Poll, Condition of my IMS bearing
 

Hi Everybody,

Ok I've decided to get my IMS bearing replaced with an LN Engineering retrofit. My car is a 2002 base (2.7) manual with 85K Kilometres on the clock (56K miles approx.)

I've only just got the car, and it is in great condition with nothing apparently wrong with the engine. There are no funny noises, the engine is strong, and I had a PPI done. However, the previous owner did the bare minimum of oil changes. I've just had it serviced, but the last oil change was about 4 years ago, at about 65K kilometres. Not ideal really.

Anyway, please place your bets on what condition my old IMS bearing will be in when I have it replaced on Friday!

http://986forum.com/forums/uploads01...1411360840.jpg

If it's not perfect the engine is already in trouble.

IMS Bearing
 

Three guesses what condition I'm hoping it's in :)

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More Forum clutter.

Sorry you feel like that. It's just meant to be a bit of fun, possibly at my expense if it turns out to be bad news.

Cheers anyway.

Ah, don't sweat it. Personally, to me, the whole point of these forums is to talk about our cars, whether we are sharing/asking technical questions or we just want to share a funny story or anecdote. Forums are open-concept (except for cats!) and all are free to share thoughts, ideas and yes, silly fun.

My IMSB was in perfect shape after 136,000 miles and 89 track days. Instead, lifter failure was caused the engine to fail. Best of luck but odds are very high that if your bearing had a problem, you'd already know it.

you say the bare minimum of oil changes were done? How many?


Another factor is how often was the car driven. a 12 year old car that saw about 4,500 miles might be good if the mileage came in somewhat frequent and year round trips. Not so great if they came from mostly summer time driving without having the oil changed after the driving season.

Did your PPI include a leak down test? That will tell you more (engine wise) than a visual inspection of just the IMS bearing, which really needs to taken apart to see what's doing (by someone who knows what to look for).

I would bet that it's probably in pretty good shape. I just had the retrofit LN bearing done a couple of days ago. My car is a 2001 2.7 and the previous owner had only done one oil change in 3 years. The car has done 36K miles. Here's the old bearing:

https://lh4.googleusercontent.com/-R...o/IMG_6579.jpg

I couldn't find any visible signs of scoring. Yours will probably look the same. However, the seals had leaked and there was no grease left inside, but at least it was well lubed by engine oil.

https://lh5.googleusercontent.com/-G...o/IMG_6543.jpg

Hope you can post some pics of your old bearing when the job's done.

If the tube was filled with oil and the seals compromised, then the bearing was at Stage II failure. Looks like it was caught at the perfect time, before wear increased and contaminated the oil supply. Once that happens, the health of the retrofitted bearing is seriously impacted.

I suppose the grease being washed out could be a 'stage' of failure, but if the bearing has engine oil to lubricate it, whats wrong with being in 'stage 2' failure for 150,000 miles?

That all depends on how fast the bearing progresses through the phases of destruction and if the bearing was designed for grease oil is a poor substitute. You haven't read much about this issue have you?

Poll, Condition of my IMS bearing
 

Considering the DOF fix uses oil to lubricate the bearing, I would think oil as a substitute is just fine

And my point was, the bearing destruction wouldn't progress very quickly if it had oil around it to lubricate it...

Hi, I think you are likely correct. I'm sort of expecting, and hoping my bearing will be no worse than yours. It's going to be interesting to find out.
I'm going to take some pics of the old bearing.

Cheers!

Hi, from the service history it looks like the car has only had 4 oil changes in it's life. The previous owner used 20K kilometres as his oil change limit, not the number of years. That's why it was a 4 year gap between the most recent oil changes. If the theories about leaving 'old' oil in the engine are correct then I might be in trouble :-)

On the PPI they did a compression test, not a leak down test as far as I know.
The compression test has 4 cylinders down 4% and 2 cylinders down 6% which isn't too bad I think.

Cheers.

Thanks for that, I'm keeping everything crossed!

One more factoid I forgot to mention, it's only ever had Mobil1 0w40 oil from new.

I know there are different opinions again on the best engine oil with some people going for higher viscosity. I know nothing about oil, but my hunch is that you'd be better off with lower viscosity in an IMS bearing with the grease washed out, assuming that the worst wear is happening on engine start up. Having said that, I don't think the longevity of the bearing is likely to be down to one thing. We'll probably never know.

Cheers!

Not bad as it really need to replace.

4 oil changes in 55k miles? That's well beyond the limit of a mass market oil like Mobil 1. I would get a sample of your oil after 4K miles and send to Blackstone Labs for one of those simple oil analysis. Then move to a more expensive oil like Motul Xcess 8100 or Joe Gibbs DT40 and use a spin on oil filter, which makes sure you're only using filtered oil at all times. Do a second oil analysis after a few oil changes. And make sure you let the egine warm up with a good 20 minutes of driving before you start laying into the higher RPMs. Best to take it easy until you have better sense of the impact of such long stints with old oil.
Or ignore all of the above and roll the dice. It's kind of like investing in stocks, some people sleep fine others check the computer every 5 minutes.

I don't know why the previous owner left it quite so long between oil changes, especially as he's a designer for a car company. I'm going to change the oil between services myself, and generally look after the engine as I intend to keep the car..
Assuming nothing serious is uncovered on Friday then I'll be reasonably confident about the engine going forward.

Who's doing the IMS work on your car Pominoz? I had the IMS Solution installed by Weltmeister Melbourne a year ago (04 986, single row bearing), and am happy that I did it.

Hi,

Weltmeister did my PPI actually, but I'm having the IMS retrofit done by Autoart in Preston. I had the major service done there are they seem very good, very friendly and helpful.
They should be using the new IMS pro dual row retrofit for single row bearings on my car, although they think there is a small chance my car may have the older dual row bearing in it. I'm not sure if that's likely given my car is 2002.

What condition was your old bearing in, and how may Kilometres had your car done?

My understanding is that a 2002 is likely to have the smaller single-row IMSB, but one can't be sure until things are dismantled. My car has done 77k kms. With the IMS solution it runs a bit quieter and I think smoother at idle, but I suppose that's subjective. The dual-row pro upgrade was not available when I had mine done, but I am not sorry I had the Solution kit installed. My old bearing looked OK, but had no grease in it at all, and did not spin as freely as I would have expected it to. If you search for my posts here you will see pictures of it that I posted at the time (a year ago). Good luck with it.

A lot.. Because as soon as an IMSB progresses to Stage III, chances of a long term retrofit without collateral damage is greatly reduced.

My dual row IMSB was still full of grease when I removed it at 53K miles last June. As I did a self-install I didn't send the old bearing in to LN for inspection (no warranty on self-installs).

That's pretty good, it fits in with the dual row IMSB being better than the single row. I'll be surprised if mine is as healthy as that.

Fingers crossed
 

So I've just dropped my car off to have the IMSB done. I'll be hearing fairly soon what condition the old IMSB is in, so I'm feeling a tiny bit nervous :-)
I'm getting the old bearing back, so I'll be putting some pictures up of it.
The only other question mark, is what condition my clutch is in. Could be an expensive day....

And the result is.....
 

Phew!

The old ISMB was still intact, even has the seals on but it looks like the grease has been washed out. The IMS was full of old oil. The old bearing turns smoothly by hand and there was no nasty stuff in the engine oil although it was a bit dirty even though it had just been changed. I guess the last change has acted as a flushing oil to help get rid of the remains of the 4 year old stuff that was in there before.

The clutch was down to 1mm of lining so that's been changed, and they've done the RMS as well. For anyone who is in Melbourne I can really recommend Autoart in Preston, they've done the whole job quickly and at a great price, so I can still afford some fuel for the car :-)

I guess it's up to you to decide who was most correct on the poll, but I'm very glad the one person who voted for near engine detonation was completely wrong :D

Finally some pictures of the old IMSB.

Cheers!



http://986forum.com/forums/uploads01...1411714881.jpg
http://986forum.com/forums/uploads01...1411714916.jpg

Sure, I understand a bearing progressing to other 'stages' of failure is BAD.

What I meant was, if the IMS gets oil, like the OPs was full of, why would it fail? Yes, the older the oil gets, the steeper the positive slope gets on the probability of failure curve, but hypothetically if the bearing gets some fresh oil now and then, how long would it be 'fine' in 'stage 2' failure?? Thats what I'm wondering..

That's a relief! Looks just like mine did. Now you have to get the Dremel out and cut it in half so we can see the insides.

Glad to see the bearing is in decent shape. When I pulled mine at 43k it was much like yours, seals intact but the grease washed out. Basiclly got it before the next failure stage were the real damage begins.

That means I'll have to buy a Dremel ��

I took it for a gentle run yesterday evening, and the engine seems noticeably quieter to me, mechanically. Did you find that?

Annoyingly though, I started getting a clunk from somewhere at the back over bigger bumps. Hopefully it's just something needing tightening. The engine mount was changed so it won't be that. Oh well.

I'm pretty pleased to see that it survived the 4 year old oil. I'm very glad I didn't wait to get it done.
The guy that did the work has obviously seen a few, and he says if you think your IMSB might be dying, then it's already too late.

My bearing was much the same as yours when it was taken out. It is a relief to not have the IMS worry, and I wonder if this is why the engine seems to run better? As for your rattle from the back over bumps, I had that too, which turned out to be the rear lower control arms. These seem to be a common problem, and they cost a bit but fortunately was done under warranty in my case. The OEM parts are expensive, but cheaper non-OEM arms are available on Ebay I think. Search this forum for more information, I believe you may be able to DIY.

I'll check out the rear lower control arms, thanks. I probably will have to DIY this if I can because I'm stretching my toy budget a bit with all this :-)

Log onto < designe911.com > and look under "suspension & axle" for your particular Boxster.

The suspension parts (made by TRW) are OEM and they ship to Oz same day. Prices are +/- half of what you pay here, delivery in a week....
I've been using them since 2009 without a hitch.

Hi, thanks for that, looks useful.

I got under the car today just to have look, and gently hit a few things with my trusty rubber hammer. It looks very clean underneath and the bushes I could see all look intact. The noise only seems to happen at about 40K over pretty bad surfaces. As this has only started since I got it back from having the IMSB done, my first stop will be to phone them in the morning and see what they say about it. Interestingly the car pulls slightly to the left now, and it didn't before I had the work done. Seems like something has moved.

Cheers.

I had a look under my car, the arms that were replaced were the 'trailing' arms, and from what I have read on this forum previously, they are the most likely to be the problem. When mine were replaced (under warranty) I was told the job was worth about $2K, which seemed high to me but that's what he said. It included rear suspension realignment. If you have a look at the Pelican Parts website, there are 'technical articles' that should help you, including DIY alignment.

Yes. I think if there is a problem, trailing arms will be it. There's some good stuff about how to replace them in some old posts here. It's going back in on Thursday and I'll see what they say, if it's trailing arms, and it's expensive, I'll have a go at doing it myself.

Thanks.

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