Originally Posted by amg-jerry
OP - LET will replace the failed pulley and the damaged crank pulley (when we spoke you didn't mention the crank pulley was damaged).
I'm still not 100% sure that the bearing was at fault due to over spinning.
Over torqued idlers have been seizing for many, many years.
I have personally put 30,000 miles on my C32 with the same bearing that you had fail with no issues at all. Others have done the same...
Now, take a simple Google search for "Seized idler pulley" and you get tons (7,090) of listings where idlers have seized.
Google Search
There is even MBWorld listings for C32's without our product installed that have had a seized idler.
Link to listing on MBWorld
I understand your frustration and I did everything I could to help get the car on the road. I have taken proper measures and offered to replace the LET parts on the car.
Parts were installed Memorial Day weekend 2008, with LET-supplied instructions, proper tools, and the MB DVD shop manual.
If a bearing is rated to 15K max rpm, and is intermittently subjected to 18K+ rpm over the span of several months and thousands of miles (8+), isn't the logical conclusion for premature failure that the bearing couldn't handle the application? If 20K bearings are available in this application, why were those not initially spec'd for the LET Motorsports idler pulley?