High mileage N47 without problems (120D, 320D, 520D etc)

[Lowtimer]

Morning, all

We hear a lot about N47 cam chain problems but as with the infamous Porsche RMS failures, you never hear about the majority that keep on running fine. So it always it is hard to know the proportion of cars affected.

So who's got an N47 powered car that is running fine at high mileage? My 57-plate 320D Touring manual is just passing the 100,000 mile barrier and sounds just fine. I've had it since it came out of the BMW UK fleet at 7000 miles. I've always had the oil changed at around 10,000 miles rather than the full service interval, but apart from that is treated like any other old shed, thrashed mercilessly around the Dales and Yorkshire moors, and for high speed commuting up and down the motorway network.

I'm sure there are many higher mileage cars out there with the N47 engine and would like to hear about them. The cars with the engine are:
- All 1-series diesel after the March 2007 facelift
- All 3-series four-cylinder diesel from the 2008 facelift
- All 520D after September 2007 build.
- X1 and X3 diesel four-pots from, I believe, some time in 2008 onwards.

Over to you...

[Lowtimer]

So your timing chain is fine. What is the current mileage on the engine?

[Lowtimer]

smashy said:

From the research Ive done I wouldnt go anywhere near these 2ltr diesel engines in your chosen cars

What research have you done?

That's why I am asking the question about timing chains. "Everyone knows" on the internet that every N47 blows up, because there are people complaining about it happening to them. Yet I am only actually aware of about 45 documented cases, and yet around half a million new N47 engined cars have been sold in the UK since 2008. So what's the actual risk? Naturally, people who are having problems self-select as the dominant contributors on "My BMW has blown up" threads so it's in no way a representative sample.

And when I do what little research I can in the wider world, when I see an N47 engined car parking next to me at the supermarket or the petrol station, every time I ask how it's going and if they've had the cam chain problem. And everyone I've spoken to in the last year has said "no problem".

[Lowtimer]

One the old 1-series, the N47 engine was from March 2007 production on, the facelift cars with revised bumpers. This includes all coupes, convertibles and 3-door models. Before the facelift only the 5-door hatch was available.

[Lowtimer]

HoagieLomax said:

Seen two instances of snappage on 2007 N47,one at 125k miles and one at 140k.Also seen noisy ones at 80k and 150k and some with a slight noise at 50k.

Having said this,I have also had two broken chains on M57 TU2 engines which were at lowish mileage 60-70k and this engine is not really known for chain issues.

Buy with your ears open!

Thank, but I already know there are some broken ones. As you evidently see lots of cars with these engines let me put it this way: how many unbroken ones over, say, 50,000 miles and 100,000 miles have you seen?

[Lowtimer]

HoagieLomax said:

If we are talking about the majority of faulty engines 07/57/08 I would say it's 50/50,the fact remains that there is an awful lot of duffers out there and I wouldn't advise one in that year.

Not sure I understand. Are you are saying that half the total population of cars in your area in that age band have had engine failures? Or is that a skewed sample, i.e. based purely on cars which have been brought to you with engine problems?

[Lowtimer]

smashy said:

Lowtimer ,serious q as a follower of your thread.Your going to get one of these arent you.I reckon.

Your looking for reasons to buy one not ,not to buy one.But when your driving one arent you going to be constantly thinking "when is it going to go".
Do you do a lot of miles,I do and getting towed from the M42 to chiswick west london at ten oclock at night after waiting 2 hours on the hard shoulder ,is NOT funny.Never mind the big bill coming....that was the other problem the Turbo

Dont do it. Get a 3 ltr if you must!!Your safe then.

Edited by smashy on Saturday 28th September 00:11

No... if you read my first post you will see that I have just come up to 100,000 miles driving one. It's never missed a beat or made any untoward noises. The same is true of all the other N47 owners I've actually met face to face. What I'm interested in is that there seems to be no connection at all between 'internet life' and 'real life' i.e. my first-hand experience and that of people in the wider world who I meet, versus what is reported on the internet which is the idea that they all blow up.

The risk of it cam chain failure obviously exists. The chance of me winning £1m on the lottery also exists. But if one only hears from the people who've had it happen, it makes a (maybe) one in 10,000 risk feel like a certainty.

Meanwhile, if it goes, it goes. In the last 33 years of driving, I've only experienced two engine failures while the car is in motion, which have forced me to stop at the side of the road. One of those was a 9 month old Honda Accord 2.2 CDTI which switched itself off in mid overtake - presumably a mysterious electronic fault, cleared itself after recovery, no fault found by dealer.
One was a sheared distributor drive shaft on a Vauxhall Chevette.

Edited by Lowtimer on Saturday 28th September 10:48

[Lowtimer]

No, I'm going to keep it.

[Lowtimer]

va1o said:

You could just get an aftermarket warranty. I've heard good things about the official BMW warranty and it should pick up any failures. Costs you a bit now but it gives you peace of mind.

I could, but over the last 10 years or so I've found it cheaper over time to self-insure and just keep an emergency fund invested case it's needed. Most insurance companies aren't really interested in providing warranties in things past 100K anyway. It'd only take a month or so to get the engine rebuilt and although this is the main daily driver I have other cars I can use if I need them.

There's one here that's just sold with 212,000 miles on it...
http://www.pistonheads.com/classifieds/used-cars/b...
... and I really can't see any reason why mine won't be still going in another five years' time.

Edited by Lowtimer on Saturday 28th September 14:08

[Lowtimer]

va1o said:

Fair enough I guess that approach works too, but have to bear in mind a rebuild would run well into 4 figures.

Not a problem. The depreciation on a new one would be much more. And I simply don't believe it's more than a few per cent chance of failure. Whereas the depreciation is an absolute total 100% certainty.

va1o said:

How do you know it hasn't already had the chain fail and engine rebuilt?

I don't, but why do you think it has? You seem to be asserting that every single BMW N47 either has or will blow up. There aren't half a million out there that have had the engines rebuilt. As I said I've only been able to find a two-digit number, which is really hardly any in the greater scheme of things.

As someone else said above, we had exactly this sort of internet-based excitement in the Porsche world with the 996 / Boxster water-cooled flat-six engines and their intermediate shafts. That was another case where "everyone knew" that they were all ticking time bomb, but the premature failure rate on those some years later has turned out to be in the single digits, percentage-wise, probably something in the rough area of 5%. Enough to make an absolutely huge, massive tidal wave amount of internet complaints, but still a 19 in 20 chance that any individual one was fine.

Edited by Lowtimer on Saturday 28th September 18:55

[Lowtimer]

Good, specific factual data: thanks.

Interesting that both 2012s have done it, and at low mileage too, whereas both your high mileage older cars were OK.

Given that you have the same drivers, and (I imagine) very similar types of usage for all four cars, that rather suggests that some element of the design changes made for the later production may actually have made things worse rather than better.

[Lowtimer]

smashy said:

Dont do it. Get a 3 ltr if you must!!Your safe then.

Edited by smashy on Saturday 28th September 00:11

Having looking into it some more, it turns out you aren't any safer with a 3.0 diesel than with a 2.0. A bit of googling shows that the 3.0 litre N57 engine has exactly the same rear mounted cam chain, and exactly the same wear / failure issues, as the 2.0 litre N47. It is less well publicised than the N57 issues because they sell something like 20 four-cylinder diesels for every six-cylinder diesels 3.0, so there are that many more four-pots out there.

Mind you, over on General Gassing today there's a bloke with a 3.2 litre Audi that's done exactly the same thing, and I was surprised to find that's a rear-mounted cam chain too.
http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[Lowtimer]

No, that's the previous engine. Yours is the one where the swirl flaps are supposed to be the guaranteed blow-up

[Lowtimer]

farbbm said:

IT1GTR said:

223k still going strong

What model and age of BM have you got IT1GTR?

According to his profile, a petrol Mitsubishi

[Lowtimer]

No, that's the 'swirl flap' one too, like the 2006 520D a few posts up. Still, good for you, glad it's going strong.

[Lowtimer]

Yes, I think that's pretty much where I am on this.

I've always done premature oil changes as I don't think anything over 10,000 miles interval is sensible, so I'm planning to push on for at least another two or three years, say 160,000 miles, and see what the car feels like then. I do stay on top of it mechanically so at its current 100,000 miles it drives beautifully and the interior is still fresh, so really all it needs at the moment is a new windscreen: the current one is fairly hazy with tiny abrasions.

[Lowtimer]

Good point about the stop-start. I've always disabled that on starting the engine, partly out of mechanical sympathy and partly because I find it intensely annoying.

[Lowtimer]

As the OP, and in case anyone's out there waiting for my N47 to go bang, I'm going to have to disappoint you. Having had the opportunity in the spring to buy a fairly rare E39 530i Touring with manual transmission, I scooped that up, had some fairly heavy mechanichal refurb work done on it, and then once it the 530i was running as I wanted it, I flogged the E91 320d dag-dag. It was running very well when I parted with it. Can't remember the exact mileage but I guess it was about 110k, so I have more than 100K of personal mileage out of it.

[Lowtimer]

If you really want to carry on driving a 318D Sport then the big advantage of that one is you know exactly where it's been, and what's happened to it and how it's been looked after since new.

Once I've committed to a car I definitely like to get a lot of use out of them, but personally after I've done about 100K in a car I'm ready for a change.

But for you, you obviously really like that particular car, so I'd say it's probably a reasonable deal, better than buying a different example of the same type purely because of the known history, which takes a lot of the usual used-car risk out of things.

[Lowtimer]

My experience with big corporate fleet disposals is that they are not really interested in counter-offers: they dispose of lots of cars all the time and have an extremely good idea of what they will be able to get for a car, and will have quoted you accordingly. In fact they may already have a trade buyer for it on the basis of them saving the refurb or prep costs that they would do before moving it on to you. So you can try chipping them down but I wouldn't expect much, and they might just tell you to cough up or lump it. Offer to take the car as it stands, that might save you a few hundred at least.