997 engine numbers, registration dates and IMS bearings...
Discussion
Ok, another IMS related thread (sorry if you're fed up with these).
I got the following information from another forum and was wondering if anyone can confirm if it's correct and all applies to the UK (the post was from a Canadian) and also what registration date would closely indicate the point of change (I believe some time in 2005 - 2006). Finally, does anyone know of/has experienced a bearing failure on a 2006 onwards car, as apparently the larger bearings are much stronger? Thanks for any help!
'From the 997 work shop manual I extracted the following information on which engine has the smaller or revised larger IMS bearing:
Base engine (3.6) has designation "M96", can have the smaller IMS or revised larger bearing, you will need to know your engine number in order to determine which one you have:
Engine (3.6) number up to M96/05 69507475 has the smaller IMS bearing and Engine number from M96/05 69507476 has the larger revised IMS.
"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.
The smaller IMS bearing can be replaced, this requires removing the transmission in order to get access to the bearing. The flange uses a 13mm center nut.
The larger IMS bearing can also be replaced but a tear down of the engine is required. The flange uses a 22mm center nut.'
I got the following information from another forum and was wondering if anyone can confirm if it's correct and all applies to the UK (the post was from a Canadian) and also what registration date would closely indicate the point of change (I believe some time in 2005 - 2006). Finally, does anyone know of/has experienced a bearing failure on a 2006 onwards car, as apparently the larger bearings are much stronger? Thanks for any help!
'From the 997 work shop manual I extracted the following information on which engine has the smaller or revised larger IMS bearing:
Base engine (3.6) has designation "M96", can have the smaller IMS or revised larger bearing, you will need to know your engine number in order to determine which one you have:
Engine (3.6) number up to M96/05 69507475 has the smaller IMS bearing and Engine number from M96/05 69507476 has the larger revised IMS.
"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.
The smaller IMS bearing can be replaced, this requires removing the transmission in order to get access to the bearing. The flange uses a 13mm center nut.
The larger IMS bearing can also be replaced but a tear down of the engine is required. The flange uses a 22mm center nut.'
You can replace the IMS as part of preventative maintenance or do they just let go at random?
The RMS doesn't scare me one but the IMS was a really put off. If it can be replaced at a certain mileage to give me (say) another 60,000 before it needs doing again then I'm suddenly really interested in late 90's 911s...
The RMS doesn't scare me one but the IMS was a really put off. If it can be replaced at a certain mileage to give me (say) another 60,000 before it needs doing again then I'm suddenly really interested in late 90's 911s...
Thing is they go at all sorts of mileages. There is (was) a school of though that if they've not gone by something like 30k they'll be OK, but then some owners have had bearing failures at 60k. Read the Hartech pages on the subject - Baz has gone to a lot of effort to publish his experiences over the years.
http://www.hartech.org/porsche_996_997_Boxster_fre...
http://www.hartech.org/porsche_996_997_Boxster_fre...
Magic919 said:
Later cars need a lot more stripping down to get to the IMS bearing. With normal labour rates it's not really worth doing. Besides, the car is still as likely to suffer with bore scoring.
IMS failure and bore scoring both mean the engine's unsaveable don't they?IRRC you can't get the bore reground or new liners fitted like you would in old cars. Is this right?
It's just 911s are so cheap for what they are that at the moment. I was trying to work out if a rebuild at say 100K might give another 100K of use. I don't mind spending up front it's just I get the impression that a newer lower mileage car isn't likely to be any more reliable than an older one.
Or would I be better off looking at Jaguar and Maserati instead?
Hmmm, so what would be the preferred option out of:
a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
scoobysnacks2 said:
Hmmm, so what would be the preferred option out of:
a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
It's not cast in stone that a replacement or upgrade won't fail as well.a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
I had the LN Engineering upgrade done on a 2002 2.7 Boxster.
The bearing that was removed was in immaculate condition after 60,000 miles.
The work cost £1400 and I had a new flywheel fitted at the same time.
I've no complaints about the work or cost, it was my call and, if I had to again, I'd make the same call.
When I was looking at a Cayman I spoke to the same specialist and was advised that an '07 Cayman 2.7 had the best version of the IMS and not to worry. Two years and a lot of miles later and all is well.
Anything after 2006 is a safe bet, go smaller (2.7) and you safeguard yourself even more (less chance of bore scoring and localised overheating)
If you're unsure speak to Autofarm or Hartech about it.
scoobysnacks2 said:
Hmmm, so what would be the preferred option out of:
a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
That's a very good question.a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
There's also option 3. Buy the cheaper car and hold on to the savings just in case.
CDP said:
scoobysnacks2 said:
Hmmm, so what would be the preferred option out of:
a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
That's a very good question.a) Go for a later 2006 model with a stronger bearing in the knowledge that it's less likely to break and take your chances (as it costs too much to replace)?
or
b) Save some money and buy an earlier model with a smaller bearing and more cheaply replace the bearing with a 'better than 2006 model uprated one' (probably spending more than the above option in the process and ending up with an older cheaper car)?
There's also option 3. Buy the cheaper car and hold on to the savings just in case.
There's also option 4 which is to buy a 996 Turbo for about 997 Carrera S money...
A 2007 Porsche Boxster S with 27,000 miles and new engine, was for sale on Autotrader August 2013, this car had the uprated IMS bearing.
I emailed owner asking whether engine failure was IMS related, see email, these uprated bearings are still failing at various mileages. I sold my Sept 2005 Boxster S with 15,000 miles, the car had uprated bearing that needs engine teardown if bearing shows signs of failing, I could not stand the anxiety or the cost of bearing failing or the cost of remedial action. This type of bearing should never have been placed within the engine especially if its failure would cause catastrophic damage to the engine.
scoobysnacks2 said:
Yes, the bore scoring issue definitely seems more prevalent on 3.8 cars, which is steering me slightly towards a 3.6.
I ran an October 06 56 plate 997.1 C2S tip coupe to 27k miles without any issues...Also ran a December 07 57 plate 997.1 C4S tip cab to 13k miles when it piston slapped a matter of days before the 2 year Porsche warranty expired.....
..engine rebuilt by OPC ( as opposed to renewal which would have had a warranty), car ran perfectly for 6 months then sold.....
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