Budget IMSB Retrofit for $165 Thread
#61
RRTEC, are you sure you want to do a similar experiment? I know that the LN bearings are not cheap but the dual-row ceramic has perfect record with a huge install base. Remember your whole engine is riding on that bearing.
#62
Actually no I don't want to experiment.. I thought I was swapping for a stock bearing as mine has been good for so long. But if this isn't a stock bearing then no... I won't be putting it in.
#63
I see but I've never seen a credible source that discloses the p/n of the exact bearing Porsche used.
#64
You are better off buying a tried and true part RRTEC.
#65
I don't think Porsche used an off the shelf bearing. I found a picture of an IMSB that has an NSK bearing with a suffix attached to it that doesn't exist in their catalog. I know other brands (sfk for example) have a suffix to indicate a deviation or modified internal design with the same boundary dimensions. Interesting stuff.
You are better off buying a tried and true part RRTEC.
You are better off buying a tried and true part RRTEC.
#67
My understanding is the dual row has perfect record, regardless of year. Quote from LN:
"Considering all three revisions of the IMS found in the M96 and M97 are known to fail, we know the use of a ball-bearing was a manufacturing constraint and a poor choice. That said, even the addition of a ceramic hybrid ball-bearing with its superiority over conventional ball bearings does not eliminate completely the chance of failure. Only the IMS Solution provides a permanent, worry-free solution to the IMS problem. With zero failures of our Dual Row and Single Row Pro IMS Retrofits, triple bearing IMS Upgrade, or even with our upgraded ceramic hybrid bearings used in the model year 2006 through 2008 intermediate shafts, we have almost a perfect track record, however there have been isolated single row IMS Retrofit kit issues, due to excessive thrust load wear that has been found after evaluating these rare instances. However, we still have a near perfect success rate even considering most failures are due to improper installation, failure to properly qualify an engine or are collateral damage from other failures (there are dozens of confirmed modes of failure for the M96 and M97 engine that can damage or cause your IMS bearing to fail)."
Source http://imsretrofit.com/ims-101/
"Considering all three revisions of the IMS found in the M96 and M97 are known to fail, we know the use of a ball-bearing was a manufacturing constraint and a poor choice. That said, even the addition of a ceramic hybrid ball-bearing with its superiority over conventional ball bearings does not eliminate completely the chance of failure. Only the IMS Solution provides a permanent, worry-free solution to the IMS problem. With zero failures of our Dual Row and Single Row Pro IMS Retrofits, triple bearing IMS Upgrade, or even with our upgraded ceramic hybrid bearings used in the model year 2006 through 2008 intermediate shafts, we have almost a perfect track record, however there have been isolated single row IMS Retrofit kit issues, due to excessive thrust load wear that has been found after evaluating these rare instances. However, we still have a near perfect success rate even considering most failures are due to improper installation, failure to properly qualify an engine or are collateral damage from other failures (there are dozens of confirmed modes of failure for the M96 and M97 engine that can damage or cause your IMS bearing to fail)."
Source http://imsretrofit.com/ims-101/
#68
Three Wheelin'
Disclaimer: after a few vodka shots.
KK's situation is really a great psychological case to study. Whether it is Murphy's Law or " you attract what you think" I can't help but wonder about this situation. KK never drove his car, constantly disassembled his engine to clean dust and replace working parts...all because he feared CEF. All he posted about was CEF and was completely paranoid about M96 engine. His car suffers CEF, unfortunately, with the new owner. Situation like this make me truly believe that positive thinking and positive energy do transfer to material things.
KK's situation is really a great psychological case to study. Whether it is Murphy's Law or " you attract what you think" I can't help but wonder about this situation. KK never drove his car, constantly disassembled his engine to clean dust and replace working parts...all because he feared CEF. All he posted about was CEF and was completely paranoid about M96 engine. His car suffers CEF, unfortunately, with the new owner. Situation like this make me truly believe that positive thinking and positive energy do transfer to material things.
#70
Rennlist Member
I am cross referencing my post to this thread so others do not make the same mistake as KK.
The information I'm about to talk about is not in the spec sheet. I had to use one of my textbooks from college to get this information.
This chart is used to determine your dynamic and static load rating for an equation used to figure out the life cycle of a bearing. Before I did any math, I noticed the load ratings are very similar, indicating to me the bearing KK used appears to be a 02 series deep groove ball bearing.
All bearing part numbers are made up of a type code, series, and bore. The second digit is what we're interested in as that indicates the robustness of the bearing. A number 2 series bearing indicates it should only be used for light duty applications. The item ID for the bearing used is 6204. The 6 indicates it is a roller ball bearing, 2 for light duty, and 04 for a 20mm bore. (Except for 0 through 3, the bore size is simply five times the third and fourth digits together) The spec sheet and item ID lead me to conclude the reason the bearing failed is that it's only a light duty bearing. As a mechanical engineer, and a human being with common sense, would not recommend this bearing for this application.
The information I'm about to talk about is not in the spec sheet. I had to use one of my textbooks from college to get this information.
This chart is used to determine your dynamic and static load rating for an equation used to figure out the life cycle of a bearing. Before I did any math, I noticed the load ratings are very similar, indicating to me the bearing KK used appears to be a 02 series deep groove ball bearing.
All bearing part numbers are made up of a type code, series, and bore. The second digit is what we're interested in as that indicates the robustness of the bearing. A number 2 series bearing indicates it should only be used for light duty applications. The item ID for the bearing used is 6204. The 6 indicates it is a roller ball bearing, 2 for light duty, and 04 for a 20mm bore. (Except for 0 through 3, the bore size is simply five times the third and fourth digits together) The spec sheet and item ID lead me to conclude the reason the bearing failed is that it's only a light duty bearing. As a mechanical engineer, and a human being with common sense, would not recommend this bearing for this application.
Just so you know, the 2 you mention is the series, agreed it is classified as light duty (a 3 would be medium duty), but you can't put any other bearing in the IMS. The 04 controls the ID of the bearing, the series controls the OD of the bearing. So if you went with a 6304, it wouldn't fit.
The bearing is not wrong.
#73
Rennlist Member
Here is what I am talking about. If you look at all the bearings in this picture, they are all mounted on the same shaft, so the ID of each bearing will be the same.
However, the OD of each bearing varies greatly because the cross section is different, so you can't change a 6204 for a 6304, they are not the same dimensions:
<img src=http://audipages.com/911/bearing.JPG>
Here's another picture showing a 6303 next to a 6203. They both have the same ID, but their OD is controlled by the load rating, the 6303 can carry more load, so it has more *****, a larger width, and a larger OD.
<img src=http://audipages.com/911/bearing2.JPG>
Hope this clears up the misconception that the "wrong" bearing was used, it wasn't. It was a like-for-like mechanical fit.
However, the OD of each bearing varies greatly because the cross section is different, so you can't change a 6204 for a 6304, they are not the same dimensions:
<img src=http://audipages.com/911/bearing.JPG>
Here's another picture showing a 6303 next to a 6203. They both have the same ID, but their OD is controlled by the load rating, the 6303 can carry more load, so it has more *****, a larger width, and a larger OD.
<img src=http://audipages.com/911/bearing2.JPG>
Hope this clears up the misconception that the "wrong" bearing was used, it wasn't. It was a like-for-like mechanical fit.
#74
This was from back in APR 2013. Is the documentation of the retrofit posted in another thread?
I'm starting research for my IMSB replacement.
Thanks.
#75
Woah - talk about coming to the party late!
Just getting caught up in YESTERDAY's developments on Rennlist (https://rennlist.com/forums/996-foru...g-story-8.html ).
Coincidence that this present thread and C4911's unfortunate purchase thread both came up.
Looks like I'll need to read about this issue in greater depth.
Just getting caught up in YESTERDAY's developments on Rennlist (https://rennlist.com/forums/996-foru...g-story-8.html ).
Coincidence that this present thread and C4911's unfortunate purchase thread both came up.
Looks like I'll need to read about this issue in greater depth.