Cylinder sleeves

[DVST8]

I was reading in Excellence magazine that in the 98/99 Boxster's they re-sleaved previously discarded casting due to the high demand for these cars, and that these sleeves were prone to failure

I found a '98 that had it's engine replaced about 5000km ago due to a sleave failure. How would I know if the replacement engine dosen't have this or another 'defect'? Is there a manufacture date stamped on it somewhere?

Does the fact that this car has had the engine replaced make it more, or less valuable?

Or should I be looking for 2000+ year Boxters?

[Tool Pants]

What month is the article as I am behind in my Excellence reading.

It has been said that sleeved engines were only on some model year 1999s, not 1998s. Cars made in late 1998 and early 1999. But there has been a lot of guessing over the years since Porsche will not release a list of the sleeved engines, or even acknowledge that it happened.

The sleeved engines usually failed early in their life. But since the Box is a second or third car you still see a current report once in a while. I have not heard of a replacement engine being sleeved. I think Porsche learned their lesson 7 years ago.

I don't think a replacement engine effects value. There were a lot of 986 Boxsters made, something like 160,000. Not a rare car. And a lot of engines have been replaced over the years.

http://www.pca.org/tech/tech_qa_question.asp?id={F3EA752A-E838-43E5-A43D-BB4F445F5A8F}

[MikenOH]

to the lack of blocks being produced by their supplier during that time frame of the '99' model year, I would not think there is much of a chance that the replacement block would be prone to the same type of failure. As tool pants said, Porsche learned from that experience--I hope.

[DVST8]

Originally Posted by Tool Pants

What month is the article as I am behind in my Excellence reading.

September 2006. The article starts on page 117.

[MNBoxster]

Hi,

The issue was not a lack of blocks. It was a production run of reject blocks, something like 3600 in total ('99 MY production was 22,063 units, so maybe 16.5% of all '99's were affected). Demand for the car was so high that Porsche chose to sleeve the substandard blocks to prevent interupting supply of '99 model year cars only, and they were distributed worldwide, not specifically to the US Market.

Most failed early in their life/mileage and had their engines replaced with standard non-sleeved engines.

The odds of coming across one today which has not been addressed is probably 1/10th the odds of having RMS failure. It simply isn't an issue which should concern you.

Excellence may have done a recent article, but they either found one of the few remaining cars (beating the odds as I said), or in a need to come up with a few column-inches resurrected the past. The Press and Hearsay have blown this all out of proportion.

I own a '99 and if buying another, I wouldn't even consider this issue at all...

Happy Motoring!... Jim'99

[Brucelee]

I think Jim's facts are accurate.

[DVST8]

Originally Posted by Brucelee

I think Jim's facts are accurate.

So what about the 98 that I'm looking at that that 'says' it had an engine replaced due to a sleeve failure? Sounds like this should have never been the case; anomaly?

[MNBoxster]

Originally Posted by DVST8

So what about the 98 that I'm looking at that that 'says' it had an engine replaced due to a sleeve failure? Sounds like this should have never been the case; anomaly?

Hi,

I think you're confusing twp separate issues. There were issues with sleeved engines in the '99 model year as described here, but the '98s were unaffected.

Some '97s and '98s suffered engine failures from issues with the Cylinder Lining (Locasil), not Liners. You can't have a raw alloy cylinder because it's too soft to withstand any apreciable wear. The cylinder must be lined with a much harder substance such as a ceramic.

Check out this thread - http://www.986forum.com/forums/showthread.php?p=37846#post37846 and maybe it'll shed a little more light. Again, if the engine has already been replaced (especially if it has racked up a few miles since), it's a non-issue. Hope this helps...

Happy Motoring!... Jim'99

[Brucelee]

BTW-That sleeve issue is something that Porsche should be duly ashamed of.

The Nykosill issue impacted BMW as well.

[DVST8]

Thanks guys. This really cleared things up for me.

[MikenOH]

Where did you get the 3600 figure for the number of sleeved blocks?

I ask since the window on these blocks is usually noted as 10-98 through 2-99. If they were building roughly 1900 cars/month and the problem with the supplier ran 4-5 months, the number would seem to be a lot higher. Or were they building cars with both good quality blocks and sleeved blocks at the same time?

[MNBoxster]

Originally Posted by MikenOH

Where did you get the 3600 figure for the number of sleeved blocks?

I ask since the window on these blocks is usually noted as 10-98 through 2-99. If they were building roughly 1900 cars/month and the problem with the supplier ran 4-5 months, the number would seem to be a lot higher. Or were they building cars with both good quality blocks and sleeved blocks at the same time?

Hi,

On inquiring, I was told this at a PCA Tech session by a Guest Speaker from Porsche AG.

And yes, it was only a portion of the blocks produced during this period which failed Quality Inspection.

Because the M96 Block was shared by the 996 also, (it is now shared by the 997, 987 and Cayman), Porsche made the decision to use only A grade blocks for the 996 (makes sense since they're double the cost) and to repair the reject blocks (by post-cast machining and inserting sleeves) for the Boxster. He further said that there were no records as to how many of these stayed in Stuttgart and how many were shipped to Valmet in Uusikaupunki, though some were shipped to each. Hope this helps...

Happy Motoring!... Jim'99

[MikenOH]

Quote:
"Because the M96 Block was shared by the 996 also, (it is now shared by the 997, 987 and Cayman), Porsche made the decision to use only A grade blocks for the 996 (makes sense since they're double the cost) and to repair the reject blocks (by post-cast machining and inserting sleeves) for the Boxster. He further said that there were no records as to how many of these stayed in Stuttgart and how many were shipped to Valmet in Uusikaupunki, though some were shipped to each. Hope this helps...:

originally posted by MNBoxster


So, they knew they didn't want to put those blocks in a 3.4L 996 which sold for roughly $75K+ but they were OK for the 2.5L 986 selling for $45K+. Wonder if they thought 996 owners would be more outraged at Porsche using reject blocks in a 996 than 986 owners might be or if the additional HP and torque of the 3.4L motor would be more prone to make those motors fail?

Either way it stinks. If it was a good idea and they really didn't expect a reliability problem, it should have worked in either car. If they thought there might be a reliability issue, then it shouldn't have been done.

The comment about the lack of records on where they went seems like a odd. As anal as Germans can be at times on details--I'm married to one--and the fact that each of these motors required a lot more labor in production than the unsleeved block, you would think they'd know exactly which motor was sleeved, which wasn't and where it went.
Then again, maybe they didn't want to know.....

Interesting story though; thanks for sharing it.

[Brucelee]

I found the lack of records hard to believe also.

[MNBoxster]

Originally Posted by MikenOH

Quote:
"...Then again, maybe they didn't want to know...

Hi,

Exactly...

Happy Motoring!... Jim'99