M97 IMS Bearing (what else, right?)

Hi Pedro, I have an 2008 987.1 S, "RS 60 Spyder". Like nearly everyone I am at least wary about the possibility of an IMS bearing failure. I'm aware that the bearing size on the M97 engine precludes easy removal/replacement as is possible on the M96 predecessor.

I have had several conversations about this with a Porsche tech whom I respect. He is acquainted with your kit and its task of maintaining optimal bearing lubrication. Here is his question:

"The bearings installed in the 9x7 engines are factory sealed and (according to studies) resistant to oil penetration unless completely submerged for long periods of time. How is this kit that sprays oil at the face of the bearing supposed to lubricate it internally, given that it is factory-sealed? Without replacing the bearing with one that is open-faced, all the oil sprayed at this 9x7 bearing will be shed, and be essentially inefficient. (This does sound like a nice retrofit for a vehicle with an LN Engineering open-face bearing.)

"I also am doubtful about the so-called 'blender effect'.If the bearing is submerged roughly half an inch in oil, it shouldn't whisk all of the oil off itself when it spins. If I put an LN Engineering bearing on my drill and submerge it half an inch in oil and crank it up, it won't throw all of the oil away from it if it's resting half-submerged in a reservoir of oil."

Pedro, I don't intend this to find fault with your solution. It just seems as if these are legitimate questions. I would very much appreciate your comments in response.

Thank you, Bob G

Quote
Bob G
"The bearings installed in the 9x7 engines are factory sealed and (according to studies) resistant to oil penetration unless completely submerged for long periods of time. How is this kit that sprays oil at the face of the bearing supposed to lubricate it internally, given that it is factory-sealed? Without replacing the bearing with one that is open-faced, all the oil sprayed at this 9x7 bearing will be shed, and be essentially inefficient. (This does sound like a nice retrofit for a vehicle with an LN Engineering open-face bearing.)

"I also am doubtful about the so-called 'blender effect'.If the bearing is submerged roughly half an inch in oil, it shouldn't whisk all of the oil off itself when it spins. If I put an LN Engineering bearing on my drill and submerge it half an inch in oil and crank it up, it won't throw all of the oil away from it if it's resting half-submerged in a reservoir of oil."

First of all, when a DOF Kit is installed with an existing OEM bearing, the procedure calls for the removal of the bearing's outer seal so that the oil stream can penetrate the bearing.
The bearing in the M97 is not replaced, just opened.

The bearing is submerged in about half an inch of oil when the engine is off, sitting on level ground.
Once the engine starts up and the oil starts to cling to all of the internal parts it's supposed to bathe, the bearing is not submerged anymore.
A bearing spinning at 2000 RPM and higher will shed most of the oil it had clinging to its surfaces.
Have you seen my latest video: [pedrosboard.com]

Happy Porscheing,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

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I have the same car. From what I understand, it is not reasonable to change the bearing in 2006-08 models because the engine has to be broken down to get to it. Don't know why, just have read this, Also read that the 987 is the 3rd version of the IMS bearing. Talking with my mechanic, an indy that I use and respect, if there are IMS failures in 987s they are rarer than earlier versions. So far. Time will tell. My guess/hope is that Porsche finally did it's best to solve the problem and hopefully we we will have many years of trouble free motoring -- as many others have had with the 2 earlier iterations of the bearing.

1999 Arctic Sivler/black/black (sold)
2008s Silver/black/black - so predictable
2011 Outback
8/24/2011 first Grandson

..whcih is how you get access to the M96s. Take off cover, using puller. Bearing supported by this cover at one end, other end on IMS shaft itself.

G

Grant

gee-lenahan-at-gee-mail-dot-com

My tech said that he has had to do only two M97 engine rebuilds, and the problem was not caused by IMS bearing failure.

But he affirms that if or when bearing replacement is required, the entire engine has to be torn down. Far more difficult than with the M96.

Thank you for answering the questions I posed, Pedro.