2006 40,000 mile diesel engine blow up

[barrywi]

Just had a call from a member whose 2006 XJ diesel engine has blown up at 40,000 miles. No details yet as to why as the engine is not disassembled but needless to say he is not amused. He has put it in the hands of an independant as all Jaguar suggested was to take it to a main dealer and as he has a good insurance to pay for a new engine( he HAS checked) and he did not want to have Jaguar remove the engine because of extra cost.
I am posting on his behalf to ask if any other members have had a similar experience, it seems extremely low miles to me for such a catastrophe unless other factors are the cause.

[PaulGover]

Blow up? An explosion seems very unlikely, except within the cylinders, where they're rather common Here's my two pence worth, though I've not suffered anything like this so far.

My guess would be a failed cam belt, which AFAIK leads to bent valves and smashed pistons, and is the most obvious single point of failure. The other failure I've heard of, but less catastrophic, is seized turbos resulting from repeatedly turning the engine off when they're red hot immediately after a thrash down the motorway, thereby baking their lubrication oil.

I presume by "insurance" he means 3rd party warranty, in which case whether he goes to Jaguar dealer or not will be down to the fine print therein. IMHO, if the warranty covers parts and labour, then going to a Jaguar agent is better than third party, but maybe there's a limit on claims.

Even so, going to a Jaguar dealer initially might have been a better course of action: if it is the cam belt, it's a service item with supposedly 100,000 mile life, in which case Jaguar might consider some financial assistance as it shouldn't fail 40% of the way through, but I'd guess they'd be less inclined if it's with a third party.

[robv12]

Barry, give Dave Marks a call, he has done a number of these engines now at circa 40K miles, there was an explanation of the failure at the 350 seminar, but not having a tractor juice 350 I switched off a bit at that point, something to do with turbo seals??, please do not quote me on that though without checking it out first

[jeff1954]

This engine problem could be down to the DPF Filter, as it's only done 40 K maybe it's short journeys and contanimation of the engine oil as covered by Barry's article in January's mag.

Jeff.

[J44EAG]

This oil dilution issue, problems with the turbo actuator valves and the need to replace the cam drive belt AND two complete pulleys at 105k miles is what would worry me most about running a diesel Jaguar. As Rob just said, there are also some issues with the turbo oil seals.

These diesel cars certainly appear not to be for the faint hearted as a DIY maintenance prospect and does it cost heavily when it all goes pear shaped. I doubt that many diesel Jaguar owners would be able to maintain such a complex piece of machinery themselves unless they had full access to the full range of test gear and special tooling.

Servicing costs when compared to running a petrol unit are likely to be larger by some considerable measure. OK , fuel running costs with a diesel are less but in the event of the above issues, I think I would personally be happier paying higher petrol fuel costs than possibly have to face some or all of those problems some time during ownership. EFI petrol engined cars are rather easier to maintain than an EFI diesel.

As to the oil dilution caused by the need to over fuel the combustion process in order to re vitalise the DPF system, leaves me somewhat concerned. To have to actively watch for a rise in engine oil level in case it increases, is enough to give me the screaming hibi gibies. The effect of running an engine with fuel diluted lubrication oil leads to engine bearing failure and the need for an exchange engine. Someone told me the core unit cost around £2800 inc VAT. I`ll stick with changing the odd pair of V8 tensioners!

In principle, the idea of a diesel makes total sense on paper. However it is the cold reality of every day operation, practicality and overall gross economy and that tells me that I`m likely to stay a petrol head for many years yet. I only wish I had the confidence to buy diesel but for me the right buttons have not yet been pushed.

Mike

[jeff1954]

I dont think there is much difference between the two models Mike' as you quite rightly say you have to have the timing belts changed on the diesel, but you have issues with the chains and tentioners on the petrol engine. I am however pleased that mine does not have a DPF Filter as mentioned earlier.

Reference the turbo oil seals, if after prolonged high speeds before you shut the engine down, Jaguar recomeds that you let the engine "Tick Over" for a couple of minutes to let the tubine blades "Cool Down" Hopefully this procedure and regular oil changes will result in long tubo life.

Jeff.

[J44EAG]

Typical turbo cool down procedure really. Oil bake on the turbo bearings results unless the turbo cools down with a good copious flow of cooling oil being pumped through the bearings. If that does not occur, the elevated temperature of the turbo just boils up and bakes static oil into a formation that gradually reduces oil volume through the bearings to a trickle or less. Then the seals and bearings give up and a new or reconditioned unit is needed.

If you have ever run a turbo Sierra Cosworth, you will know this cool down process after a run became second nature to many owners. One learnt very quickly! Self included.

Mike

[barrywi]

Thanks for the help guys, the owner says he will get back to me when it has been sorted and tell us all what the problem was. David Marks has replied to me re the problem but until the member comes back with his email I cannot forward any more help. A recond engine is £2750 and a new one is £3500 but op course if the cause of the problem is a turbocharger or anciliary failure then much more needs to be checked and changed if necessary.
My "tractor" is running fine Rob!( famous last words)

[barrywi]

Simple tip: On the 2.7D V6 jaguar diesel engine DO NOT over fill the engine with oil. Better to have it half way down the dip stick between full and low.
Over filling will cause engine blow up.

[christopherspeed59]

Hi guys, just had my cam belt changed on my diesel S type, cambelt kit from Stratstone Jaguar in Stoke through their ebay shop £50, small local garage who do everything for me charged 5hrs at £35 plus the vat £210, also changed auxillary drive belt while it was apart at a total cost of £229.80 + £50 for the cambelt kit. So its not that expensive if you shop around and find a small local garage you can trust. My car is an 05 and does not have diesel partculate filters so i don't have that problem to worry about at the moment, but i can see the problem arrising next time i change the car as i would probably get a later diesel S or an X350. With regards to turbo cooling even if you came down the motorway at 100mph by the time you come of the slip road and find somewhere to park you will have had a few minute's cooling, it cant be that critical surely?

[J44EAG]

Remember a turbo can run at nearly white hot temperatures. That heat takes some dispersement. Open the bonnet at night to see what I mean.

Yes, you will dissipate some heat as you cool the car down in slower speed driving conditions, but never the less that turbo will remain very hot when you switch off. Idling the car for a couple of minutes will continue to pump oil through the turbo bearings as it cools. If that does not happen, oil bake will occur within the bearings, which chokes not only the bearings with carbonized oil, but tends to block oil galleries which then leads to bearing oil starvation.

Cosworth Sierra turbo cars were notorious for this issue. Owners soon learned that a few minutes running at tick over after a hard run was the only way to prolong turbo life.

Critical action? Yes, I am afraid it is.

Mike

[stuarthardy]

Absolutely right Mike. The turbo continues to run at many tens of thousands of rpm after the engine is switched off and is effectively unlubricated for the time it takes to spin down.

All the technology we have at our fingertips and we still have not come up with an answer to this problem. I have mentioned it to a lot of friends and colleagues and the majority of them seem to think that the maker of THEIR car must have something in place to stop this happening. NO THEY DON'T!

A couple of minutes at idle after a hard run or 20 seconds or so after a period of slow traffic WILL make a big difference to the life of your turbocharger. Its a basic engineering fact.

Regards

[J44EAG]

Just looking at the postings above, I see I`ve said the same thing twice but in different words! Thanks to Stuart for his input also.

Wiki gives a similar viewpoint.

http://en.wikipedia.org/wiki/Turbocharg ... g_lifespan

Mike