997 IMS bearing

[OwenGarrigan]

Hi all, forgive me as I’m still pretty new to both 911s and to the forum. I bought my 2005 997 12 months ago and have been enjoying getting to know it. It’s a 2005 Carrera 2, with 50k on the clock and 2 previous owners. The previous owner had it boroscoped not long after he got it in 2010, and found scoring, and got a replacement block under Porsche warranty, I have the bills from Porsche Edinburgh.


It’s only done about 20k since the rebuild, one of the reasons why I was attracted to it. I am looking for advice as to how susceptible it may be to the IMS failure. Does anyone have a view whether when it was rebuilt in 2010, would the IMS have been replaced with a more robust solution, or will it be carrying the same risk as when it was new?


if it does, I would be keen to have a retrofit option fitted to minimise the risk of failure, but obviously don’t want to shell out for that if the risk has already been reduced appreciably.


Your advice would be much appreciated.

 

[Motorhead]

Hi Owen,

Do you know from the bills if the engine was just rebuilt with a new crankcase with other components replaced or carried-over, or was a short engine fitted? Either way, since it was a Porsche warranty repair it should have been built to the latest spec [including the IMS bearing], although I think that by 2005 your car would have had the last iteration of IMS bearing updates anyway.

For information and advice go to the Hartech website: https://www.hartech.org/

Jeff

 

[997Mike]

S” Engine (3.8) has designation "M97”, can have the smaller IMS or revised larger IMS bearing:
Engine (3.8) number up to M97/01 68509790 has the older IMS bearing and Engine number from M97/01 68509791 has the larger revised IMS.

Hope this helps

997 Mike

 

[OwenGarrigan]

Hi Jeff,

Thanks for the reply, from the bills it looks like some parts were replaced and other reused. I’ll check out the Harlech site also, thanks for sharing that.


Owen

 

[OwenGarrigan]

Thanks Mike, that’s useful - you made me realise I’d made a stupid mistake in my post, my car is not the ‘S’ it’s the 3.6 Carrera. Must have been having an odd moment when I posted it. Have edited the original post now to correct.


Owen

 

[Motorhead]

Hello again Owen,

Although online information is a bit contradictory it seems as though the last IMS bearing update was for MY2006 when the larger single-row bearing was introduced which is not serviceable without engine disassembly, unlike earlier versions, and which is not therefore compatible with the bearing fitted to the earlier engines.

On that basis, if your car was built late 2005 (MY2006) it should have the larger bearing fitted but I don't know if you can still use Mike's information for guidance.

Jeff