Early XK8's and the Nikasil Engine Problem
Discussion
For a while now I've been thinking about buying an XJS, but then saw that the early XK8's are falling into my budget (£5k ish). Having looked around the internet for buying advice, one thing that has come up that worries me is the Nikasil liners on the pre 2000 models (which is what I would go for in my budget). However, I've also heard that now we have the lower sulphur petrol, this should no longer be a problem.
My question to the collective PH wisdom is, am I right to be worried about the engines on early XK8's or are all the problems a thing of the past?
I may have just been lucky but I bought a new XK8 in 1996 just after they were released. Did 80,000 miles in 18 months and only issues were
Condensation in headlamp units
Wheels [ 18"] were replaced FOC 4 times
Front nose cone was repainted twice as colour didnt exactly match.
More techie Jaguar fans will be along to refer to the Nikasil issue. I have a 98 840 now and earlier versions [ 4ltr ] suffered from the same problems.
Condensation in headlamp units
Wheels [ 18"] were replaced FOC 4 times
Front nose cone was repainted twice as colour didnt exactly match.
More techie Jaguar fans will be along to refer to the Nikasil issue. I have a 98 840 now and earlier versions [ 4ltr ] suffered from the same problems.
Generally speaking, there is no Nikasil issue. Its been a long time since the petrol was phased out year 2000 so if the car runs smooth now, you will be fine.
Also look out for the following issues....
Underneath front footwell outer corners have plates on that can rust through, look underneath & poke with a screwdriver, its a £400 welding job to remove & fix.
Engine cam chain tensioners are made of plastic and can be known to break up, thus causing chains to jump and bent valves etc. Tensioners are regularly replaced for mk3 metal ones, ask the question, budget 1000 or take the risk.
Otherwise the engines are bullet proof and good for 200k+
if you want more research, try www.xkec.co.uk
Also look out for the following issues....
Underneath front footwell outer corners have plates on that can rust through, look underneath & poke with a screwdriver, its a £400 welding job to remove & fix.
Engine cam chain tensioners are made of plastic and can be known to break up, thus causing chains to jump and bent valves etc. Tensioners are regularly replaced for mk3 metal ones, ask the question, budget 1000 or take the risk.
Otherwise the engines are bullet proof and good for 200k+
if you want more research, try www.xkec.co.uk
It's pretty unlikley Nicasil coating failure will be a problem now. Not all pre 2000 cars were affected in any case and it only occured under a particular set of circumstances involving the use of high Sulphur fuel and repeated short trips. Not all fuel available in the mid 90's had the maximum allowable 150ppm in any case. There is a reasonable arguement that a Nicasil engine in good condition is actually better than a later one with steel liners due the advantages of a Nicasil coating over steel.
Nicasil failure is indicated by a reluctance to start, lumpy idle and the presence of engine oil in the induction system - it's classic loss of compression leading to excess pressurisation of the crankcase. If you're worried you can have a blow by test done, and should see less than 25l/m on a healthy engine.
Jaguar heavily revised the V8 alongside the intorduction of steel liners and introduced a different throttle body and waterpump - both of which had caused grief on earlier cars. Throttle bodies should have been changed under recall which has only recently been withdrawn, the plastic impellors on early water pumps fell off leading to overheating and thremostats occasionally failed too. The secondary timing chain tensioners were revised with another plastic bodied design which also failed over time with the disadvntage you'd not get the early warning rattle on start up as the mk2 versions were spring loaded and not activated by engine oil pressure.
For peace of mind you'll need to have the mk3 metal bodied tensioners fitted. Cost is around £400 all in but it's an easy enough DIY with tools hired from the JEC.
You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
Apart from that? Check the floorpan and front V mounts very carefully for corrosion, look for evidence of stonechips on the nose - if none suspect a respray - look very carefully at the front tyres for any evidence of uneven wear indicating suspension misalignment, make sure the gearbox does not engage drive with a thump or any hestation and is smooth and silent in operation. Make sure there's absolutely no evidence of overheating or low engine oil level. Both are V8 killers and you can't just rely on the engine temperatue gauge either. As a minimum you'll need to see a FSH with no overextended intervalls between oil changes. If you buy a convertable have the actuating oil changed for the later spec type.
Parts are mostly reasonable, tyres are not, especially on larger rims which IMO ruin the ride quality and introduce all sorts of harshness and drivability problems you can easily live without. Expect around 28MPG on a gentle run and high teens to 22 or so round town.
Ideally you'd be looking at buying an enthusiasts car that's really been looked after. That might mean a private sale and a lot of time and miles looking rather than buying a tired example from a dealer. Have a look on carsandclassics, jagads and join the JEC to get access to the club classifieds as well as looking in Jaguar World magazine.
Nicasil failure is indicated by a reluctance to start, lumpy idle and the presence of engine oil in the induction system - it's classic loss of compression leading to excess pressurisation of the crankcase. If you're worried you can have a blow by test done, and should see less than 25l/m on a healthy engine.
Jaguar heavily revised the V8 alongside the intorduction of steel liners and introduced a different throttle body and waterpump - both of which had caused grief on earlier cars. Throttle bodies should have been changed under recall which has only recently been withdrawn, the plastic impellors on early water pumps fell off leading to overheating and thremostats occasionally failed too. The secondary timing chain tensioners were revised with another plastic bodied design which also failed over time with the disadvntage you'd not get the early warning rattle on start up as the mk2 versions were spring loaded and not activated by engine oil pressure.
For peace of mind you'll need to have the mk3 metal bodied tensioners fitted. Cost is around £400 all in but it's an easy enough DIY with tools hired from the JEC.
You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
Apart from that? Check the floorpan and front V mounts very carefully for corrosion, look for evidence of stonechips on the nose - if none suspect a respray - look very carefully at the front tyres for any evidence of uneven wear indicating suspension misalignment, make sure the gearbox does not engage drive with a thump or any hestation and is smooth and silent in operation. Make sure there's absolutely no evidence of overheating or low engine oil level. Both are V8 killers and you can't just rely on the engine temperatue gauge either. As a minimum you'll need to see a FSH with no overextended intervalls between oil changes. If you buy a convertable have the actuating oil changed for the later spec type.
Parts are mostly reasonable, tyres are not, especially on larger rims which IMO ruin the ride quality and introduce all sorts of harshness and drivability problems you can easily live without. Expect around 28MPG on a gentle run and high teens to 22 or so round town.
Ideally you'd be looking at buying an enthusiasts car that's really been looked after. That might mean a private sale and a lot of time and miles looking rather than buying a tired example from a dealer. Have a look on carsandclassics, jagads and join the JEC to get access to the club classifieds as well as looking in Jaguar World magazine.
Jaguar steve said:
For peace of mind you'll need to have the mk3 metal bodied tensioners fitted. Cost is around £400 all in but it's an easy enough DIY with tools hired from the JEC.
You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
I agree with everything Steve says, he is more qualified to answer than me, but....You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
Most DIY'ers like me (ive built 2 kit cars) wont be able to do it, its just that bit too complex & deep in the engine block. I'm sure the top 10% of diy enthusiasts could do it, but i couldnt.
Also the XKR gearbox does not run on Dexron III originally, but i understand its a cheaper replacement for the Mercedes Benz/Jag stuff so will still work.
xkrGiles said:
Jaguar steve said:
For peace of mind you'll need to have the mk3 metal bodied tensioners fitted. Cost is around £400 all in but it's an easy enough DIY with tools hired from the JEC.
You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
I agree with everything Steve says, he is more qualified to answer than me, but....You'll also need to have the sealed for life gearbox oil changed every 50k or so - otherwise sooner or later the gearbox will fail due to lubrication breakdown. It's not the simple job you might expect and the specalist oil is expensive too. The XKR has a different gearbox filled with Dexron 111 which is cheaper but the same difficulty applies.
Most DIY'ers like me (ive built 2 kit cars) wont be able to do it, its just that bit too complex & deep in the engine block. I'm sure the top 10% of diy enthusiasts could do it, but i couldnt.
Also the XKR gearbox does not run on Dexron III originally, but i understand its a cheaper replacement for the Mercedes Benz/Jag stuff so will still work.
Dexron 111 is the original specification oil for the MB 'box in the supercharged cars (JEC, Opie Oils and JTIS all confirm this) but the ZF box fitted to the n/a 3.2 and 4.0 V8s must have Esso LT71141. Substuting Dexron 111 for the Esso oil in the ZF box has been covered extensively - you'll understand why when you find out Jaguar charge £23+VAT a litre for the Esso oil - and the general consensus is it will work but is likly to cause shift quality problems and accelerate degeneration of seals and other components. Esso LT71141 oil can be bought for around £8/litre from specalist suppliers like TR Achem so IMO it's just not worth the risk to save a few quid.
Apparently - I've not confirmed this - LT71141 is also sold as Lifeguard Fluid 5 which goes into most Peugeot autoboxes.
Edited by Jaguar steve on Wednesday 14th September 22:06
It's false economy just to do the secondary tensioner, the chain guides suffer pretty bad, I have seen them with just the metal left and all the plastic broken away, must admit you don't get much problem with primary tensioners I have only ever seen one of them crack.
There's always the 'American way' as I call it, they cable tie the chains to the sprockets and undo the cam caps, no need for tools, dont like the idea myself but quite a few have done it that way with good and bad results, there has been the odd broken cam shaft!
There's always the 'American way' as I call it, they cable tie the chains to the sprockets and undo the cam caps, no need for tools, dont like the idea myself but quite a few have done it that way with good and bad results, there has been the odd broken cam shaft!
Edited by XKRacer on Thursday 15th September 08:47
xkrGiles said:
Underneath front footwell outer corners have plates on that can rust through, look underneath & poke with a screwdriver, its a £400 welding job to remove & fix.
Engine cam chain tensioners are made of plastic and can be known to break up, thus causing chains to jump and bent valves etc. Tensioners are regularly replaced for mk3 metal ones, ask the question, budget 1000 or take the risk.
Your advice is spot on. I respect and admire Steve's advice, but haven't personally got the balls or the skill to try it. In that case, who will change your TCT's for £1000 never mind £400, and who would you recommend for footwell welding at £400? I also think you will struggle to find exactly what you are looking for on xkec.co.uk.Engine cam chain tensioners are made of plastic and can be known to break up, thus causing chains to jump and bent valves etc. Tensioners are regularly replaced for mk3 metal ones, ask the question, budget 1000 or take the risk.
Incidentally, under the car there are a number of small circular holes filled with metal grommets. Anyone know what they are, and if they are rusty, can they be replaced?
If your 4.0 is running well now, forget Nikasil, but look after the other stuff. Lots of Jags, BMW's and other cars had it, particularly ones that had low mileages and just a few mile commute most days. There is a moral there somewhere. Sulphur was also very geographically specific, and buying the cheapest fuel from supermarkets didn't help. Another moral.
I would so prefer an XK8/R to an XJS.
Edited by cardigankid on Thursday 15th September 09:27
XKRacer said:
It's false economy just to do the secondary tensioner, the chain guides suffer pretty bad, I have seen them with just the metal left and all the plastic broken away, must admit you don't get much problem with primary tensioners I have only ever seen one of them crack.
There's always the 'American way' as I call it, they cable tie the chains to the sprockets and undo the cam caps, no need for tools, dont like the idea myself but quite a few have done it that way with good and bad results, there has been the odd broken cam shaft!
You're right to raise this but there's two different failure paths to consider. The first is degeneration of the plastic tensioner body alone . In my case at 60k with FSH I did a precautionary tensioner change on my own car and checked all the timing gear. Everything was bright, clean and there was no indication of any wear on any of the chain slippers - however both secondary tensioner bodies had cracked in the same place and one of them was so badly damaged it literally fell apart when I took it off. I'm not alone in finding this at quite modest mileages and 40k later consider changing just the secondary tensioners under these circumstances quite reasonable. There's always the 'American way' as I call it, they cable tie the chains to the sprockets and undo the cam caps, no need for tools, dont like the idea myself but quite a few have done it that way with good and bad results, there has been the odd broken cam shaft!
Edited by XKRacer on Thursday 15th September 08:47
There's a justification for changing all the timing gear of course if any excess wear is found - that's the second path. All the pictures and discriptions I've seen of this much bigger job being done have shown one thing in common - all the engine internals are absolutely filthy with a build up of brown deposits everywhere. That's indicative of lack of oil changing which in turn has contributed to excess wear and embrittlement of the multitude of plastic components surrounding the chains.
Going the American way is risky I agree. It can be done but I'd much prefer the opportunity to get the valve timing back to spot on which you can do with the correct tools as you can compensate for any wear in the the chains by locking everything up and momentariarly releasing all the sprockets and re tightening.
Hello
Steve - I lost you when you started speaking japanese, something about sprockets, cams and chains !!!!?????
Personally I'm not good enough to do it.
Steve - If Dexron is the original oil, why do DesignXKR say they can change oil to dexron3 or pay more for original jaguar oil ? if that was dexron3, then it doesnt make sense. I beleived it was a different oil that was jag/MB original.
DesignXKR near Andover will do TCT for £1000 - higly recommended
Phoenix coachworks did my footwells extremely well, they renovate classics or build kit cars and have 3 levels of job and price - recommended for bodywork
Steve - I lost you when you started speaking japanese, something about sprockets, cams and chains !!!!?????
Personally I'm not good enough to do it.
Steve - If Dexron is the original oil, why do DesignXKR say they can change oil to dexron3 or pay more for original jaguar oil ? if that was dexron3, then it doesnt make sense. I beleived it was a different oil that was jag/MB original.
DesignXKR near Andover will do TCT for £1000 - higly recommended
Phoenix coachworks did my footwells extremely well, they renovate classics or build kit cars and have 3 levels of job and price - recommended for bodywork
Edited by xkrGiles on Thursday 15th September 20:22
xkrGiles said:
Hello
Steve - I lost you when you started speaking japanese, something about sprockets, cams and chains !!!!?????
Personally I'm not good enough to do it.
Steve - If Dexron is the original oil, why do DesignXKR say they can change oil to dexron3 or pay more for original jaguar oil ? if that was dexron3, then it doesnt make sense. I beleived it was a different oil that was jag/MB original.
DesignXKR near Andover will do TCT for £1000 - higly recommended
Phoenix coachworks did my footwells extremely well, they renovate classics or build kit cars and have 3 levels of job and price - recommended for bodywork
Factory recomendation for the ZF 'box is Esso LT71141 and for the Mercedes 'box in the supercharged cars is Dexron 111. This is confirmed by the Jaguar Enthusiasts'Club, Opie Oils and the Jaguar technicial data.Steve - I lost you when you started speaking japanese, something about sprockets, cams and chains !!!!?????
Personally I'm not good enough to do it.
Steve - If Dexron is the original oil, why do DesignXKR say they can change oil to dexron3 or pay more for original jaguar oil ? if that was dexron3, then it doesnt make sense. I beleived it was a different oil that was jag/MB original.
DesignXKR near Andover will do TCT for £1000 - higly recommended
Phoenix coachworks did my footwells extremely well, they renovate classics or build kit cars and have 3 levels of job and price - recommended for bodywork
Edited by xkrGiles on Thursday 15th September 20:22
You could fill the ZF 'box with Dexron 111 and apparently it has been done. Nobody has commented yet on the actual reality of the long term effect of
using the "wrong" oil but as Esso oil is available if you look for only a couple of quid more per litre than Dexron 111 it's hardly worth the risk IMO. I'd be extremely concerned about mixing two different specification oils - you can never get all the old oil out - and have suspicions that some of the comments regarding shift quality, slip charecteristics and long term risks to seals and other components from people who know a lot more about oil formulations than I do ought to be listened to.
The bottom line is cost - sure, when the only source of Esso oil was Jaguar who charged £23+VAT a litre it's natural enough to look for an alternative. The last case of Esso oil I bought cost me about £7.50 a litre so it's a no brainer which oil to use. And, of course you're buying peace of mind too if you use the right product.
cardigankid said:
Your advice is spot on. I respect and admire Steve's advice, but haven't personally got the balls or the skill to try it. In that case, who will change your TCT's for £1000 never mind £400, and who would you recommend for footwell welding at £400? I also think you will struggle to find exactly what you are looking for on xkec.co.uk.
Incidentally, under the car there are a number of small circular holes filled with metal grommets. Anyone know what they are, and if they are rusty, can they be replaced?
If your 4.0 is running well now, forget Nikasil, but look after the other stuff. Lots of Jags, BMW's and other cars had it, particularly ones that had low mileages and just a few mile commute most days. There is a moral there somewhere. Sulphur was also very geographically specific, and buying the cheapest fuel from supermarkets didn't help. Another moral.
I would so prefer an XK8/R to an XJS.
As XKRGiles said we do the TCT for £950+vat. We also do footwell welding at £150 per side.Incidentally, under the car there are a number of small circular holes filled with metal grommets. Anyone know what they are, and if they are rusty, can they be replaced?
If your 4.0 is running well now, forget Nikasil, but look after the other stuff. Lots of Jags, BMW's and other cars had it, particularly ones that had low mileages and just a few mile commute most days. There is a moral there somewhere. Sulphur was also very geographically specific, and buying the cheapest fuel from supermarkets didn't help. Another moral.
I would so prefer an XK8/R to an XJS.
Edited by cardigankid on Thursday 15th September 09:27
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