QUESTION: BMW N47 Timing Chain Problem
Hi John, I enjoy you sessions on Radio 2UE. I have a BMW 123d 2010 with just under 60,000km on the clock. It has the N47 engine. It's been a great car for me so far. After a recent service my mechanic told me he thinks the timing chain is getting noisy and drew my attention to some stuff on the web about the chains snapping leading to expensive repairs.
My 123d is being looked at by BMW shortly. I am wondering if you know about this problem? It seems to hinge around the timing chain being put at the rear of the engine with the intention that it would not need to be replaced.
I am wondering if the same design issues are there for the 3.00 BMW diesel? Have you heard of any significant issues with that engine or alternatively the 2.5 BMW petrol? Thanks for your time and opinion, James
I think yours is an N47 BMW engine. It’s a global reliability disgrace. (Ultimate driving machine - yeah, right…) The fact is, BMW, Mercedes-Benz and Audi are in a race to the bottom - at least with their cheap cars. They're more concerned about competing with the Japanese on price than they are about being true to their brand.
Every time you need to work on a BMW, compared with a Japanese car, you just move the decimal point one place to the right. We had a caller the other day on Radio 2UE: quoted $2400 to fix a wing mirror that had stopped folding in automatically in a BMW X5. And I had an associate tell me about his $12,000 quote to replace the transmission in his BMW X5… It’s systematic - like, you’re in the service department, so grab your ankles, and if you’d like lubricant with that, it’s extra.
You need to listen to your mechanic - if the timing chain breaks the chances are a piston (or pistons) will hit the valves, and the engine will essentially be destroyed. We engineers use the term ‘catastrophic failure’ - that’s exactly what will occur.
Timing chains wear out. They need replacing. This is true of every engine - it’s just a matter of time. They’re generally something of a weak link. However, there’s no particular responsibility on BMW to assist you with this or fix it under warranty. (They might choose to do so.)
Certainly the reports I've read - mainly from the UK's BBC - indicate that BMW has been less than supportive to customers who've had the timing chain break. To me this is a typically disgraceful corporate position to take. You have to understand the out-of-control corporate hubris in the boardroom of the top three German carmakers. The money is nothing - but admitting there's a problem is absolutely verboten.
What the UK's BBC Reported
At 60,000km it will be difficult for you to prove premature wear. (Wear and tear is not covered by warranty.) I wonder: Is there a timing chain replacement interval in the service schedule? If the service history on your car is good, then you might have a case if the replacement interval is, say, 160,000km. BMW is absolutely aware of this problem, because it’s been widely reported, but like all premium brands they sweep it under the rug lest it tarnish the perception that motivates people to buy the vehicle. They’re in the business of selling cars, not keeping them going cost-effectively.
I don’t know what BMW Australia’s attitude to the problem is (in terms of customer support) but the engineers in Munich who elected to put the timing chain in the rear of the engine - which requires the complete removal of the engine from the vehicle to replace the chain - should hang their heads in shame. I wouldn’t expect a sham like that from Great Wall - but there is probably some completely obtuse engineering justification for doing it this way, perhaps compactness or ease of proliferating the engine across multiple vehicle models. I don’t think it’s a statement from those engineers that the chain should last for ever (ie: life of engine). If it were, they got the R&D on that chain badly wrong.
For future reference: unless you have $100k to spend on a car, a Mercedes-Benz, BMW or Audi is a kind of over-priced automotive fraud. Like - here’s the badge, but the engineering excellence isn’t included, and neither are the features youd expect in a true premium car. You’re always - mark that word: ‘always’ - better off in a Japanese car. Sorry to be the bearer of bad tidings. The new Mazda3 diesel would murder the 1-Series diesel against all objective criteria.
The reliability & service costs are just as bad (worse, in the case of service costs) over $100k - it’s just that, over this price, you actually do get premium features, and if you’ve got $100k+ to drop on a car, then you probably won’t need a defibrillator when a five-figure repair bill hits.
I’ve had a lot of exchanges with owners of these cheap German cars in situations like these. It’s why I’m such an advocate for not buying them in the first place.
I hope yours is a happy outcome. Let me know.