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986 value with bad engine


smit572

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Sorry to hear this :( 

Have always been of the opinion that a replacement IMSB is not necessarily a good thing, depending on how it's done, or who it's done by. Interesting response by Project Nine.

What will you be doing with the car?

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9 hours ago, K.I.T.T. said:

Sorry to hear this :( 

Have always been of the opinion that a replacement IMSB is not necessarily a good thing, depending on how it's done, or who it's done by. Interesting response by Project Nine.

What will you be doing with the car?

Just waiting on the final cost to repair before I make a decision , car is 986 facelift immaculate with 53,000 mile so initially thinking of repair

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13 minutes ago, Sanky said:

@smit572, just out of interest, what sort of mileage did the replacement bearing have?

My Spidey senses say 15k miles...

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45 minutes ago, K.I.T.T. said:

My Spidey senses say 15k miles...

Wow!  Cheap bearing, wrong bearing, bad installation or is the car parked pointing up or down a slope all the time allowing oil acid action on the bearing seal all the time.  This last factor seems to come up quite often with the cases of IMS failure in the US or could be a red herring as I know there are many in this issue.

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2 hours ago, ½cwt said:

Wow!  Cheap bearing, wrong bearing, bad installation or is the car parked pointing up or down a slope all the time allowing oil acid action on the bearing seal all the time.  This last factor seems to come up quite often with the cases of IMS failure in the US or could be a red herring as I know there are many in this issue.

Please could you elaborate on the oil acid action? Assume this is a non-issue on cars that are driven regularly?

Over the last year or so, have heard of a number of instances where replacement bearings have failed - some LN, others weren't specified. Not saying OE bearings don't fail, but don't recall hearing of any failing over the same period. And bad news travels fast. Opinions will differ on this, but am firmly in the "if it ain't broke, don't replace it" camp when it comes to the IMSB.

The outfit that replaced the OP's IMSB seem to have mixed reviews on Google.

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2 hours ago, K.I.T.T. said:

Please could you elaborate on the oil acid action? Assume this is a non-issue on cars that are driven regularly?

Over the last year or so, have heard of a number of instances where replacement bearings have failed - some LN, others weren't specified. Not saying OE bearings don't fail, but don't recall hearing of any failing over the same period. And bad news travels fast. Opinions will differ on this, but am firmly in the "if it ain't broke, don't replace it" camp when it comes to the IMSB.

The outfit that replaced the OP's IMSB seem to have mixed reviews on Google.

If the car is kept on a slope regularly it can leave part of the seal immersed in engine oil so as oil gets older in its normal drain cycles it gets more acidic and attacks the seal, the seal allows oil through the bearing into the hollow interior of the shaft, this oil continues to degrade with heat cycles and time and is it is never drained from the car when the engine oil is changed because it is trapped in the hollow shaft.  This increases the break down speed of the seals and the flushing of the grease from inside the bearing hastening its demise.

Not even contemplating an IMS change on mine unless it is possible to detect that it is needed, which seems not to be the case without getting almost as far as changing it anyway.  15K miles seems a very short life for a fitted for life bearing.

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1 hour ago, BTM520 said:

I am stunned to learn that replaced bearings fail. Nobody's going to go to them for an IMS bearing ever again. Spread the word. 

Why? The original is a bearing. Replacements are if the same or similar improved spec. Unfortunately for us, a changed IMS doesn't make for a bullet proof engine. You have to make a value judgement on the service history, the type of quality of bearing, the installation, any other data such as cam deviation. 

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I've read seven Boxster forums almost daily back to a time before the IMS was even known to be replaceable.   I haven't seen a lot of LN bearing failures reported compared to the number installed.  And in the UK, haven't many of the bearing replacements been OEM ones.   

A lot of the success of the swap has to do with the condition of the engine with the original bearing. Look at the pre-installation qualification portion of the LN instructions. How much debris was still floating around in the engine (and no a simple oil change doesn't clean it all out). Another variable is how true the alignment of the case openings for the crankshaft and the IMS shaft are to each other. And of course the tools the installer uses and their experience. Just fitting a bearing in is easy, doing it right is skill and patience and experience.

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On 3/24/2020 at 1:04 AM, mikefocke said:

I've read seven Boxster forums almost daily back to a time before the IMS was even known to be replaceable.   I haven't seen a lot of LN bearing failures reported compared to the number installed.  And in the UK, haven't many of the bearing replacements been OEM ones.   

A lot of the success of the swap has to do with the condition of the engine with the original bearing. Look at the pre-installation qualification portion of the LN instructions. How much debris was still floating around in the engine (and no a simple oil change doesn't clean it all out). Another variable is how true the alignment of the case openings for the crankshaft and the IMS shaft are to each other. And of course the tools the installer uses and their experience. Just fitting a bearing in is easy, doing it right is skill and patience and experience.

Which other forums do you suggest to read? As a new owner I,d like to read as much information as possible not just on this issue.

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9 minutes ago, Darren Sapsford said:

Which other forums do you suggest to read? As a new owner I,d like to read as much information as possible not just on this issue.

986forum.com is pretty much the US equivalent of this one and has a lot of info on it.  There are others useful resources like renntech.org, Pedro's Garage, and 101projects (and its sister site pelican parts) again US based.  Just run Google searches for any queries and you'll find more resources on forums and YouTube.

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  • 2 weeks later...

986forum, pedrosboard, renntech, rennlist, pelicanparts, babblers, BoXa.net, pistonheads, porscheforum.com.au, planet9 and any number of perhaps 20 sites referenced in posting on these over the last 20 years and found worth remembering.

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