When was big IMS bearing fitted

[fillpoke2]

I believe a bigger and stronger IMS bearing was fitted at some point to 987 3.2S cars. Does anyone know the date/chassis number from when this was fitted? Or how to tell if the stronger bearing is fitted? Thanks, Dave

[Budflicker]

I might be wrong, however my understanding is that all Caymans have a revised IMS bearing.

As do 997 cars after 2006.

Bore score is the only real issue on gen 1 Cayman engines, but I think the 3.2 is less susceptible than the 3.4.

[V800MJH]

I have no idea for sure, but my understanding was that it was done just before the 987.2. Therefore all 987.2 have the upgraded part and a few of the last 987.1 do.

[PDKSport]

My INDY tells me from 2007.
Cheers.

[PDKSport]

My INDY tells me from 2007.
Cheers.

[DavidJG]

V800MJH said:

I have no idea for sure, but my understanding was that it was done just before the 987.2. Therefore all 987.2 have the upgraded part and a few of the last 987.1 do.

Err, no. 987.2 has the later engine that doesn't feature the IMS bearing at all. Cam chains on the 987.2 are driven directly off the crankshaft.

All 987.1 3.4s all have the larger IMS bearings.

3.2s are a bit uncertain. I've got a mid 2005 3.2, that had the small bearing which has now been replaced with the LN upgraded IMS bearing. The guys who did the bearing upgrade for me did say before we started that "There's no guarantee that we can upgrade the bearing, we won't know whether it's the small or large bearing until we take the flywheel off."

3.2 is ideal for me, I can fit an upgraded bearing (the larger one does fail, but can't be upgraded without splitting the crankcase) and 3.2s don't seem to suffer with bore scoring....

[V800MJH]

DavidJG said:

Err, no. 987.2 has the later engine that doesn't feature the IMS bearing at all. Cam chains on the 987.2 are driven directly off the crankshaft.

All 987.1 3.4s all have the larger IMS bearings.

3.2s are a bit uncertain. I've got a mid 2005 3.2, that had the small bearing which has now been replaced with the LN upgraded IMS bearing. The guys who did the bearing upgrade for me did say before we started that "There's no guarantee that we can upgrade the bearing, we won't know whether it's the small or large bearing until we take the flywheel off."

3.2 is ideal for me, I can fit an upgraded bearing (the larger one does fail, but can't be upgraded without splitting the crankcase) and 3.2s don't seem to suffer with bore scoring....

Thanks for clearing my thoughts up :-) I was obviously just on another planet when typing that!!

[Richard Hamilton]

You can tell by the IMS bearing cover. I extracted this from the 987 workshop manual - the notes are based on the engine numbers as they are shown in the manual.



And here is the same for the 3.6 997s:

Edited by Richard Hamilton on Saturday 10th November 15:31

Edited by Richard Hamilton on Saturday 10th November 15:36

[Heaveho]

I have an '05 Boxster 3.2S. The last digits in the engine number are 5848.

If the previous post is correct, I'm a bit happier about my prospects as an owner going forward!

Edited by Heaveho on Tuesday 20th November 20:10

Edited by Heaveho on Tuesday 20th November 20:13