Schnell Gelb

This may be the failed bearing spec ?
"So, the parts I used for the IMS replacement were of course the Pelican kit which goes for $165 and the Boca ceramic hybrid bearing part # SMR6204C-2RS TH9/C3 #3 which goes for $69.95 (http://www.bocabearings.com/productd...px?ItemID=4260)

I'd love to take the credit for finding the bearing but the hard work and research credit goes to KrazyK and Imo000 (Imre). Those two pointed me in the right direction and gave me the pointers I needed to do it right. In the end, I decided to go the single bearing route as Imre's double bearing method required machine work to the snap ring and procurement of a specific sized spacer. I could have done it but since I'd already ordered the Pelican kit, I decided to go the single bearing route like KrazyK. It was simple. Just had to press the Pelican bearing off and press on the Boca bearing and install. So for around $235, I have a very nice IMS setup."
Source:
https://rennlist.com/forums/996-foru...g-install.html
http://www.bocabearings.com/productd...px?ItemID=4260

BUT ... the bearing may be O.K. - just inadequate pre-qualification/installation ?

996SPECticle

Sorry 'bout your luck.
You can't say he didn't address the IMSB.
You have vented which is an important step.
Have a drink.
Sleep well.
Get over it.
Move on with life.
...don't trust a good deal half way across the county

I'll bet my sister's TXBar card no Atty. would take this up, well maybe if they see you as the easy mark.

sweet victory

Am I the only one who looked up Boca Bearing and thought, "Why the hell would anyone put one of these bearings in their Porsche?"

Arch1t3ct

Definitely not, everything about that just seems questionable. There is a reason why the real replacement bearing costs many hundreds of dollars. There is also a reason why you don't don't take shortcuts on engines costing many thousands of dollars, as this thread has been a prime example of.

Schnell Gelb

Why use the BOCA bearing you ask ?
Probably because the specs match/exceed the OEM part. That is the point of the discussion. There is more to this issue than mere specifications.
Here are the specs for the failed bearing. Which specification is deficient? O.K. we can think they are counterfeit bearings or Q.C. rejects .But just focus on the paper specification. They seem fine to me.
http://www.bocabearings.com/productd...px?ItemID=4260

JayG

Is Boca bearing like Boca Burger?

Cuda911

Interesting info, Schnell Geb. Do you have a list of the specifications for the OEM one? I wonder why the Boca rep specifically stated that this bearing would fail if used in this application.

sweet victory

Before I even go digging for my machine design textbook, the company doesn't even have an iso certified quality management system. (At least that I could find) Just going based on that, I would not do business with them.

In my profession, I couldn't even legally use this company as a vendor.

sweet victory

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.

sweet victory

For those interested the information provided came from a textbook with ISBN: 978-0-07-339820-4 and was used in an ABET accredited M.E. undergraduate program.

Schnell Gelb

Here is the Timken catalog for this size/spec.You can configure your own 'upgrade' with the info here - start at p14.
http://www.timken.com/en-us/products...alog-10857.pdf
But it may be that even the best bearing from Timken/SKF etc. would have failed because the limiting factor was not bearing specs,ABEC numbers, nor quality control.
Remember that 92% (?) of the allegedly low spec OEM IMS bearings had no problem for 100.000+ miles (?)
Other threads with knowledgeable contributors have mentioned many other issues beyond mere specification.
The load vs.lubrication issue has been discussed many times. IIRC the last 'new' cause of failure was alignment.

groovzilla

I'm getting tired

dgi 07

Guys, lets stop arguing the semantics behind the bearing and get back to the relative topic at hand.

OP, next time you are in Northern NJ around giants stadium, hit me up and we'll go for a cruise. is on me. Sucks but you might as well drive your car and enjoy it.

RRTEC

there are several factors not being considered here..

1) the sealed bearing had it's seals removed... There is a debate on if the oil is sufficient in lubrication of the bearing..

2) without the seals any foreign matter could have infiltrated the bearing and caused failure. No?

The paperwork on the bearing used indicate it at minimum met the stock spec. Perhaps it just didn't like the modifications made to its original design.

rolex11

I will be the first to send a personal check for $100 to C4911 to fund a lawsuit in this matter.

Who else will?