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Dual Row IMS Failure at 58,000 miles


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Just a word to the wise; I have a 2000 Boxster S USA that started leaking oil a few months ago. I finally got around to taking it in to have it looked at and it turned out that my IMS bearing was failing. I didn't have "chunks" of metal in the oil, but there was what appeared to be glitter in the oil filter. It doesn't appear that the motor is ruined--yet. But you never know. I opted to go ahead with the LN Retrofit and my mechanic ran the car and drained the oil 3 times (until no metal was evident) and I'm going to drain it again this weekend and check it (he also installed a magnetic drain plug). The bearing was still together albeit a bit wobbly. I wouldn't have gone much further before my car became a boat anchor.

Bottom line, don't screw around with an oil drip hoping it's just the Rear Main Seal; I gambled (or screwed around) and nearly lost. This was a dual row bearing, which may have saved my car, but they they fail, too.

I have attached a picture of the bearing, on which can be seen a paste of metallic bits.post-15474-0-44902000-1393055344_thumb.j

Also shown is the IMS tube, which escaped damage as the bearing had not completely failed. post-15474-0-90024600-1393055353_thumb.j

My mechanic and I felt the risk of repair was worth taking (although I signed a waiver acknowledging that I knew the new LN bearing could also fail due to the metal in the oil system), because $3800 beats paying God-knows-what for a new motor for a 15 year old car. (The price included a new clutch and rear CV joint rebuild among other things.)

Be proactive, and if you're looking to buy an M96-97 motored vehicle, just add $3000 to the purchase price.

Devin

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Yes, I would say that bearing is completely toast. I would be curious how much metallic debris you find the next time(s) you drain the motor. With the bearing that far gone, that means a lot of metal was in there -- I'm surprised that he was able to flush it out with just 3 drains.

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The difference in metallic debris between the second and third flushes was huge (the third filter looked like fresh oil), but he told me that at one of the classes he attended they said that 7 or 8 flushes would be optimal (even though LN doesn't publicly recommend retrofitting an engine with ANY metal debris). I'm just going to keep doing it until its pristine, assuming it lasts long enough. I'll be out $50 in oil and whatever a filter costs each time, but that still beats the cost of a new engine. I can only hope for the best, I suppose.

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Ya, I know it's not recommended when you have had metal debris like that. A lot of knowledgeable folks would say the textbook next move at that point is a complete rebuild of the engine -- that flushing it won't be possible. But I have read posts similar to yours where people tried to flush the engine and it seemed to work (either that or they never followed-up on their post after the fact). I'm also not sure how much debris those people had, but that pic of your IMS is shocking -- there's nothing left but a metallic paste.

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Ya, I know it's not recommended when you have had metal debris like that. A lot of knowledgeable folks would say the textbook next move at that point is a complete rebuild of the engine -- that flushing it won't be possible. But I have read posts similar to yours where people tried to flush the engine and it seemed to work (either that or they never followed-up on their post after the fact). I'm also not sure how much debris those people had, but that pic of your IMS is shocking -- there's nothing left but a metallic paste.

Continuing to run and engine with a prior failed IMS is a total crap shoot, some make it, but many do not. The M96/97 engine design has a lot of small "pockets" in the oil system where debris can lurk for a long time before breaking loose and circulating through the system; and it only takes one particle in the wrong place to start a cascading disaster scenario. Your best bet is lots of oil & filter changes (you can use non synthetic oil for this, and a spin on filter, magnetic drain plug, and magnetic pad wrapped around the filter would be advisable as well). Good luck........

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Thanks JFP,

That's my plan at this point.

Silver, the bearing was still together with all the balls still working, but they were a bit scratchy.

The picture of the sludge on the bearing is what collected on the outside of the seal.

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That makes more sense. Yes, I definitely would have expected the bearings to be at least pitted, so no surprise there.

I know I speak for both myself and JFP in wishing you the best of luck. Keep your eye on the oil and maybe you catch a lucky break. I would be very curious to know how this goes so let us know how it goes in the future as you put some mileage it. All the best.

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Ya, I know it's not recommended when you have had metal debris like that. A lot of knowledgeable folks would say the textbook next move at that point is a complete rebuild of the engine -- that flushing it won't be possible. But I have read posts similar to yours where people tried to flush the engine and it seemed to work (either that or they never followed-up on their post after the fact). I'm also not sure how much debris those people had, but that pic of your IMS is shocking -- there's nothing left but a metallic paste.

Continuing to run and engine with a prior failed IMS is a total crap shoot, some make it, but many do not. The M96/97 engine design has a lot of small "pockets" in the oil system where debris can lurk for a long time before breaking loose and circulating through the system; and it only takes one particle in the wrong place to start a cascading disaster scenario. Your best bet is lots of oil & filter changes (you can use non synthetic oil for this, and a spin on filter, magnetic drain plug, and magnetic pad wrapped around the filter would be advisable as well). Good luck........

JFP,

I have a magnetic drain plug, but what are my options for a spin-on filter? Would that require the LN spin-on adapter? Also, I've never heard of the magnetic wrap. Where would I source that? Thanks,

Devin

PS: My condolences to your brother; I was a divorce attorney many moons ago... :)

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Ya, I know it's not recommended when you have had metal debris like that. A lot of knowledgeable folks would say the textbook next move at that point is a complete rebuild of the engine -- that flushing it won't be possible. But I have read posts similar to yours where people tried to flush the engine and it seemed to work (either that or they never followed-up on their post after the fact). I'm also not sure how much debris those people had, but that pic of your IMS is shocking -- there's nothing left but a metallic paste.

Continuing to run and engine with a prior failed IMS is a total crap shoot, some make it, but many do not. The M96/97 engine design has a lot of small "pockets" in the oil system where debris can lurk for a long time before breaking loose and circulating through the system; and it only takes one particle in the wrong place to start a cascading disaster scenario. Your best bet is lots of oil & filter changes (you can use non synthetic oil for this, and a spin on filter, magnetic drain plug, and magnetic pad wrapped around the filter would be advisable as well). Good luck........

JFP,

I have a magnetic drain plug, but what are my options for a spin-on filter? Would that require the LN spin-on adapter? Also, I've never heard of the magnetic wrap. Where would I source that? Thanks,

Devin

PS: My condolences to your brother; I was a divorce attorney many moons ago... :)

Yes, you would want the LN adaptor and one of the appropriately sized filter mag panels.

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Changed the oil today; didn't see any metal on the magnetic drain plug or on the filter (at least with the naked eye). I'm going to drive it a couple hundred miles and change it again and see what it looks like. It has now been changed 4 times.

post-15474-0-32323500-1393199789_thumb.j

Devin

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  • 2 weeks later...

Thanks, txhokie4life, I just did my 6th oil change and installed LN Engineering's Spin-On-Filter Adapter; no more bypassing of oil. No particles found on the mag plug and nothing in the filter. I think I'll do one more change in a couple hundred miles and then declare victory. The thing is either going to grenade on me or not. I think I've done all I can.

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This may be a dumb question, but....

Why would a failing IMSB cause an oil leak at the IMS flange? It's not as though there's pressurized oil there - more's the pity. Does the IMSB start vibrating which causes the flange seal to leak?

Sometimes when the IMS starts to beat itself to death, one of two things can happen that will cause oil leaks. There is a seal on the IMS bearing center bolt that fails, allowing oil to leak out. In extreme cases, the center bolt can even fail completely, allowing the nut with part of the center bolt to actually fall off and drop to the bottom of the bell housing, which will also allow the oil to leak out:

failedIMScenterbolt_zps3d499b66.jpg

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That's an interesting photo. What's holding the toothed starter ring - is that for an auto tranny car?

My question is whether you can see enough of the IMS flange, with the flywheel still attached, to determine whether it's a single row or double row IMS bearing. From your photo it would appear the answer is "yes".

I'm convinced that there's no way to tell without pulling the tranny whether my 2000 986 has the double row IMSB (most likely) or a single row IMSB (random chance). I can't even order parts until I get that far. But if I can just pull the tranny back a few inches and shine a flashlight up there, could I see which IMSB I have? I.e. shallow or deep-dish IMS flange.

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That's an interesting photo. What's holding the toothed starter ring - is that for an auto tranny car?

My question is whether you can see enough of the IMS flange, with the flywheel still attached, to determine whether it's a single row or double row IMS bearing. From your photo it would appear the answer is "yes".

I'm convinced that there's no way to tell without pulling the tranny whether my 2000 986 has the double row IMSB (most likely) or a single row IMSB (random chance). I can't even order parts until I get that far. But if I can just pull the tranny back a few inches and shine a flashlight up there, could I see which IMSB I have? I.e. shallow or deep-dish IMS flange.

The photo is from a Tip equipped car, which many internet resources will continue to tell you do not have IMS failures.

No, you cannot see the IMS flange on a manual equipped car without removing the flywheel; there just isn't any room. On a Tip car, you can see the flange through the flex plate, but even then you are only a few bolts away from an unobstructed view.

When we do a 2000-2001 car, we pull it apart and then look to see which style is in there. LN stopped allowing exchange returns due to the number of people that ordered the wrong style bearing based upon build dates, VIN numbers, or whatever other methods they found on the internet; all of which proved to be useless. There is simply no other way to do this, except by looking at the flange with the flywheel removed.

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