IMS oring M97 engine
 

Hi,
I am in the middle of changing the seal on my '07 CS IMS shaft. I cannot find anywhere the dimensions of the oring that goes on the shaft behind the 22mm nut. The 986's had a smaller shaft with a 10x1.5mm oring, but mine is considerably larger. No one seems to know. It is not shown on the Porsche parts diagram. I've asked on CaymanRegistry on the how-to article I am using, I've called LN Engineering, TPC Racing, Pelican Parts, local indy mechanics, taken it to auto parts store. No one can tell me exactly what I need to get. Has anyone done this job? I'm getting tempted to put the used oring back on but really don't want to go through this job again. I want to fix it right.

https://cimg4.ibsrv.net/gimg/rennlis...39c571303d.png
Are you talking about the rubber seal on the IMS "FLANGE" instead of shaft? The M97 bearing itself will also have a seal. (see part#15 in the diagram)

Please advise.

https://cimg8.ibsrv.net/gimg/rennlis...f3abd37e19.png


Here's the diagram showing the small O ring #14. Is that what you're talking about?

That appears to be right. No one else could find it on a parts diagram. 18x2mm sounds correct based on what people were measuring (not with great accuracy). That's probably it. That wouldn't happen to be the same size as the chain tensioner orings (part 25 in the 2nd diagram), is it because I could reuse one of those on the tensioner and use one of my new ones on the shaft?

Not sure if it's the same as used on the tensioner. But because they're so cheap, I'd order both versions for the IMS flange. Notice #14 has two different sizes.

Yes, but 7mm is way small. I bought 10mm as I'd read that the LN kit comes with that size, but that's for 986 engines and that was way too small. The way it says there are 2 sizes and 7mm being so much smaller worries me that it's not the right one, but this is the most i've got to go on, so hopefully I can find one locally. I do need Buna (nitrile), right?

That's a good question... not sure of the OE ring composition. It will definitely have to be in line with other manufacturers for this part because of it's exposure to engine elements (i.e. hydrocarbon, heat, etc.)

Here's a good deal on the package. Many people replace the outer Flange gasket too. In addition to this kit, I would recommend replacing the center nut of the bearing.

https://lnengineering.com/products/r...-ring-kit.html

Do you know the engine number (i.e. M97.XX) for your car? Did you say it's a 2007 Cayman S? You said "CS" and so I'm not sure if you mean something else.

If it's a Boxster or Cayman S for 07, then it should be the M97.21.

That would help confirm the design of the flange. It will be the 6305 bearing, but it appears they used different flanges? (see picture)
https://cimg1.ibsrv.net/gimg/rennlis...1b8f8516ca.jpg

It's the m97.21. I used the part # from the diagram you posted and found it at Pelican Parts after striking out about 10 places locally. No one sells this stuff. You have to get it from Porsche or Pelican. $45 overnighted for an oring as I'm sick of waiting to get my car back together. At least I found it. It had better be the right one! Thanks for finding that diagram for me.

Hope everything works out and you get your car back on the road!

Cheers! :cheers:

Thanks, I got it together today and it ran fine. Hopefully no leaks. Time will tell