Definitive Word on IMS

Definitive Word on IMS

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Johnny5hoods

Original Poster:

499 posts

118 months

Monday 4th January 2016
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Greetings,
Been thinking about getting a Porsche 986 2.7/3.2 for quite a while now. Probably late pre facelift/ early face lift. Aware that IMS is the only real risk with these cars. Read MANY PH posts regarding the subject, going back more than a year now, and all I can say is, I still don't know quite what I should do re IMS if I pull the trigger on one of these cars. I've read, and highly appreciated, more than a few posts and replies from Cmoose (are you a writer?) and Baz of Hartech fame. But it seems, as time's gone by, that there just isn't a clear consensus. First, it seemed fitting an upgraded, larger single row bearing was the way to go. Later, LN Engineering delivered the ceramic bearing, which many swore by - for a time. Then, an American Indy claims it's got nothing to do with the size of the bearing and is actually a lubrication problem. He invents a Direct Oil Feed kit, which squirts oil directly at the bearing, but not all are convinced. You've probably already seen the video, but here it is anyway:

https://www.youtube.com/watch?v=hzUq2DFpeKw

Hartech then kindly respond, saying the following (two thirds down the page):

http://www.pistonheads.com/gassing/topic.asp?h=12&...

I continue researching, and I find a couple of excellent articles detailing DIY clutch and IMS bearing change:

http://boxsterguide.blogspot.co.uk/2010/09/interme...

And:

http://www.mikesspecialtyautomotiveservice.com/ste...

Looks do-able. Tempted to have a go myself if I buy some pork.

However, I think Hartech, if I've understood correctly (many apologies if I haven't; I've certainly been wrong before and I might be wrong this time), advise against changing the IMS bearing in situ, as they say this can cause damage. So now I'm wondering whether upgrading a bearing, in situ, for a bigger single row or ceramic bearing would be wrong.

Then I learn from Baz that taking the seal off the bearing helps considerably, and the chain and sprocket throw up more than enough (cool, filtered) oil to replenish the bearing with oil, at a faster rate than the bearing itself can eject it (and I'm no engineer, but I believe him). But that leaves me asking whether the seal can be taken off the bearing without taking the bearing out of the shaft/engine. Does anyone know?

So, most excellent and learned PHers, I would like to think I have boiled down the whole IMS choice/debacle/guessing games to the following questions. If you care to reply to this post, perhaps you could vote on which one you prefer.

Is it best to:

1. Do nothing and hope for the best (we're talking about a 2001-2003 car here).

2. Replace small single row bearing, in situ, with upgraded larger single row bearing, leaving seal in place.

3. Ditto, but without seal.

4. Replace small single row bearing, in situ, with LN Engineering ceramic bearing, leaving seal in place.

5. Ditto, but without seal.

6. Install aformentioned American Indy's Direct Oil Feed kit (or a similar remote oil feed solution offered by competitor LN), presumably (?) without seal.

7. Simply take seal off existing bearing, if indeed this can be achieved without taking bearing out of shaft.

8. A combination of any of the above!

9. None of the above!

As you can tell, I do not know what the definitive word on the IMS debacle is. But I would like to know. And due to the nature of many Boxsters (and 996s, for that matter) being low mileage second cars, this is an issue which is likely to affect buyers for many years to come; ten plus years at least.

So I think we really need to nail this one once and for all. Thanks for reading this long winded post, and very many thanks for any replies.

Johnny5hoods

Original Poster:

499 posts

118 months

Monday 4th January 2016
quotequote all
Forgot to say, I've seen in the above mentioned DIY articles, and elsewhere, instructions for putting new bearing into freezer overnight before changing, and then tapping it home gently with a rubber mallet. This gives me added confidence that this is a do-able job. Have any of you changed your own IMS bearing, in situ? Did it go in OK without any damage?

bgunn

1,416 posts

130 months

Monday 4th January 2016
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Surely the safest way is buy a pre '2000 car with the double row bearing and the chances of failure are much lower anyway. It's not as if an 01-03 car adds *that* much at any rate, and low mile/good condition cars are out there (I bought a 66k mile 1999 2.7 a couple of months back).

poppopbangbang

1,785 posts

140 months

Monday 4th January 2016
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bgunn said:
Surely the safest way is buy a pre '2000 car with the double row bearing and the chances of failure are much lower anyway. It's not as if an 01-03 car adds *that* much at any rate, and low mile/good condition cars are out there (I bought a 66k mile 1999 2.7 a couple of months back).
Based on my experience this is true. I'm coming up to 290K miles on the original dual row IMS bearing in a 996. The earlier cars with dual row IMS and ferrous piston coatings do seem to be fairly bomb proof.

griffter

3,981 posts

254 months

Monday 4th January 2016
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Fantastic post, well done. About time somebody reviewed and consolidated the story so far.

My vote is for 5 (LN bearing is uprated quality if not size), if removing the seal is applicable. I don't think 7 can be done because the seal is on the internal face.

However in practice I'm considering 1. Mine has lasted 40k miles and I only do 3k a year. Is it a risk I am prepared to take? Possibly. The implications of a failure are huge, but then the whole engine gets rebuilt and future proofed.

It's worth trying to find THE solution imho because limiting the choice of cars further based on model year further narrows the already very limited pool of good cars if you're being particular.

DavidJG

3,507 posts

131 months

Monday 4th January 2016
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I went with the LN engineering upgrade option. This is an uprated bearing, without the internal seal so lubricated from oil spray from the crankcase. Personally, I like LN for the reason that they actually state that the bearing has a service life and requires periodic replacement. As I've said elsewhere, this is what Porsche should have done originally. Had the IMS bearing been treated as a service item it certainly wouldn't have the reputation that it has today. It's not a hugely expensive item to replace - it's cheaper than replacing the cam belt on a Maserati turbo V6.






griffter

3,981 posts

254 months

Monday 4th January 2016
quotequote all
DavidJG said:
I went with the LN engineering upgrade option. This is an uprated bearing, without the internal seal so lubricated from oil spray from the crankcase.
That's interesting. I didn't know the LN bearing used splash lubrication. What's the service life? I understood it was 40k (which I could sustain) or 4 years (which I could not).

DavidJG

3,507 posts

131 months

Tuesday 5th January 2016
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griffter said:
That's interesting. I didn't know the LN bearing used splash lubrication. What's the service life? I understood it was 40k (which I could sustain) or 4 years (which I could not).
That's correct - LN recommends 40k / 4 years. The four year thing seems short, especially as I do less than 5k a year in mine - but it's really not that expensive to change out, it works out at < £250 / year.

As I have a later, single-row car, not uprating the bearing wasn't an option. Hartech have one view on this, that it can add stress to the engine, however the single row bearing seems to have a high failure rate, so is worth changing. There's no definitive answer that I can see, but enough people are changing these bearings to upgraded items without problems to make me think that it's a worthwhile upgrade, and probably reduces the risk of an expensive failure.


Mogul

2,925 posts

222 months

Tuesday 5th January 2016
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anonymous said:
[redacted]
The weakness with this approach is that the clutch would quite easily outlive the engine, shirley?

hartech

1,929 posts

216 months

Wednesday 6th January 2016
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The IMS problem (or solution) is now largely a question of risk analysis and the circumstances and skills of the owner.

The first failures we ever experienced were with double row bearings. It is well reported that "IF" they survive long enough to wear the seal sufficiently to allow some oil ingress from the available spray - then they can continue for much longer - this can explain why some think the dual row bearing is better as the early failures are well behind us and those left lasted long enough to keep going for longer. The same delay in failures is now applying to the single row bearing.

IMS bearing failure is still lower than failures of bore scoring (later engines and the highest failure numbers), cracked cylinders (earlier engines), cracked heads (earlier engines), chains breaks, crank bearing failures etc.

When a bearing has been running for a long time in a press fit hole the two surfaces can work against each other (especially when the bearing is a little under specified anyway) and if it is then removed it can further damage the surface that the new replacement bearing is being fitted into on re-assembly. This takes the shape of small surface areas with effectively friction welded spots and bumps that pinch the replacement bearing on assembly (so there is no chance of checking it after it has been replaced).

The earlier bearing had a sprung loaded internal clip that pops into a recess to secure the bearing and sometimes removing the bearing with a puller traps the spring and damages the internal surface of the housing.

Removal and re-fitting a new bearing can also push the existing chains slightly out of alignment during the process and the grooves the chains have cut into the plastic chain guides can be damaged as a result.

This does not make changing the bearing for a newer one more likely to fail but does introduce a small failure variable which may be little different in statistics to leaving it as it is (providing there are no signs of it having been worn or failing).

Removing the outer seal of an existing bearing is a good option (if the existing bearing seems OK) and the only danger then is to make sure the spindle is not strained when aligning the out spider carrier back into the location hole. This spindle has a weak spot where an "O" ring is fitted and is it unfortunate that at precisely the point that the spider fits on to the spindle the outer diameter of the spider fits into its location hole and both need the IMS to be pulled sideways to pull against the chain tension (even with the tensioners relaxed) to locate both in their respective holes.

If the bearing is being replaced you can use a puller or sliding hammer. The sliding hammer can be better as it shocks the spring clip at the same time as pulling on the bearing and can result in a cleaner removal - but if the latter you need to support the shaft so it is not pulled forward as the sliding hammer imparts loads to the shaft (an old spider suitably machined internally can do this job).

Later single row bearings are thinner and created space for a conventional circlip that a circlip removal tool can get out without damage.

We have replaced the IMS bearings in situ successfully (with various tool aids when it is clear that it is failing) and so although we could replace bearings with a very high degree of reliability - we are concerned if it is worth the risks involved and will not do so at our full risk if there are subsequent related failures and usually when we have explained our position, if the customers bearing shows no signs of failure - customers see the sense in waiting and keeping their fingers crossed.

The problem that could emerge is - what would happen if shortly after replacing the bearing in situ - something loosely connected to the job failed. For example a piece of the plastic runner broke of, snapped the chain and valves hit pistons etc - or the chain just snapped (perhaps it would have anyway) but what would the customer expect of the business that fitted the bearing for them in those circumstances. With the cost of removing, rebuilding and repairing such a resulting engine failure so high any business having just one major failure of this type shortly after fitting a replacement bearing in situ - would never recover enough profit from doing that same job again and again - to pay for just one major engine failure (even though it would not necessarily have been their fault). It might be worth the risk if IMS bearing failures were more common - but it begs the question - why should they take the financial and reputational risk when the risk of failure anyway is so low now that most of the original bearings will have covered sufficient mileages to keep going (especially with the outer seal replaced in situ). Any business that will fit a replacement system in situ under full guarantee (meaning if there was a subsequent failure that could be connected to that work they will rebuild the whole engine FOC and replace all damaged parts at no cost) - must be worth a punt if they are reliable enough to trust. Be wary however that some businesses offload their guarantees to a third party who then may refuse such a claim, have claim limits or other ways to wriggle out of responsibility. Although we are both trust worthy, have a great reputation and cover any claims under our own policy - we will not take that risk since we could never earn enough from each IMS bearing replacement job to cover that cost (we would have to do hundreds) and we judge the possibility of some related failure at lower than 25,000 miles after the "in situ" replacement - too high a possibility.

You need to add to this the fact that by 45K most 3.6/3.8 engines have crankshaft shells nearing the end of their wear thicknesses, by 60 to 90K most early 3.4's will have oval bores nearing their crack limit or cylinder heads with fatigue cracks growing, by 45 to 60K - most Cayman S, 3.6 and 3.8 engines will have piston coating loss, oval cylinders and be close to (or already be experiencing) bore scoring so for many an engine strip may be imminent anyway and some have replaced the bearing only to have the engine in bits some time later for another reason when they could have waited and fitted the better large bearing version anyway.

The differences in driving styles, speeds, loads, quality of care, oils plus random production variances means that although we realise that there are a lot out there that have covered very high mileages without failure - readers would benefit from not paying too much attention to the contributors that have experienced very high mileages reliably - because the failures that do occur will depend on so many variables that such anomalies will always be experienced by some lucky owners - but by themselves this does not in any way nullify the experiences of those owners who had various failures with new cars at very low mileages nor does it negate the numbers that are being repaired for typically the same few technical failures Worlwide. Risk assessment is difficult but a small number exceeding the norm does not mean the average failure rates don't exist and therefore does not mean there is actually no risk - and are just typical of any statistical analysis.

The risk that this engine range will fail at lower than expected mileages is there but still in small numbers. For most failures the solution is long term (i.e. fitting a larger bearing during a rebuild) but since the ideal solution involves engine strip down and since there is some risk replacing the small bearing in situ - the odds about it being a worthwhile investment to change a perfectly sound bearing in situ for another that probably will be no better and allowing for the fact that the second bearing fit may not go in as nicely as the original and reduce life expectancy - are worse.

With the M96/97 models being excellent (apart from this slightly lower engine life expectancy than earlier models) and rebuild costs combined with future proofing benefits actually less expensive than the eventual rebuilds of previous models - set-against the low risk of an IMS bearing failure and the advantage of an upgrade to the larger bearing during a rebuild - the risk of doing nothing (or perhaps just removing the outer seal in situ) seems very little different to the risks of replacing the bearing in situ with some "upgrade kit" (that actually will probably not be any better than the original) seems worth taking.

For owners capable of tackling the task themselves - it may be worthwhile changing the bearing in situ as it is inexpensive and as long as they accept that there is a very small chance it may still fail - most will have given themselves peace of mind and at very little cost. For those relying on a business to change it the costs will be much more and the sheer variety of alternatives now available combined with the failures of some of those we see at quite low mileages introduces another risk factor on top of the potential for a full engine rebuild anyway in the near future.

In conclusion can I just say that apart from replacement during an engine rebuild for a larger bearing - anything you decide to do has some risk.

In my opinion the risk of removing the seal only is very low and the benefits quite high (especially if you can do it yourself). The risk of paying someone to replace the bearing in situ for a single row ball bearing are still low and probably worth the risk but is not fool proof.

The risk of replacing the existing small bearing with some other system could be a reduced or increased risk, be more expensive and none are sufficiently tested and proven over similar ages and mileages as the originals as the variety makes numbers replaced very small anyway.

If your model is one that has a higher risk of some other failure requiring a strip and rebuild one day - waiting until then and putting in a larger bearing system is a much more reliable solution and in my assessment a better risk.

Baz

Edited by hartech on Wednesday 6th January 14:49

Mousem40

1,667 posts

216 months

Wednesday 6th January 2016
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So with Baz' cogently argued advice in mind it may be worth considering option 10: IMS Guardian

http://www.wrightune.co.uk/imsguardian.html

This will give you an early warning in case the bearing does start to detonate so you can stop the car before serious engine damage is done.

hartech

1,929 posts

216 months

Wednesday 6th January 2016
quotequote all
That's a good point and as a matter of principle I would not criticise any system that warns of imminent damage and so will not criticise the Guardian product. However in our experience - most failures occur too quickly to be reliably warned against in time to prevent damage - usually on start up.

One failure mode is when the cage that separates the balls in the bearing cracks and bits go everywhere instantaneously. Some engine survive this (and it could be picked up by a Guardian system). In others the cage cracks and the balls all run round to one side of the housing where they rub against each other in a contra-rotating way that generates small wear particles (which I guess the system would pick up). Other simply explode and in seconds the damage is already done.

However if the resulting rebuild includes a new bigger bearing shaft or a re-manufactured bigger bearing shaft - the overall cost is often little or no different than if it was rebuilt after say a Guardian warning and this makes the cost of fitting it something to consider.

In an aeroplane such a system would be invaluable as you cannot land anywhere but in a car you usually can stop and organise recovery and this is an important inconvenience as most try to plod on somewhere and this is why most resulting damage then occurs.

Most engines we rebuild have not had the IMS bearing failure and we then replace it and remove the problem in the future - so in all those cases the guardian system would have made no difference - but - as with many things - if you can afford it and it stops you worrying - why not?

Baz

andy97

4,691 posts

221 months

Wednesday 6th January 2016
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I think I may look at 944S2 and 968s again, sill corrosion is easier to spot and deal with?

ZDW

60 posts

99 months

Wednesday 6th January 2016
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Baz,
when I read your posts on the IMS subject they seem to be the most sensible out there. I've often thought about what I should do with my 996 3.6 and it looks like I should bust not worry about it and drive the thing (when winter's over in 10 weeks- can't wait).

When clutch replacement time comes and I've access, I could do what you mention and remove the outer seal of the bearing. I'm not clear on how it helps if the inner seal is still in place. If you've a few moments could you elaborate?

great post. I'm sure everyone appreciates your time.

bgunn

1,416 posts

130 months

Thursday 7th January 2016
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ZDW said:
When clutch replacement time comes and I've access, I could do what you mention and remove the outer seal of the bearing. I'm not clear on how it helps if the inner seal is still in place. If you've a few moments could you elaborate?

great post. I'm sure everyone appreciates your time.
I am surmising that there's a gap between the end of the intermediate shaft, and the spider that supports the inner race of the bearing - so oil is sprayed out (by the chain) and works its way around to the outer edge of the bearing. After all, the *inside* of the bearing is actually inside the bore of the intermediate shaft, so the oil would have to come down the shaft to get there anyway..

hartech

1,929 posts

216 months

Thursday 7th January 2016
quotequote all
To be fair to me I always repeat how low the percentage of premature failures is and how great the cars are and in fact when statistics are quoted always point out that they relate to the life, age or mileage of the car and that during that period - it will have several owners that reduces the statistical chance of it occurring to you in your ownership by the average number of owners (say 4 or 5). So if failures before say 80K are (just as a guess) 5% and in that time and mileage there are (for argument sakes) 5 owners - that gives a 1% chance of you experiencing it in your ownership - and that is extremely low.

The crankshaft shells are of "average quality" but the forces put on them by some owners are very high (not much different to those experienced in similar sized racing engines of a few decades before). The change to nitride shallow case hardness depths also has an impact on the ability of the surface to resist "Brinelling". The shell areas are much smaller than the 944/968 crankshafts which were also fully hardened to a greater depth. The M96/97 oil temperatures that can exist in some circumstances reduces the film strength of the oil supporting the bearing and keeping the two metallic surfaces apart and the oil pump design does not provide good oil pressure at low revs where the delivered torque is far higher than previous models. The oil pump in the earlier air cooled 911's also delivered low oil pressure at tickover but they did not generally supply high torque at low revs and by the time you had revved the engine up to get some performance out of it - the oil pressure had risen to acceptable levels for the loads supplied and the crankshafts had a deeper hard surface (the Gen 2 engine has a much superior oil pump system).

Making engines that produce more torque, power and lower emissions while reducing manufacturing costs is a major headache for all performance engine designers and more pistons of a smaller diameter (and therefore individual lower loads and heat) reduce the individual loads on cylinder walls, crankshaft shells etc but an engine with big pistons will produce excellent torque from a relatively light and small engine with low inertia (and therefore great acceleration) - so is always a desire if it can be made sufficiently reliable.

To be fair to Porsche I doubt they envisaged a 3.8 squeezed into the 2.5 Boxster basic engine layout and external dimensions when they first designed the Boxster engine but as the earlier and smaller engines seemed reliable I can understand how they exploited that initial success to gradually expand the range and deliver fantastic performance to boot - they really have made a great car. However history is littered with previously perfectly reliable engines that the manufacturers slightly increased in capacity and revealed a weakness somewhere that they didn't have time to fix in that model production run - and this seems to fit that scenario with the added complication of the piston coating change (the reasons for which are not entirely clear but seem to have been imposed externally).

The boundaries they reached of the compromise between reliability and cost are little different to many other high performance sports cars - but admittedly not as good as previous examples - but then they still made the more expensive turbo and GT3 models that were more reliable while the relative cost of the M96/97 Boxsters, 996's and 997's was lower in "real terms" than those previous examples. You must also take into account when weighing all this up that they were going bust when making the 968 and 993 - so would have had to increase the price of those significantly to survive - while the model range we are interested in saved the business and has allowed it to go on from strength to strength and supply the cars we all love.

I feel sure that a consideration in all this was that in actual fact the vast majority of owners never drive with high throttle openings, high torque or high top speeds (particularly in the main market of the USA) and that inevitably driving a 160 mph car like a Ford Fiesta will make it last much longer and apart from the original and second IMS bearing design weakness and the enforced? change to the piston coating (and perhaps the lack of support for the top of the cylinder liners) - the rest of the car will survive most owners for perfectly acceptable mileages and reliability and still give owners an occasional blast without resulting in long term damage.

If the only solution for those experiencing engine problems was a new Porsche engine (with the same weaknesses) at I suppose around £16K (supplied and fitted) the value of the cars would make it a very bad situation indeed but with rebuilds possible around half that price that in some cases incorporate better quality technology that make the engine even more reliable than before (like Nikasil cylinders and larger IMS bearings) and not forgetting that purchase prices are much lower than they would have been if the engines had been 100% reliable - it seems to me that the whole scenario is acceptable as long as prospective used car buyers are aware of the small possibility of an engine failure and have worked out an escape route they can afford in advance (all be it personal reserves, reliable warranties, or simply taking the very small risk involved). If the engines had been more reliable the increase in values wuld have meant that many owners would not have been able to afford to own or enjoy such a fantastic car and most will get away with acceptable reliability in their ownership.

What I find is tragic is the owner that was not aware of the remote possibility of an expensive engine problem, sinks their last £ into buying their dream car and then cannot afford the resulting repair while losing faith in the Marque and having a nightmare experience - and that is why - when appropriate - we publicise the true position while putting it into perspective - on the Internet - when we can. It upsets some people but we believe that overall it is better to be informed than effectively "conned" through unrealistic expectations and better to be aware of the availability of a less expensive (and I would claim - more reliable) - way out - if they get caught out.

Regarding the inner IMS bearing seal - the only purpose (if there is one) was to prevent the original grease from leaking out and into the blind tube behind it. If that is also removed the splash oil can fill that tube for no purpose whereas by leaving it in place there are two advantages. (1) you do not need to actually remove the original bearing (so limiting potential damage in doing so) and (2) as the splash oil can only enter the bearing from the outside face - you provide a surface for the oil being splashed into the bearing from the outside to bounce back into the bearing again on its way out again.

There will always be some people who prefer to live in ignorance and/or believe that some manufacturers (or specialists) can do no wrong (even when faced with the obvious evidence that their own engine has failed or others repaired by specialists have also had their solutions faulted) and no amount of technical or evidential reporting will be gratefully received by them.

The easiest way to sell something is to tell people "what they want to hear" - and in most cases that is either that there is nothing wrong with these engines or that some IMS "upgrade" or cylinder solution or another is the "only answer" and many make a living from exploiting this fact of life by jumping on the band waggon with inferior solutions.

We are different. We understand the problems and have researched, tested and supplied solutions that for those who go into ownership with their eyes open benefit from knowing they bought a fantastic car at effectively a bargain price and that in some cases that risk backfired and they now need the reliable engine rebuild they always knew was a possibility anyway - while for most others they get away with reliable performance throughout their ownership- -what's not to like in that?

Baz






xjay1337

15,966 posts

117 months

Thursday 7th January 2016
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I was looking at buying a Coxster S before I ended up buying and modding my Scirocco.
Bloody glad I didn't now.

Porsche engines in their "normal" cars (I understand that turbo 911s and gt3s are OK) are very very fragile.

ras62

1,086 posts

155 months

Thursday 7th January 2016
quotequote all
hartech said:
You need to add to this the fact that by 45K most 3.6/3.8 engines have crankshaft shells nearing the end of their wear thicknesses, by 60 to 90K most early 3.4's will have oval bores nearing their crack limit or cylinder heads with fatigue cracks growing, by 45 to 60K - most Cayman S, 3.6 and 3.8 engines will have piston coating loss, oval cylinders and be close to (or already be experiencing) bore scoring so for many an engine strip may be imminent anyway and some have replaced the bearing only to have the engine in bits some time later for another reason when they could have waited and fitted the better large bearing version anyway.
January business a bit slow Baz;)

hartech

1,929 posts

216 months

Thursday 7th January 2016
quotequote all
Cynical or what - no just normal Internet responses to questions raised about the IMS problem and solutions and trying to convey information about choices.

We are dealing with a problem that affects a small number in which there are lots of different solutions and conflicting advice.

Whatever anyone thinks there is a risk that someone will experience a failure with the original or indeed and apparent "upgrade" (which in our experience is an incorrect description of other solutions we have also seen fail).

The risk is low and therefore when weighing up what to do for the best - I have introduced the fact that as the best solution can only be achieved by rebuilding the engine and as there is also a statistical possibility of that being required for not only the IMS bearing problem - but perhaps for other reasons as well and since all the cars are getting older and mileages are increasing - the reasons to consider accepting the IMS bearing risk and dealing with it if and when the engine fails (either for that or another reason) strengthen (or perhaps for only removing the outer seal rather than replacing the whole bearing and spindle etc for a new system).

I think if I was trying to drum up work I would be pushing the idea of replacing the IMS bearings with a solution we probably first manufactured before anyone else (and that has been copied by many since and has worked extremely well) and exploiting owners apparent paranoia about it and not supplying reasons why it might be better to do little or nothing about it!

Actually we are still extremely busy (more than last year) and have so many new projects on the go it is difficult to get everything done!

LOL Baz





Gandahar

9,600 posts

127 months

Thursday 7th January 2016
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I wonder how long the 991 GT3 engine will go, even after the eradication of the original problem. 9000 is a lot of revs.