Who has worn out their XK8 / XKR engine ??
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Who has worn out their XK8 / XKR engine, or knows of someone who has worn one out, i.e. needed to have the crankshaft replaced or re-ground. Or even just needed oversize pistons due to wear.
Hearsay evidence accepted.
I'm asking because I've been reading on the forum statements by knowledgable members (and moderators) that one can expect to get 250,000 miles of engine life.
Coming from a classic car restoration background, that number seems awfully low to me. For example, Fords classic 289 cubic inch engine is good for 250,000 to 300,000 miles after a routine machine shop rebuilding before needing new engine internals. That's without the benefit an engine-life extending features like fuel injection, electronic ignition, an d advanced metallurgy. And machine shops don't generally have the same state-of-the-art engine building equipment that automobile manufacturers use. During a recent discussion with an engineer from Blackstone Labs (oil testing), I was told that from their observations, the 4.0 liter XK8 / XKR engines should be good for 400,000 miles before needing overhauling or replacement. Which is more in line with my guess-estimates on the subjects.
Real life stories, and all opinions are sought, so what say ye ?
Z
I'm often guilty of not seeing the forrest for the trees, so is there something obvious I'm missing here ?
Hearsay evidence accepted.
I'm asking because I've been reading on the forum statements by knowledgable members (and moderators) that one can expect to get 250,000 miles of engine life.
Coming from a classic car restoration background, that number seems awfully low to me. For example, Fords classic 289 cubic inch engine is good for 250,000 to 300,000 miles after a routine machine shop rebuilding before needing new engine internals. That's without the benefit an engine-life extending features like fuel injection, electronic ignition, an d advanced metallurgy. And machine shops don't generally have the same state-of-the-art engine building equipment that automobile manufacturers use. During a recent discussion with an engineer from Blackstone Labs (oil testing), I was told that from their observations, the 4.0 liter XK8 / XKR engines should be good for 400,000 miles before needing overhauling or replacement. Which is more in line with my guess-estimates on the subjects.
Real life stories, and all opinions are sought, so what say ye ?
Z
I'm often guilty of not seeing the forrest for the trees, so is there something obvious I'm missing here ?
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GGG (02-12-2019)
#3
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the reason for the 250K cap might be that these engines "expire" when some major part breaks as opposed to simply wearing out where bearings are shot to the point of lower oil pressure and cylinder compression is too low. the older engines mentioned were less complex and one does not have a cooling system that needs to be re plumbed every ten or so years. one good over heat and here comes a dropped valve seat. in other cases some "small" malfunction, perhaps unanticipated, mechanically destroys a major part of the engine. the engine is now considered done and probably the car. many engines that are not worn beyond fixing are probably written off as the cost of repair is considered not worth it given the current collectible value of an equally aged car with its own items wearing and failing.
a collectible Mustang with its original engine is a recognized classic, so an owner will keep up with repairs over the expecting wear life of the engine and these "little" repairs are easier to identify before disaster and less expensive to address over the engine's wear lifetime. those of us who like our particular cars will watch things and make repairs to keep the problem from mushrooming into total failure. however, the reality might be that we do not have time or opportunity to put on much mileage, so it is hard to test the theory. case in point, a mechanic that i know specializing in another brand has cautioned that upgrading the tensioners or having the good ones from the start might not be a set-it-and-forget-it action. timing chains have expected lifetimes, and many are not for the lifetime of the engine. Some fine older Mercedes Benz cars are an example. how will we find out other than bang at some mileage. since you are racking up miles, it is obvious that your driving areas and trips are conducive to this. these type of highway and long distance runs are easier on the engine, thus you might be able to achieve very high mileage as opposed to a lower usage car where things rot and heat-sink to oblivion.
a collectible Mustang with its original engine is a recognized classic, so an owner will keep up with repairs over the expecting wear life of the engine and these "little" repairs are easier to identify before disaster and less expensive to address over the engine's wear lifetime. those of us who like our particular cars will watch things and make repairs to keep the problem from mushrooming into total failure. however, the reality might be that we do not have time or opportunity to put on much mileage, so it is hard to test the theory. case in point, a mechanic that i know specializing in another brand has cautioned that upgrading the tensioners or having the good ones from the start might not be a set-it-and-forget-it action. timing chains have expected lifetimes, and many are not for the lifetime of the engine. Some fine older Mercedes Benz cars are an example. how will we find out other than bang at some mileage. since you are racking up miles, it is obvious that your driving areas and trips are conducive to this. these type of highway and long distance runs are easier on the engine, thus you might be able to achieve very high mileage as opposed to a lower usage car where things rot and heat-sink to oblivion.
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zray (02-11-2019)
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yes, the Fords are an easy classic to keep on the road.
But regardless of the current values of the first generation of XK8 / XKR's, I hope against hope that some percentage of owners grow fond enough of the cars so hat they see a benefit, however irrational at this time, in keeping the cars maintained and driven. The car's complexities make that difficult of course. But not much more difficult than keeping in other low volume cars of the same era alive and kicking.
Z.
But regardless of the current values of the first generation of XK8 / XKR's, I hope against hope that some percentage of owners grow fond enough of the cars so hat they see a benefit, however irrational at this time, in keeping the cars maintained and driven. The car's complexities make that difficult of course. But not much more difficult than keeping in other low volume cars of the same era alive and kicking.
Z.
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Right my car has a bit of a dark history, which I have absolutely no documented evidence of. As a 1999 XK8, I suspect the AJ26 engine was swapped out at some point to my current AJ27 which now has 78,600 km on the clock. I took the car on, after it being stored for approx. 3 years.
As the main Jaguar dealer in Bahrain, has no evidence of the car being sold in Bahrain, I assume this car is a Dubai import, which isn't unusual here. So here goes for my consideration of engine mileage.
Car spent approx. 10 years in Dubai. When I was there I would average approx. 42,000km per annum so 10 x 42k = 420,000 km = approx. 260,000 miles. So this seems to marry up with your estimate of a 250,000mile engine lifespan. Quality of engine maintenance here is pretty poor, so someone swapped out the engine at this point.
Then car was in Bahrain, a small island, where you only do approx. 12,000km per year. Therefore the AJ27 engine has done 7 years @ 12,000km/year = 84k km which marries up with approx. what I see now on the clock.
As the main Jaguar dealer in Bahrain, has no evidence of the car being sold in Bahrain, I assume this car is a Dubai import, which isn't unusual here. So here goes for my consideration of engine mileage.
Car spent approx. 10 years in Dubai. When I was there I would average approx. 42,000km per annum so 10 x 42k = 420,000 km = approx. 260,000 miles. So this seems to marry up with your estimate of a 250,000mile engine lifespan. Quality of engine maintenance here is pretty poor, so someone swapped out the engine at this point.
Then car was in Bahrain, a small island, where you only do approx. 12,000km per year. Therefore the AJ27 engine has done 7 years @ 12,000km/year = 84k km which marries up with approx. what I see now on the clock.
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There are several reports on the forums of Jaguar V8's reaching and exceeding 250K miles. I suspect it is more because the XK8/XKR is not normally the daily driver of choice for most that greater mileages are not yet accumulated or reported rather than any inherent weakness in the engine. I agree with your gut feeling for 400K before overhaul is required should prove to be near the mark.
Given the initial Nikasil debacle and the on-going sensitivity to overheating if the cooling system is not maintained, engine failures are not appearing high in post topics. Where they do, it is the cylinder heads (warped with overheat or bent valves from timing chain tensioner failure); I can't recall more than a couple of reported issues with main or big end bearings and, if my memory is correct, they have been due to oil pump failures.
My feeling is the risk to XK8/XKR as the years roll by will be the electronics and not the powertrain. Transmissions are a known weakness but not too costly to overhaul. An engine rebuild will not make economic sense unless vehicle values rise. The good news there is that they are probably at the bottom now and can only go one way! However, unless an aftermarket develops to support the complex electronics, otherwise mechanically and bodily good XK8/XKR's will not have a bright future.
Graham
Given the initial Nikasil debacle and the on-going sensitivity to overheating if the cooling system is not maintained, engine failures are not appearing high in post topics. Where they do, it is the cylinder heads (warped with overheat or bent valves from timing chain tensioner failure); I can't recall more than a couple of reported issues with main or big end bearings and, if my memory is correct, they have been due to oil pump failures.
My feeling is the risk to XK8/XKR as the years roll by will be the electronics and not the powertrain. Transmissions are a known weakness but not too costly to overhaul. An engine rebuild will not make economic sense unless vehicle values rise. The good news there is that they are probably at the bottom now and can only go one way! However, unless an aftermarket develops to support the complex electronics, otherwise mechanically and bodily good XK8/XKR's will not have a bright future.
Graham
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time to buy the parts car(s) while they are still cheap. Now to convince my significant other to give up her garage parking spot for the valuable parts car !
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Z
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John Nevets (02-13-2019)
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I dream of the day when we can download the blueprint or CAD file for any plastic part for our cars and just print a new one. ECUs and other electronic parts are the real nightmares for durability.
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John Nevets (02-13-2019)
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electronic parts are not going to be the death of any car, here's why, especially for these cars. the electronics are mainstream units and conform to industry standards. they are not some inherently wacky or poor design. even without this just said there is a rule about solid state components that if they work for x number of months, they will work for a very, very long time. someone please remind me of how that saying goes exactly. next, there are people who fix this stuff as a hobby, even i do some small work. there are hobbyists that duplicate computer sound cards from scratch and other things from schematics. my own father used to open up units similar to our ECUs and a few hours later had identified everything that needed fixing. there will always be someone who for a fee will fix any of our electronics no matter how old. next, especially for the pre-2003 cars. the ECUs are even simpler little computers and the overall car is simpler in terms of electronics. no, this does not condemn the newer car, just makes the point. the controllers on our cars are Japanese electronics from a very good time of manufacture. they are not going to fail often. same with the transmission controller. better yet, they are stacked up at salvage yards and will not be discarded. BTW: with all of the stuff we complain about breaking in these online pages, ever see a lot about the ECUs and other major controller.
now for the best part. since the functionalities of the major controllers are known, it will be possible in the future to have modified or custom ECUs or tran controllers made, modified originals or sourced from other cars with modifications. this will get really fun in emissions testing states where some allow the cars to roll off testing at twenty years. you could have the options to keep full engine diagnostics while making things better than the OEMs could do. imagine deleting the EGR circuit on an XKR while eliminating any and all limp home or check engine or open loop situations. most do not realize that the VVT on the NA engine achieves EGR functionality which is why these cars do not need the dedicated circuit. welcome to better fuel economy and power.
and let's get really crazy, perhaps someone would like to run carbs while still controlling the transmission properly. this is called bespoke programming.
electronics will not kill these car, only people too cheap and/or not motivated to find options.
enthusiasts of the 80s and 90s Japanese cars, both the originality and modifier crowd have been doing all of the above for decades. these guys could work on our computers in a minute. i know, have asked a few about it. my idea is to have a custom ECU/trans controller as a plug and play switch whenever i desire. my car plan is to stay as a stock survivor switching little things for fun once in a while.
there are also companies that can make virtually any wiring harness or plug or jack for any part of any car. we have used them for years and they just made me a complete computer harness for a Japanese ECU for a full restoration.
now for the best part. since the functionalities of the major controllers are known, it will be possible in the future to have modified or custom ECUs or tran controllers made, modified originals or sourced from other cars with modifications. this will get really fun in emissions testing states where some allow the cars to roll off testing at twenty years. you could have the options to keep full engine diagnostics while making things better than the OEMs could do. imagine deleting the EGR circuit on an XKR while eliminating any and all limp home or check engine or open loop situations. most do not realize that the VVT on the NA engine achieves EGR functionality which is why these cars do not need the dedicated circuit. welcome to better fuel economy and power.
and let's get really crazy, perhaps someone would like to run carbs while still controlling the transmission properly. this is called bespoke programming.
electronics will not kill these car, only people too cheap and/or not motivated to find options.
enthusiasts of the 80s and 90s Japanese cars, both the originality and modifier crowd have been doing all of the above for decades. these guys could work on our computers in a minute. i know, have asked a few about it. my idea is to have a custom ECU/trans controller as a plug and play switch whenever i desire. my car plan is to stay as a stock survivor switching little things for fun once in a while.
there are also companies that can make virtually any wiring harness or plug or jack for any part of any car. we have used them for years and they just made me a complete computer harness for a Japanese ECU for a full restoration.
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my particular vote for what is going to get electronically annoying in these cars over the years is not the control boxes or ECUs but rather the wiring. the insulation deteriorates and causes shorts. a DIYer can learn to make a harness easily.
BTW: using arguments presented in these pages. the Japanese cars were made in much larger numbers than ours, cost much less equivalently new, are not particularly unique, always very well made. yet, their owners spend a lot for used acquisition in many cases, lavishly restore and maintain them and invest major time and monetary resources in them vastly outpacing any future value that they might have. many of these are museum like in presentation and maintenance as well as running like they were just built only exceeded by the notable achievements with the modified specimens.
Last edited by CorStevens; 02-14-2019 at 11:30 AM. Reason: additions
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