Early signs of bore scoring- what happened after? - Page 2 - 911/Carrera GT - PistonHeads UK

On a borescope my friend's car (he is in his early 70s and not really an internet user) has signs of early scoring in cylinder 6. Its a 997.1 C2S. He had asked for it to be checked during a plug change. Running well, needing no oil top ups between changes (approx 3000 miles). No external signs etc. Has anyone had a car like this that has run well long term and not had things progress? Or when scoring starts is progression a certainty? Thanks

I dont have an answer to your friends findings however if faced with the same situation I’d just run it till the oil usage becomes untenable. If he’s only doing 3000-5000 miles a year that could be a long time. Perhaps consider oil analysis and changing more frequently so any debris removed sooner. The other thing to do is take advice from a good independant specialist - having read lots of IMS horror stories I spoke to my indy (GCR central) who said if there are no signs of a problem leave well alone. As it happens, when fixing an oil leak he found mine had more play than was acceptable so it was changed.

bluetigerandy said: when scoring starts is progression a certainty Yes It will get worse

Well, mine went from brand new engine to being replaced under new car warranty due to excess oil consumption and sooting within 7500 miles and 18 months of leaving the factory. Scoring in 5 and 6. My second one was picked up at 65k during a pre-emptive conversion to 4.1 so no idea how long that would have gone on.

The internet scare stories are real I'm afraid. These engines are one of the most delicate ever produced and sadly the bore-scoring is likely to get worse. On the positive side, given the fella doesn't do many miles, it'll either a) be long gone and someone elses problem or b) not manifest into catastrophic failure for a few years yet

The sensible thing to do would be sell it now. Ideally px it or We Buy Any Car. I have no idea how a dealer would value a car like this without a thorough inspection for bore score. Maybe if he really is 70 then it's an advantage as no one would assume the old boy is pulling a fast one.

Does bore score manifest as progressively more oil consumption, or does it go from no signs to catastrophic failure? I guess OP if the answer to this is progressive, I would live with it doing only small miles per year and know I would have opportunity to address it if oil consumption became high.

When the dreaded bore scored I bit the bullet and had a rebuild. At the end of the day i have a great car which is future proofed. I much prefer it to my 991 and it cost the same as a 3 year old Kia hatchback to fix. Should see me out now. people pay 40 grand for a hot golf and swallow 15k in depreciation without moaning.

If bore score doesn’t result in catastrophic failure which I don’t believe it does, the OPs mate has the option to keep driving and enjoying the car until it either starts using oil and becomes annoying, or starts making a ticking noise that impairs the enjoyment of the car, both of which may not happen while he owns it. At my age and expected ownership length I’d get it rebuilt by Hartech but that’s not necessarily the right decision for everyone’s circumstances.

My 987.1 Cayman S. Went from needing 1 litre oil once every 6000 miles to needing 1 litre very 300 miles in 6 months and 7000 miles useage.

magic Monkey Dust said: When the dreaded bore scored I bit the bullet and had a rebuild. At the end of the day i have a great car which is future proofed. I much prefer it to my 991 and it cost the same as a 3 year old Kia hatchback to fix. Should see me out now. people pay 40 grand for a hot golf and swallow 15k in depreciation without moaning. Exactly what I did - along with an oversize to 4.1, new cats, exhaust, engine mounts, oil cooler, water and oil pump, suspension, coolant pipes etc etc. Cost me a fortune but we love the car. It was always going to be a keeper and, 16 years in, it now drives like new.

anonymous said: [redacted] So are DFI / 997.2 engines now thought to be vulnerable to bore score? And how come they’re more expensive to fix / rebuild than 997.1 engines?

bluetigerandy said: On a borescope my friend's car (he is in his early 70s and not really an internet user) has signs of early scoring in cylinder 6. Its a 997.1 C2S. He had asked for it to be checked during a plug change. Running well, needing no oil top ups between changes (approx 3000 miles). No external signs etc. Has anyone had a car like this that has run well long term and not had things progress? Or when scoring starts is progression a certainty? Thanks I’ve done a borescope inspection on a 2008 Cayman 987 S 3.4. Minor score marks on cylinder 6. 6,000 miles and 12 months later and did another inspection. Compared images and it wasn’t noticeably worse. Oil consumption was below the normal stated value in the handbook, and there was no evidence of engine noise or piston slap at hot idle. I did an oil analysis both times, and metal content was just above the maximum threshold

IREvans said: I’ve done a borescope inspection on a 2008 Cayman 987 S 3.4. Minor score marks on cylinder 6. 6,000 miles and 12 months later and did another inspection. Compared images and it wasn’t noticeably worse. Oil consumption was below the normal stated value in the handbook, and there was no evidence of engine noise or piston slap at hot idle. I did an oil analysis both times, and metal content was just above the maximum threshold Some really helpful replies here so thank you everyone- but especially IREvans- I think this is exactly the sort of experience he was looking for. Please keep the thoughts coming.

anonymous said: [redacted] 9A1 failure rate is a tiny fraction of M97 failure rate. Not remotely comparable. People forget that the early 9x7.2 cars are now nearly 15 years old (first 997.2 were late 2008). With 9x7.1 cars, they were chucking in new engines at scale under warranty from the get go. When you have Hartech having to post online repeatedly because they can't find a borked one to do their development work, you know they aren't going pop with much frequency: http://www.911uk.com/viewtopic.php?p=1644727 For the OP, think it's fair to say scoring can progress at different rates. Some can go 10s of thousands of miles slow getting worse, others can go from first signs of increasing oil consumption to knacker in well under 10k miles. I think anecdotally it seems like the ones that fail at lower miles are the ones that fail fast.

johnny senna said: And how come they’re more expensive to fix / rebuild than 997.1 engines? Because no one is doing it. With the m97 (from the 9x7 cars) there is a larger network of shops rebuilding these and using various different replacement liners which are of course being manufactured by another network of manufacturers. With the newer engine this network does not exist as it is either not required or not required yet.

in the video's they speak of, watch out for to rich fuel (to much or how you say that) = wash away oil film wrong cheap fuel = not good, only 98+ best stuf use! many 'porsche' drivers seem to use the cheaper or 95+ octane or lower? or bio fuel, just stop that! lol, thats bad! and you are fooling yourself, cheap = using more fuel and more damage to your engine = way more expensive then you think you can save. and use good engine oil, so you can use a second hand Porsche from say 4 other owners each choosing their own fuel, maybe the first one asked the dealer, or looked in the book, yes you can use bio added fuel... or Ron92/95? or with 10% bio? and used that for years, by the time another Porsche lover buys such Porsche it can already have the first signs, or just not... so best to use proper fuel, only the best and make sure the engine is properly adjusted, not running too rich, to avoid bore wash. so you can postpone the major damage, some can drive many more miles with the right treatment I guess.

GTRene said: in the video's they speak of, watch out for to rich fuel (to much or how you say that) = wash away oil film wrong cheap fuel = not good, only 98+ best stuf use! many 'porsche' drivers seem to use the cheaper or 95+ octane or lower? or bio fuel, just stop that! lol, thats bad! and you are fooling yourself, cheap = using more fuel and more damage to your engine = way more expensive then you think you can save. and use good engine oil, so you can use a second hand Porsche from say 4 other owners each choosing their own fuel, maybe the first one asked the dealer, or looked in the book, yes you can use bio added fuel... or Ron92/95? or with 10% bio? and used that for years, by the time another Porsche lover buys such Porsche it can already have the first signs, or just not... so best to use proper fuel, only the best and make sure the engine is properly adjusted, not running too rich, to avoid bore wash. so you can postpone the major damage, some can drive many more miles with the right treatment I guess. Both may help. But it's a design / manufacturing flaw. Our first 997 was still on its factory oil, was only filled up with good fuel and run in and driven carefully and it needed a new engine at 7,500 miles.

GTRene said: in the video's they speak of, watch out for to rich fuel (to much or how you say that) = wash away oil film wrong cheap fuel = not good, only 98+ best stuf use! many 'porsche' drivers seem to use the cheaper or 95+ octane or lower? or bio fuel, just stop that! lol, thats bad! and you are fooling yourself, cheap = using more fuel and more damage to your engine = way more expensive then you think you can save. and use good engine oil, so you can use a second hand Porsche from say 4 other owners each choosing their own fuel, maybe the first one asked the dealer, or looked in the book, yes you can use bio added fuel... or Ron92/95? or with 10% bio? and used that for years, by the time another Porsche lover buys such Porsche it can already have the first signs, or just not... so best to use proper fuel, only the best and make sure the engine is properly adjusted, not running too rich, to avoid bore wash. so you can postpone the major damage, some can drive many more miles with the right treatment I guess. It’s a mechanical issue, and different fuel or engine oil will make next to no difference. The bore scoring will first occur when the oil film breaks down in the hottest cylinder, some believe after a heat soak event.

He's not used anything other than Shell V power and the oil is Mobil as recommended by Porsche (serviced at well respected indys). I suspect it's short journeys that have contributed to an oil film breakdown.

The difficulty that your friend now has is that now he knows. He knows that his car is afflicted with one of the most expensive, ruinous issues that these .1 cars have. Ignorance is bliss as the saying goes but now he can no longer feign ignorance of the car’s issues. That is why it was a mistake to be persuaded into a borescope during the spark plug change. What to do? He really only has one choice - save the pennies and get the engine rebuilt. Trying to sell the car as is will hit him in the wallet. Lying or trying to hide the issue is not what one would expect for an elderly gentleman, anyone even, so he’s stuck with it. This is what the repair industry want to happen - they want folk to borescope their cars, at PPI, service or whenever because they know that once you know you have to fix it. Good luck and try and get the work done before inflation makes it even more difficult to contemplate.

bluetigerandy said: He's not used anything other than Shell V power and the oil is Mobil as recommended by Porsche (serviced at well respected indys). I suspect it's short journeys that have contributed to an oil film breakdown. Yes, an oil film breakdown after a heat soak event. Sat stationary in traffic, and then nailing it is well proven to create the correct environment for a bore score. Whether you’re using expensive 99ron fuel, or cheap supermarket 95, will make no difference in this instance.

maz8062 said: The difficulty that your friend now has is that now he knows. He knows that his car is afflicted with one of the most expensive, ruinous issues that these .1 cars have. Ignorance is bliss as the saying goes but now he can no longer feign ignorance of the car’s issues. That is why it was a mistake to be persuaded into a borescope during the spark plug change. What to do? He really only has one choice - save the pennies and get the engine rebuilt. Trying to sell the car as is will hit him in the wallet. Lying or trying to hide the issue is not what one would expect for an elderly gentleman, anyone even, so he’s stuck with it. This is what the repair industry want to happen - they want folk to borescope their cars, at PPI, service or whenever because they know that once you know you have to fix it. Good luck and try and get the work done before inflation makes it even more difficult to contemplate. It's funny you say that as he has spoken to a few specialists (although allergic to the internet he's on the phone all the time) and they all said change the oil yearly and absolutely don't rebuild it until issues start. One said he's yet to see a 3.8 not score slightly on a borescope in 5 or 6. With regard to WBAC I put the reg and mileage in and they offer peanuts. Must have researched.....

Discombobulate said: GTRene said: in the video's they speak of, watch out for to rich fuel (to much or how you say that) = wash away oil film wrong cheap fuel = not good, only 98+ best stuf use! many 'porsche' drivers seem to use the cheaper or 95+ octane or lower? or bio fuel, just stop that! lol, thats bad! and you are fooling yourself, cheap = using more fuel and more damage to your engine = way more expensive then you think you can save. and use good engine oil, so you can use a second hand Porsche from say 4 other owners each choosing their own fuel, maybe the first one asked the dealer, or looked in the book, yes you can use bio added fuel... or Ron92/95? or with 10% bio? and used that for years, by the time another Porsche lover buys such Porsche it can already have the first signs, or just not... so best to use proper fuel, only the best and make sure the engine is properly adjusted, not running too rich, to avoid bore wash. so you can postpone the major damage, some can drive many more miles with the right treatment I guess. Both may help. But it's a design / manufacturing flaw. Our first 997 was still on its factory oil, was only filled up with good fuel and run in and driven carefully and it needed a new engine at 7,500 miles. ow, wow that is indeed not normal, that would scare me, normally Porsche engines can be pretty good and strong, of course some type engines better then others. btw, How are those late Porsche 993 engines with their 3.6 air-cooled engines doing in this scary bore score stories? (asking for a friend lol) I ask since I have a eye on a nice lightweight restomod with such engine in it and more then 320hp (normally they have 285 or so.) I can't remember if those engines are fragile, maybe on other points as every type engine have something, one simple other sorts with scary bills.

Slippydiff said: GTRene said: Discombobulate said: GTRene said: in the video's they speak of, watch out for to rich fuel (to much or how you say that) = wash away oil film wrong cheap fuel = not good, only 98+ best stuf use! many 'porsche' drivers seem to use the cheaper or 95+ octane or lower? or bio fuel, just stop that! lol, thats bad! and you are fooling yourself, cheap = using more fuel and more damage to your engine = way more expensive then you think you can save. and use good engine oil, so you can use a second hand Porsche from say 4 other owners each choosing their own fuel, maybe the first one asked the dealer, or looked in the book, yes you can use bio added fuel... or Ron92/95? or with 10% bio? and used that for years, by the time another Porsche lover buys such Porsche it can already have the first signs, or just not... so best to use proper fuel, only the best and make sure the engine is properly adjusted, not running too rich, to avoid bore wash. so you can postpone the major damage, some can drive many more miles with the right treatment I guess. Both may help. But it's a design / manufacturing flaw. Our first 997 was still on its factory oil, was only filled up with good fuel and run in and driven carefully and it needed a new engine at 7,500 miles. ow, wow that is indeed not normal, that would scare me, normally Porsche engines can be pretty good and strong, of course some type engines better then others. btw, How are those late Porsche 993 engines with their 3.6 air-cooled engines doing in this scary bore score stories? (asking for a friend lol) I ask since I have a eye on a nice lightweight restomod with such engine in it and more then 320hp (normally they have 285 or so.) I can't remember if those engines are fragile, maybe on other points as every type engine have something, one simple other sorts with scary bills. Oil leaks from cylinder base gaskets, crankcase through bolts/seals, head gaskets/seals, plastic rocker covers, sticky/failed hydraulic tappets, worn valve guides. Apart from that, they’re bulletproof ... I guess (hope) that sounds a bit better then bore scoring

anonymous said: [redacted] I could live with some of those problems, a bit leaking/sweating, ok, worn items in the engine does not sound good/fine, although if its in the heads, maybe its? no engine out? or does such mean like the tappets, also engine out? also, worn tappets I guess you can hear it, but then again, bore scoring going on for a while you can hear that as well for people who know how such sounds. would not be so nice if you buy a great porsche still sounding good so far you know, goes bad in say 4-5k miles... then it gets expensive pretty fast without warranty.

GTRene said: I could live with some of those problems, a bit leaking/sweating, ok, worn items in the engine does not sound good/fine, although if its in the heads, maybe its? no engine out? or does such mean like the tappets, also engine out? also, worn tappets I guess you can hear it, but then again, bore scoring going on for a while you can hear that as well for people who know how such sounds. would not be so nice if you buy a great porsche still sounding good so far you know, goes bad in say 4-5k miles... then it gets expensive pretty fast without warranty. I'm no air cooled nerd but I believe these have separate barrels or parts per cylinder. So effectively 6 blocks bolted together. Porsche simplified their engines when they went water cooked which have 2 blocks, I think identical, so one per side with 3 pots each. The air cooled boys did indeed used to talk about top end rebuilds. So you could do the top [or far sides] of the engine and leave the rest as is. Nowadays the game has changed and the price of these cars has escalated so I'm not sure if this is still a thing. It's not just the owners cashing in. The ecosystem of specialists willing to tackle these jobs will be trying to cash in as well.

“Water cooked”

My old 987.1 Cayman S had light scuffing/scoring when I bought it 11 years ago. It's now owned by a friend and has about 50k more miles but still uses minimal oil, around 10K miles per litre and consumption has not measurably changed in that time. Thoroughly warmed up every journey and never laboured. So no, it does not always get worse.

bluetigerandy said: On a borescope my friend's car (he is in his early 70s and not really an internet user) has signs of early scoring in cylinder 6. Its a 997.1 C2S. He had asked for it to be checked during a plug change. Running well, needing no oil top ups between changes (approx 3000 miles). No external signs etc. Has anyone had a car like this that has run well long term and not had things progress? Or when scoring starts is progression a certainty? Thanks In the absence of other corroborating evidence, unless someone like Hartech told me it was scored, I would take any 3rd party analysis with a pinch of salt. Interpreting what is and isn’t normal in relation to scoring can be quite an art as far as I’ve been told.

NRG1976 said: In the absence of other corroborating evidence, unless someone like Hartech told me it was scored, I would take any 3rd party analysis with a pinch of salt. Interpreting what is and isn’t normal in relation to scoring can be quite an art as far as I’ve been told. It’s not really an art, a scored cylinder bore is quite obvious to see with a simple camera inserted through the spark plug socket. Cylinders 5&6 are the first to inspect, you may need to rotate the engine 1/2 a turn to get the pistons at the bottom of the stroke, but even though the scoring begins at the bottom of the stroke, once it’s begun, it soon spreads to the upper part of the cylinder making it visible wherever the piston happens to be when you inspect. FYI, here’s 2 images of cylinder bores from different 987 Cayman S. the first image is a 987 s with 156k miles, no rebuild. Bores are as clean as can be. Second image is a 987 S with 89k miles, I didn’t really need to do a bore scope inspection as the piston slap noise at idle was audible from 50m away…!

2nd image - 89k mile 987S

3rd image - this is a 987 S tip, 75k miles. Correct service history. Very early signs of scoring in cylinder 6. Engine is silent at hot idle. Doesn’t burn oil. Will inspect again in a year.

anonymous said: [redacted] With any engine related work on an air cooled car it's a case of take the equivalent price on a water cooled car and triple it.

flat6crocer said: 9A1 failure rate is a tiny fraction of M97 failure rate. Not remotely comparable. People forget that the early 9x7.2 cars are now nearly 15 years old (first 997.2 were late 2008). With 9x7.1 cars, they were chucking in new engines at scale under warranty from the get go. When you have Hartech having to post online repeatedly because they can't find a borked one to do their development work, you know they aren't going pop with much frequency: http://www.911uk.com/viewtopic.php?p=1644727 For the OP, think it's fair to say scoring can progress at different rates. Some can go 10s of thousands of miles slow getting worse, others can go from first signs of increasing oil consumption to knacker in well under 10k miles. I think anecdotally it seems like the ones that fail at lower miles are the ones that fail fast. There's a Youtube channel (man in a tiny garage - or something like that) of a British guy in the US that picked up a borked 991 at only 30k miles. He takes the engine apart and I'm sure it's borescoring that killed that. Also been a few on Rennlist. They do seem to be few and far between though and I guess could be a bad batch of cylinders or something rather than the ticking time bomb affecting nearly all 997.1

IREvans said: 2nd image - 89k mile 987S ooh, that does indeed not look good and must have made some noises, different then tapping 'valve's ' good it be the same-ish sounds as piston slap as some older cars could make when yoy say accelerated in 4th or so from low rpm and then could cause in some cases piston slap? noises?

nunpuncher said: flat6crocer said: 9A1 failure rate is a tiny fraction of M97 failure rate. Not remotely comparable. People forget that the early 9x7.2 cars are now nearly 15 years old (first 997.2 were late 2008). With 9x7.1 cars, they were chucking in new engines at scale under warranty from the get go. When you have Hartech having to post online repeatedly because they can't find a borked one to do their development work, you know they aren't going pop with much frequency: http://www.911uk.com/viewtopic.php?p=1644727 For the OP, think it's fair to say scoring can progress at different rates. Some can go 10s of thousands of miles slow getting worse, others can go from first signs of increasing oil consumption to knacker in well under 10k miles. I think anecdotally it seems like the ones that fail at lower miles are the ones that fail fast. There's a Youtube channel (man in a tiny garage - or something like that) of a British guy in the US that picked up a borked 991 at only 30k miles. He takes the engine apart and I'm sure it's borescoring that killed that. Also been a few on Rennlist. They do seem to be few and far between though and I guess could be a bad batch of cylinders or something rather than the ticking time bomb affecting nearly all 997.1 I've heard of several injector issues on 991.1s causing scoring. In the USA this would be more likely as their fuel is naff. The theory is the fuel isn't atomising properly and breaking down the oil film, rather than cylinder distortion and other mechanisms believed to affect the M97.

NRG1976 said: bluetigerandy said: On a borescope my friend's car (he is in his early 70s and not really an internet user) has signs of early scoring in cylinder 6. Its a 997.1 C2S. He had asked for it to be checked during a plug change. Running well, needing no oil top ups between changes (approx 3000 miles). No external signs etc. Has anyone had a car like this that has run well long term and not had things progress? Or when scoring starts is progression a certainty? Thanks In the absence of other corroborating evidence, unless someone like Hartech told me it was scored, I would take any 3rd party analysis with a pinch of salt. Interpreting what is and isn’t normal in relation to scoring can be quite an art as far as I’ve been told. Thanks- Hartech were not overly concerned. Advised to enjoy the car and not worry.