4.7 engine failures
Discussion
Hi all
I looking at returning to the Aston fold. I previously had a 2007 4.3 Vantage. The car was great and at the time there wasn't any scare stories as far as I remember with either sub frames and engine failures. I've been watching a few videos from Bamford and Rose on the subject of both and didn't realise that catastrophic engine failures were becoming more common, particularly on the 4.7 on the V8's.
https://www.youtube.com/watch?v=jcNrjCzn5Sk
I'd be interested to know how serious the issue is. Are engine failures few and far between or are they becoming quite common and more of when not if issue, a bit like with 997.1 Porsche 911's? I'm currently looking at a 4.7 S and some of the numbers quoted here for engine rebuild costs are pretty eye watering.
Thanks
Trev
I looking at returning to the Aston fold. I previously had a 2007 4.3 Vantage. The car was great and at the time there wasn't any scare stories as far as I remember with either sub frames and engine failures. I've been watching a few videos from Bamford and Rose on the subject of both and didn't realise that catastrophic engine failures were becoming more common, particularly on the 4.7 on the V8's.
https://www.youtube.com/watch?v=jcNrjCzn5Sk
I'd be interested to know how serious the issue is. Are engine failures few and far between or are they becoming quite common and more of when not if issue, a bit like with 997.1 Porsche 911's? I'm currently looking at a 4.7 S and some of the numbers quoted here for engine rebuild costs are pretty eye watering.
Thanks
Trev
There is a thread on this
I can't seem to link it but search Aston engine failure and it will be there 6 pages of discussion from 2022
I have had mine only 14 months, but I intend to keep the Timeless Warranty for as long as possible, in hope that it helps out of the worst happens, but as someone once said, it is better to have loved and lost, than never loved at all, and I think Aston ownership is a bit like that, if mine goes pop then so be it, the journey would still have been worth it
Kev
I can't seem to link it but search Aston engine failure and it will be there 6 pages of discussion from 2022
I have had mine only 14 months, but I intend to keep the Timeless Warranty for as long as possible, in hope that it helps out of the worst happens, but as someone once said, it is better to have loved and lost, than never loved at all, and I think Aston ownership is a bit like that, if mine goes pop then so be it, the journey would still have been worth it
Kev
Edited by kevin_cambs_uk on Saturday 15th July 12:25
Edited by kevin_cambs_uk on Saturday 15th July 12:26
I think I found the thread you were referring to. It doesn’t seem to give any idea of how susceptible the v8’s are to engine failures but covers some of the most probable causes for them.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
It’s a tricky one as I’d definitely consider a timeless warranty for peace of mind but the car is a 2012 and therefore outside the timeless coverage of up to 10 years.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
It’s a tricky one as I’d definitely consider a timeless warranty for peace of mind but the car is a 2012 and therefore outside the timeless coverage of up to 10 years.
Interesting
I just renewed my warranty. The car was registered may 2013 and I bought it last year in may so turned 10 this may but they took the warranty money for its 11th year like a shot!!!
There will be some people along who know a hell of a lot more than me who can post their wisdom but I suspect t they are out with their cars as I write!
Kev
I just renewed my warranty. The car was registered may 2013 and I bought it last year in may so turned 10 this may but they took the warranty money for its 11th year like a shot!!!
There will be some people along who know a hell of a lot more than me who can post their wisdom but I suspect t they are out with their cars as I write!
Kev
Edited by kevin_cambs_uk on Saturday 15th July 15:48
There is another aspect involved.
Having a warranty may not help, because we have been told on here, that Aston Martin are no longer supplying replacement V8 engines.
Bamford Martin are rebuilding some, but I suppose they might be very limited, because presumably there are not many blocks or heads available.
If we think about Works and still being able to build 1960s six cylinder engines, they must somehow have made arrangements for blocks and heads to be produced. Hopefully a similar arrangement will happen for the VH V8.
The last V8 I think was a Vantage sold in 2019. Think manufacturers are supposed to adhere to some sort of obligation, to supply spares for quite a few years, not cease after just 4 years.
What we don't seem to know, is whether there is pattern to failures, or whether these are just isolated breakages.
Go on any single make car forum and no doubt you will failures, even Toyota.
I dont see Aston Martin on this list, so the failures must be statistically insignificant perhaps ?
https://www.thecarexpert.co.uk/most-reliable-engin...
Aftermarket warranty companies must have a fair idea, at least enough to ensure they make money rather than lose money on a particular model. The cost and ease of buying such a warranty may give some indication. Just buy a warranty if you want that piece of mind and get on with enjoying the car.
I dont see Aston Martin on this list, so the failures must be statistically insignificant perhaps ?
https://www.thecarexpert.co.uk/most-reliable-engin...
Aftermarket warranty companies must have a fair idea, at least enough to ensure they make money rather than lose money on a particular model. The cost and ease of buying such a warranty may give some indication. Just buy a warranty if you want that piece of mind and get on with enjoying the car.
I had an 07 vantage before with an aftermarket warranty so I’m totally aware that I might be able to get one for additional peace of mind but like I said I stumbled across the bamford rose video and it set off alarm bells thinking that engine failures had become a new issue that was starting to become more common with potentially a £20k rebuild cost.
It sounds like this isn’t a widespread issue though from responses on here and not something you aware of like the dreaded ims and borescoring issues of 996/997.1 Porsches for example. I just want to go into Aston ownership with my eyes open to any potential issues so I can enjoy the car and not be constantly worrying.
It sounds like this isn’t a widespread issue though from responses on here and not something you aware of like the dreaded ims and borescoring issues of 996/997.1 Porsches for example. I just want to go into Aston ownership with my eyes open to any potential issues so I can enjoy the car and not be constantly worrying.
I spent a couple of years on this forum before buying a 4.7 , and never heard of any v8 engine issues in that time. I was pretty comfortable getting one from a reliability perspective. I think one story emerged not so long ago but that’s all I remember. Of course that’s not scientific , but in comparison there was much more talk of engine issues on the Porsche sites when I was looking at 996/997 a few years before that ( hence scratching that itch with a much safer bet for the money at the time 996 metzger engined turbo)
codieskid said:
Hi all
............I'm currently looking at a 4.7 S and some of the numbers quoted here for engine rebuild costs are pretty eye watering.
Thanks
Trev
Get the AMG engined vantage and you'll have no worries. Now excuse me as I make my way down the alley to line up for the firing-squad I deserve for this comment............I'm currently looking at a 4.7 S and some of the numbers quoted here for engine rebuild costs are pretty eye watering.
Thanks
Trev
Edited by PinkHouse on Tuesday 18th July 09:29
Until fairly recently V8 engine failure was almost unheard of, however in the last couple of years there have been two or three discussed on this forum.
As ‘engine failure’ can mean anything, it’s useful in any discussion to focus on facts and evidence gained post failed engine strip where primary failure mode can be established. instrumentation data & metallurgical analysis would confirm root cause, though such forensic investigation would typically only happen during the manufacturers engine development phase. Post production sign off, engine data and metallurgical analysis might be undertaken in event of suspected serial defect (quality issue) or in case of disputed/rejected major warranty claim.
In absense of such detailed analysis, then the most likely root cause of any engine failure can often be reasonably hypothesised using a mixture of the evidence from the post failure strip down and experience.
V8 engine failure hard evidence is fairly scant, all I have seen so far on the V8 failures is evidence of a valve drop and big end (rod) bearing failure. I’ve seen a video of a car still running with what is clearly rod bearing failure.
On the valve drop, there are really only two probable causes, a quality issue with the valve itself, or operating out of design envelope (engine overspeed). Some would also highlight overheating (eg head gasket), though this would be a different root cause, not directly related to an issue with component quality or operation. In that case, valve failure would be considered a secondary failure. The likelihood of valve drop through overspeed is higher with manual gearbox, as the ASM system makes accidental selection of wrong gear impossible. Cars that are ‘tuned’ where the rev limiter is lifted a few hundred rpm, and/or that are regularly tracked and spend higher proportions of the operational lives pushing the limits of the design operational envelope are also naturally going to present higher risk of failure. It is a risk that anyone who tracks their car will generally understand and be ready to accept.
Big end bearing failure is perhaps the more common failure mode. Much has been made of the design and metallurgy of the rod bearing shells in the Aston V8, they are not particularly exotic. However, they were designed, developed and validated by the factory under Ford ownership and using Ford processes, even the 4.7 where validation of the increased capacity engine continued in the AMEP post AML disposal.
The AML cross plane V8 is designed with very tight bearing clearances to run on a fairly viscous (when cold) synthetic oil, and can operate at high speed, similar to the contemporary, even higher speed flat plane BMW V8 (as fitted to the E90/92 M3). That engine, made in far greater numbers is known for rod bearing failure. Interestingly, it is designed to run on the same grade of oil as the AML V8.
These types of engine design are vulnerable when operated at high speed and load from cold, where components have not fully thermally expanded into their working ‘hot’ form, clearances are minimal and oil is cold. Contact, pick-up and galling ultimately leading to premature bearing failure is by by far most likely where the engine is taken to high load or speed from cold. The risks increase as the engines oil ages and products of combustion degrade the oil and increase cold viscosity.
Thus, to minimise the chance of premature engine failure, the advice would remain the same as it has always been. Use high quality oil, change it frequently, keep it topped up, and thoroughly warm up the engine before using it hard.
Though this advice will seem obvious to all reading this, there is an increasingly large cohort of younger drivers, who are growing up with modern vehicles with cold limiters and all manner of nanny systems to prevent engine damage when cold, and as a direct consequence, they are slowly becoming increasingly less likely fully grasp just how important it is to warm an engine before subjecting it to high load or speed. Evidence any number of the you tube ‘influencer’ videos where they jump in an apparently cold car (I appreciate it often won’t be) and rev the engine to the limiter. As more older cars find their way into the hands of those who perhaps do not fully appreciate just how critical it is to let these highly tuned close tolerance aluminium engines achieve full operating temperature, or even how important checking and changing the oil is, we can perhaps expect to hear of more failures.
Finally, even with a sample size as (relatively) small as the AML V8 4.3 and 4.7 n/a production run, statistically, there will be the odd ‘outlier’, where no matter how much love and care and attention is lavished on the car, the engine will inexplicably fail due to a random quality defect. All we can do is trust to luck that it won’t happen to us, or buy an aftermarket warranty.
As ‘engine failure’ can mean anything, it’s useful in any discussion to focus on facts and evidence gained post failed engine strip where primary failure mode can be established. instrumentation data & metallurgical analysis would confirm root cause, though such forensic investigation would typically only happen during the manufacturers engine development phase. Post production sign off, engine data and metallurgical analysis might be undertaken in event of suspected serial defect (quality issue) or in case of disputed/rejected major warranty claim.
In absense of such detailed analysis, then the most likely root cause of any engine failure can often be reasonably hypothesised using a mixture of the evidence from the post failure strip down and experience.
V8 engine failure hard evidence is fairly scant, all I have seen so far on the V8 failures is evidence of a valve drop and big end (rod) bearing failure. I’ve seen a video of a car still running with what is clearly rod bearing failure.
On the valve drop, there are really only two probable causes, a quality issue with the valve itself, or operating out of design envelope (engine overspeed). Some would also highlight overheating (eg head gasket), though this would be a different root cause, not directly related to an issue with component quality or operation. In that case, valve failure would be considered a secondary failure. The likelihood of valve drop through overspeed is higher with manual gearbox, as the ASM system makes accidental selection of wrong gear impossible. Cars that are ‘tuned’ where the rev limiter is lifted a few hundred rpm, and/or that are regularly tracked and spend higher proportions of the operational lives pushing the limits of the design operational envelope are also naturally going to present higher risk of failure. It is a risk that anyone who tracks their car will generally understand and be ready to accept.
Big end bearing failure is perhaps the more common failure mode. Much has been made of the design and metallurgy of the rod bearing shells in the Aston V8, they are not particularly exotic. However, they were designed, developed and validated by the factory under Ford ownership and using Ford processes, even the 4.7 where validation of the increased capacity engine continued in the AMEP post AML disposal.
The AML cross plane V8 is designed with very tight bearing clearances to run on a fairly viscous (when cold) synthetic oil, and can operate at high speed, similar to the contemporary, even higher speed flat plane BMW V8 (as fitted to the E90/92 M3). That engine, made in far greater numbers is known for rod bearing failure. Interestingly, it is designed to run on the same grade of oil as the AML V8.
These types of engine design are vulnerable when operated at high speed and load from cold, where components have not fully thermally expanded into their working ‘hot’ form, clearances are minimal and oil is cold. Contact, pick-up and galling ultimately leading to premature bearing failure is by by far most likely where the engine is taken to high load or speed from cold. The risks increase as the engines oil ages and products of combustion degrade the oil and increase cold viscosity.
Thus, to minimise the chance of premature engine failure, the advice would remain the same as it has always been. Use high quality oil, change it frequently, keep it topped up, and thoroughly warm up the engine before using it hard.
Though this advice will seem obvious to all reading this, there is an increasingly large cohort of younger drivers, who are growing up with modern vehicles with cold limiters and all manner of nanny systems to prevent engine damage when cold, and as a direct consequence, they are slowly becoming increasingly less likely fully grasp just how important it is to warm an engine before subjecting it to high load or speed. Evidence any number of the you tube ‘influencer’ videos where they jump in an apparently cold car (I appreciate it often won’t be) and rev the engine to the limiter. As more older cars find their way into the hands of those who perhaps do not fully appreciate just how critical it is to let these highly tuned close tolerance aluminium engines achieve full operating temperature, or even how important checking and changing the oil is, we can perhaps expect to hear of more failures.
Finally, even with a sample size as (relatively) small as the AML V8 4.3 and 4.7 n/a production run, statistically, there will be the odd ‘outlier’, where no matter how much love and care and attention is lavished on the car, the engine will inexplicably fail due to a random quality defect. All we can do is trust to luck that it won’t happen to us, or buy an aftermarket warranty.
Edited by Calinours on Tuesday 18th July 09:49
Calinours said:
All we can do is trust to luck that it won’t happen to us, or buy an aftermarket warranty.
No one has yet answered my earlier query about this point.
Someone mentioned a conversation with a main dealer. "We have two cars here with broken engines".
Therefore an engine breaks, warranty agree to pay for replacement engine, Aston Martin are not supplying replacement engines.
What happens next ?
Does the car just remain unusable at the dealer indefinitely ?
Having a warranty would not appear to help.
The answer is that their engines will have to be rebuilt.
How do we all imagine all those 40, 50, 60yr old and beyond vehicles are kept running when all of their ‘engines’ have been out of production for decades?
It’s down to the fact that an ‘engine’ is not a single contiguous component, it’s a collection of components, any one of which can result in ‘engine failure’. Thus, as long as some alternative component remains available, and it generally does, then the engine can be rebuilt. There remain lots of specialist companies making pistons, rings, rods, cranks, cams, liners, bearings, seals, valves etc. Thus, assuming residual values justify the ever increasing specialist labour costs, practically any engine can be maintained indefinitely, almost regardless of the number of failures.
The only types of failure that become problematic are where one of the blocks is totalled, eg a rod through the side. Even then, many may be surprised what can be done with aluminium welding. It was and remains common practise with 50s and 60s AM in-line six failed blocks to be built up with weld, re machined and put back into service, though such repair options are more limited given the complexity, reduced mass and lower peak stress limits of more modern cast aluminium blocks. There’s less headroom in modern designs, however, solutions for all but the most catastrophic destruction will be developed.
As ever, necessity is the mother of invention. If second hand good condition blocks become scarce and cost-prohibitive, then, where the market demands, specialists will develop solutions for even the trickiest of problems, for example the current challenge of removing cast-in liners.
In conclusion, it will always be possible to repair and rebuild these engines, as it is with practically every other engine ever made. It will just be a matter of cost, and if costs rise too much, competition will, to a significant degree, ensure costs are kept reasonable, as it does for the rebuild costs of the old AM straight sixes and V8’s, which have been out of production for decades.
How do we all imagine all those 40, 50, 60yr old and beyond vehicles are kept running when all of their ‘engines’ have been out of production for decades?
It’s down to the fact that an ‘engine’ is not a single contiguous component, it’s a collection of components, any one of which can result in ‘engine failure’. Thus, as long as some alternative component remains available, and it generally does, then the engine can be rebuilt. There remain lots of specialist companies making pistons, rings, rods, cranks, cams, liners, bearings, seals, valves etc. Thus, assuming residual values justify the ever increasing specialist labour costs, practically any engine can be maintained indefinitely, almost regardless of the number of failures.
The only types of failure that become problematic are where one of the blocks is totalled, eg a rod through the side. Even then, many may be surprised what can be done with aluminium welding. It was and remains common practise with 50s and 60s AM in-line six failed blocks to be built up with weld, re machined and put back into service, though such repair options are more limited given the complexity, reduced mass and lower peak stress limits of more modern cast aluminium blocks. There’s less headroom in modern designs, however, solutions for all but the most catastrophic destruction will be developed.
As ever, necessity is the mother of invention. If second hand good condition blocks become scarce and cost-prohibitive, then, where the market demands, specialists will develop solutions for even the trickiest of problems, for example the current challenge of removing cast-in liners.
In conclusion, it will always be possible to repair and rebuild these engines, as it is with practically every other engine ever made. It will just be a matter of cost, and if costs rise too much, competition will, to a significant degree, ensure costs are kept reasonable, as it does for the rebuild costs of the old AM straight sixes and V8’s, which have been out of production for decades.
Edited by Calinours on Tuesday 18th July 11:36
Thanks everyone for the comments so far on the subject and Calinours for your in depth response, it was really helpful and helped highlight the importance of warming up the cars and maintaining the engine the right way.
I was genuinely starting to worry that this might be another Porsche 997.1 scenario where there are many cars suffering the same fate but it appears there are a few cars out there but this isn't a pandemic of engine failures. I feel a bit more confident it dipping my toe back into Aston ownership again but will try and see what after market warranties are available for a bit of additional peace of mind.
Trev
I was genuinely starting to worry that this might be another Porsche 997.1 scenario where there are many cars suffering the same fate but it appears there are a few cars out there but this isn't a pandemic of engine failures. I feel a bit more confident it dipping my toe back into Aston ownership again but will try and see what after market warranties are available for a bit of additional peace of mind.
Trev
Jon39 said:
Calinours said:
All we can do is trust to luck that it won’t happen to us, or buy an aftermarket warranty.
No one has yet answered my earlier query about this point.
Someone mentioned a conversation with a main dealer. "We have two cars here with broken engines".
Therefore an engine breaks, warranty agree to pay for replacement engine, Aston Martin are not supplying replacement engines.
What happens next ?
Does the car just remain unusable at the dealer indefinitely ?
Having a warranty would not appear to help.
Mike at BR said previously he reckons nearly all 4.7s will need a rebuild or serious attention after approx 70-80k due to poor manufacturing techniques of the bearings. Some were not sprayed with the final coating correctly in manufacture due to the way they were positioned for spraying - all bearings went into stock randomly together so some engines may be full of poor bearings, some only 1 or 2, and if you're lucky, none.
I don't have a 4.7 so nothing to gain with me for saying that!
I don't have a 4.7 so nothing to gain with me for saying that!
I don`t hear/read about 4.3 engines needing rebuilds, but it has popped up a few times with the 4.7, and I for sure know of two, one of which I was present for when it blew it`s bottom end out. I believe for the most part they are a solid and reliable motor, but seems if it is in that small percentage that has a major issue, it is more likely to be a 4.7.
Just an observation, I`m no expert.
Just an observation, I`m no expert.
Krhuangbin said:
Mike at BR said previously he reckons nearly all 4.7s will need a rebuild or serious attention after approx 70-80k due to poor manufacturing techniques of the bearings. Some were not sprayed with the final coating correctly in manufacture due to the way they were positioned for spraying - all bearings went into stock randomly together so some engines may be full of poor bearings, some only 1 or 2, and if you're lucky, none.
I don't have a 4.7 so nothing to gain with me for saying that!
Ok so all 4.7s have this big bill waiting for them ..supposed Id better get my car down to the dealer for an upgrade then I don't have a 4.7 so nothing to gain with me for saying that!
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