Are replacement 997 engines less likely to bore score?
Discussion
I've recently bought a 2005 911 997 C2 with FPSH.
The car has done 89k miles but 16k (Feb 15) ago had a new factory supplied & OPC fitted short block due to bore scoring in cylinders 5 &6. Whilst in there the clutch, flywheel & loads of other bits were done, resulting in a bill for the previous owner of 14.7k.

As this was 10 years after the model launch, is it likely that Porsche improved the internals of replacement engines, or might it still be susceptible to bore scoring in the future?
Thanks in advance.
It has an upgraded IMS bearing compared to 2005 original - that we know of - but who really knows what else was done to lining tech etc? I have not heard of replacement scoring again on here but that does not mean it hasn't happened. My wife's 2005 S scored at just 7500 miles. She has since done 80 k with replacement engine and subsequent 2008 997.1 C4s with no scoring issues. Great cars IMO. If this one lets go it will go to Hartech. Definite keeper.
Edited by drmark on Saturday 29th October 14:20
Sunnysider said:
As this was 10 years after the model launch, is it likely that Porsche improved the internals of replacement engines, or might it still be susceptible to bore scoring in the future?
Thanks in advance.
Unfortunately no.Thanks in advance.
The replacement engines were all built on the line when the model was current then stored, as such they will be just as prone as all the others.
Thanks for the info chaps, although it's slightly depressing to learn that Porsche didn't attempt to put right the scoring issue on replacement engines.
Still, life's too short to worry about an engine going pop, so I'm going to drive the snot out of the car & if it breaks, just get it fixed.
Edited by Sunnysider on Friday 28th October 09:48
Sunnysider said:
Thanks for the info chaps, although it's slightly depressing to learn that Porsche didn't attempt to put right the scoring issue on replacement engines.
Still, life's too short to worry about an engine going pop, so I'm going to drive the snot out of the car & if it breaks, just get it fixed.
Just don't lug the engine, the engine is made to rev, so don't be scared of it.Still, life's too short to worry about an engine going pop, so I'm going to drive the snot out of the car & if it breaks, just get it fixed.
Edited by Sunnysider on Friday 28th October 09:48
lugging is the bore score killer.
Just drive the , and don't worry about the engine , more cars are out there with out any problems than the few that do.
Every manufacture has problems, you just don't here about them unless you have one of there cars and trawl through forums.
Its about time Porsche owners stopped moaning and making a big thing over an issue that affects very few cars, they are only hurting there re-sale value in the long run.
I know it hurts if it happens to your car but it is not common.
Every manufacture has problems, you just don't here about them unless you have one of there cars and trawl through forums.
Its about time Porsche owners stopped moaning and making a big thing over an issue that affects very few cars, they are only hurting there re-sale value in the long run.
I know it hurts if it happens to your car but it is not common.
Porsche911R said:
Just don't lug the engine, the engine is made to rev, so don't be scared of it.
lugging is the bore score killer.
What does lugging mean?lugging is the bore score killer.
As a 997.1 owner of a 2007 car, I worry a little about bore scoring and IMS and generally big bills. But as mentioned, I drive the car in a way I enjoy it and will fix it if it breaks. But would want to minimise the possibility of it breaking. Hence asking what lugging means
Sunnysider said:
As this was 10 years after the model launch, is it likely that Porsche improved the internals of replacement engines, or might it still be susceptible to bore scoring in the future?
Even if they did not, the replacement engine(Porsche original) is quite fresh so I would just enjoy the car. To be honest, with today's 997 gen1 prices are so low, I would not worry too much about it.These few replies seem to me to clarify the situation and vindicate our usual comments - that basically they are great cars - that there is a variation in quality of the bore material, that some fail early and others last for ages and anyway only a small number fail prematurely and to avoid high torque or large throttle openings at low revs.
Since having plastic coated pistons we think the bore material also changed to Lokasil 2 which we think makes a stronger cylinder (hence very few cracking) but can have larger silicon particles so if they do come lose are more likely to score or wear out the piston coating.
I know already you will all take this next comment with suspicion but we have found that some of the bottom ends replacements we have dealt with have not been to the same standard (actually we have had a few problems with them) as new whole engines we inspected several years ago - although I guess if they were fitted by a main agent they would cover any subsequent failures. The situation is not as happy for the independent network if they experience similar problems.
Still very few fail and they are brilliant cars and I agree at very good prices for the product and risk. Anyway a re-fresh of the engine for such a car after over a decade is not unreasonable - especially as you can get some reliable cover against the cost from the Main agents, us and some others.
Baz
Since having plastic coated pistons we think the bore material also changed to Lokasil 2 which we think makes a stronger cylinder (hence very few cracking) but can have larger silicon particles so if they do come lose are more likely to score or wear out the piston coating.
I know already you will all take this next comment with suspicion but we have found that some of the bottom ends replacements we have dealt with have not been to the same standard (actually we have had a few problems with them) as new whole engines we inspected several years ago - although I guess if they were fitted by a main agent they would cover any subsequent failures. The situation is not as happy for the independent network if they experience similar problems.
Still very few fail and they are brilliant cars and I agree at very good prices for the product and risk. Anyway a re-fresh of the engine for such a car after over a decade is not unreasonable - especially as you can get some reliable cover against the cost from the Main agents, us and some others.
Baz
hartech said:
Anyway a re-fresh of the engine for such a car after over a decade is not unreasonable
Just a mild £12k refresh after 10 years. I'm glad that you have developed such intimate knowledge of the cars, it's very helpful, however the fact that you had to, and the scale of your organisation, is testament to their failure rate. Many performance models have problems but very few have such a ruinous cloud hanging over them in terms of repair cost to vehicle value ratio. The last two times I discussed this issue with dealers who sell these cars, they pinned failure rate at 20% and 30% based on what they sell it's actually an utter disgrace. I have more confidence in the reliability of my Maserati than my former 997.
Yes Jake - a lot of dealers got caught out a few years ago when the public started to get their cars tested to see if they have bore scoring (even though they had few or no symptoms by then) and when they found they did - they neatly disposed of them in the trade so they had no personal comeback. The result was a number of dealers innocently selling the cars on only for the new owner to have them tested and comeback for a contribution to the rebuild on the grounds that it was sold not fit for purpose. The dealers had no comeback to the original seller to them as the dealer is regarded as the expert not the member of the public - as a result many refused to buy the models in, others had them tested first and this tended to lower the values for a while as owners struggled to dispose of them.
I do think however that this resulted in a higher proportion of cars with scored bores coming to the used car market for a while - so it might have been 20 or 30% offered to dealers but perhaps more like 15% with scores.
Since then of the dealers that inspect the cars before buying many say 1 or 2 in 5 have scores - but then again the public are more likely to offer them if they have seen a smoky black near exhaust (for example) or have experienced higher than normal oil consumption which the dealer cannot check out.
I don't think we would have risked the huge investment we put into this part of our business if it were not for the extremely happy coincidence that I first manufactured alloy cylinders and liners with Nikasil plating some 45 years ago and learned so much about the technical issues related to making the machining tolerances and fits right that I already was confident our solution would be extremely reliable. It also didn't take much detective work to see the connection between the thickness of the free standing alloy cylinder and creep ovality, the change to plastic coated pistons and scoring and various other clues that encouraged us to go with our belief that enough would fail to justify investment and proper organisation.
If we had been wrong we would have wasted a lot of time and money but because our guess proved right - it has paid of for us and our customers - but proportionally high investment in one area for small businesses is a risk - we knew it and took it - but I don't think we would have done but for that coincidence and previous familiarity with setting up a small engineering manufacturing base to make engine parts.
Having also been involved in larger scale volume manufacturing in the automotive and aerospace industries - I also sympathise with Porsche for the problems they experienced. We all enjoy the leading edge products they provide us with the chance to own and drive and they have always pushed technology ahead. They had to reduce the manufacturing cost from the very old fashioned production designs of the air cooled 9111 and 944/968 variants and knew why they needed alloy cylinders to allow big pistons to expand and contract with the cylinder bores in the difficult balance of a road car that can be driven as fast as a racing car in some circumstances.
The Lokasil idea was sound - the lack of support at the top may have reflected a general lack of understanding about composite creep (that afflicted all "metal" engineers at the time) and the change to plastic coated pistons seemed a solution. Then - when in time it shows up an engine weakness - there is no time for a manufacturer to sort it out as they are already designing, testing and building newer models.
In a way I think we have done a good service to Porsche by providing a quality service to help out afflicted owners and cars at a modest cost compared to their new replacement especially as all the causes we declared over 10 years ago were proven accurate and our solutions provided before the Gen 2 was know about incorporated all of the same changes.
Baz
I do think however that this resulted in a higher proportion of cars with scored bores coming to the used car market for a while - so it might have been 20 or 30% offered to dealers but perhaps more like 15% with scores.
Since then of the dealers that inspect the cars before buying many say 1 or 2 in 5 have scores - but then again the public are more likely to offer them if they have seen a smoky black near exhaust (for example) or have experienced higher than normal oil consumption which the dealer cannot check out.
I don't think we would have risked the huge investment we put into this part of our business if it were not for the extremely happy coincidence that I first manufactured alloy cylinders and liners with Nikasil plating some 45 years ago and learned so much about the technical issues related to making the machining tolerances and fits right that I already was confident our solution would be extremely reliable. It also didn't take much detective work to see the connection between the thickness of the free standing alloy cylinder and creep ovality, the change to plastic coated pistons and scoring and various other clues that encouraged us to go with our belief that enough would fail to justify investment and proper organisation.
If we had been wrong we would have wasted a lot of time and money but because our guess proved right - it has paid of for us and our customers - but proportionally high investment in one area for small businesses is a risk - we knew it and took it - but I don't think we would have done but for that coincidence and previous familiarity with setting up a small engineering manufacturing base to make engine parts.
Having also been involved in larger scale volume manufacturing in the automotive and aerospace industries - I also sympathise with Porsche for the problems they experienced. We all enjoy the leading edge products they provide us with the chance to own and drive and they have always pushed technology ahead. They had to reduce the manufacturing cost from the very old fashioned production designs of the air cooled 9111 and 944/968 variants and knew why they needed alloy cylinders to allow big pistons to expand and contract with the cylinder bores in the difficult balance of a road car that can be driven as fast as a racing car in some circumstances.
The Lokasil idea was sound - the lack of support at the top may have reflected a general lack of understanding about composite creep (that afflicted all "metal" engineers at the time) and the change to plastic coated pistons seemed a solution. Then - when in time it shows up an engine weakness - there is no time for a manufacturer to sort it out as they are already designing, testing and building newer models.
In a way I think we have done a good service to Porsche by providing a quality service to help out afflicted owners and cars at a modest cost compared to their new replacement especially as all the causes we declared over 10 years ago were proven accurate and our solutions provided before the Gen 2 was know about incorporated all of the same changes.
Baz
hartech said:
Stuff
Baz
Hi Baz,Baz
I'd appreciate your advice.
I've just bought a 997 Gen 1 ... 2005 model year and it's done 57k miles. Its had a bore scope inspection at Zentrum 1000 miles ago, and they confirmed that there was no scoring at that time.
So assuming they're right, what else can I do (aside from the full throttle at low revs thing mentioned above) to protect it. More frequent oil changes? Different oil?
Thanks,
J.
(tongue in cheek) Keep it as a garage queen.
If its a tip, knock it down to first when moving off rather than having it in 2nd as the box chooses.
Keep in mind high coolant speeds when using full power - i.e. don't go from idle to full bore standing start. Coolant speed is low at idle, if you go to full power instantly then the coolant won't have caught up yet and the bore can overheat in spots and cause material to come adrift.
All engines will wear, and eventually wear out. Just drive it and enjoy it, then if it does go pop at least you've had some fun. It could go pop while molly coddling it.
If its a tip, knock it down to first when moving off rather than having it in 2nd as the box chooses.
Keep in mind high coolant speeds when using full power - i.e. don't go from idle to full bore standing start. Coolant speed is low at idle, if you go to full power instantly then the coolant won't have caught up yet and the bore can overheat in spots and cause material to come adrift.
All engines will wear, and eventually wear out. Just drive it and enjoy it, then if it does go pop at least you've had some fun. It could go pop while molly coddling it.
Sunnysider said:
I've recently bought a 2005 911 997 C2 with FPSH.
The car has done 89k miles but 16k (Feb 15) ago had a new factory supplied & OPC fitted short block due to bore scoring in cylinders 5 &6. Whilst in there the clutch, flywheel & loads of other bits were done, resulting in a bill for the previous owner of 14.7k.
As this was 10 years after the model launch, is it likely that Porsche improved the internals of replacement engines, or might it still be susceptible to bore scoring in the future?
Thanks in advance.
Hi Sunnysider. Thinking of selling my 997 c2s with recent engine replacement from main dealer, just wondering how much you bought your model for in 2016 as can't see any examples on the current market? Thanks WThe car has done 89k miles but 16k (Feb 15) ago had a new factory supplied & OPC fitted short block due to bore scoring in cylinders 5 &6. Whilst in there the clutch, flywheel & loads of other bits were done, resulting in a bill for the previous owner of 14.7k.

As this was 10 years after the model launch, is it likely that Porsche improved the internals of replacement engines, or might it still be susceptible to bore scoring in the future?
Thanks in advance.
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