metal particle damage is likely to be exponential. A certain percentage of particle content in the oil will cause some rate of additional wear, which produces more particles, which produces a higher wear rate, and so on. Classic exponential behavior. Put this together with the filter bypass and you have a highly believable case of a "sudden" growth of the exponential curve. Maybe the DE event accelerated it, maybe not, I really don't know. But we need to pay attention to exponential behavior: damage is growing at the same proportional rate all the time, but is not easily detectable until it crosses a threshold and then it "appears" to come out of nowhere all of a sudden. Think about the old questions about compound interest or how long it takes bacteria to fill the last half of a dish if it doubles each day. It only looks sudden, but the damage process has been going on for a long time.
It seems to me the more obvious cause of the new debris would not have been the original IMSB – replaced 12,000 miles previously – but the one now in the car. The current bearing would surely be many, many more times likely to be the source of newly-found steel debris in an engine than a bearing that is long gone
While you are right to point out another potential cause, in my case I think it extremely unlikely. Exponential wear behavior, oil filter bypass, and a dishonest shop that did the original replacement in spite of LNE's disallowing it are strong arguments to the contrary. If you can provide some evidence it would help bolster your argument.
BTW I'm now at 41k on the reconstructed engine with IMS Solution and as reported before, zero metal in the filter or on mag drain plug.
Last edited by mklein9; 11-14-2018 at 03:18 PM.