BMW timing chains

Are you sure that referred to your particular model?

My E39 528 petrol did over 200,000 before I got rid. Original chains, etc.

The V8 versions were prone to the tensioners failing.

I dunno nothing about the 530d, but there *were* a lot of terminal cam chain failures with the N47 engine fitted to these models:

118d 120d 123d 318d 320d 520d

So Beemers were certainly not infallible.

Sort of makes my point. They are all four cylinder models. The 530d a 6.

You need to Google on the actual engine type, which I think may be M47. And read any posts carefully. Lots say an engine is prone to such and such based on the experience of one. A decent forum may have gathered actual statistics.

It is always worth remembering forums can be skewed; people go there with a problem. If you read a few years ago about the VW 6-speed DSG box and the PD 2.0 diesel, you'd swear all the boxes died irrepairably at

70k miles and every cylinder head was a porous casting, when in fact, the boxes rarely fail and only and handful of heads were porous.

Quite. Many forums are full of those who couldn't even change a wheel. But are 'experts' when it comes to faults they've read about.

A decent forum might well just have collated data. Not going to be 100% accurate, but better than rumour only.

The other factor is maintenance, or lack of it. Unless you know the history of a car, it is difficult to be sure the oil has been changed etc., let alone for the right type.

Could be - although I'm not sure poor maintenance would result in timing chain failure before something else in the engine.

It's a very valid point, though. Most on these sort of forums will have bought the car used. Hence going there for advice when a chain or whatever breaks. If the car was new, they'd go to their dealer. So can have no true knowledge about how the car was treated before. Even with FSH.

A timing chain has a lot of surfaces which need lubrication, both within its structure and where it engages with the several gears etc. Sometimes people say chains ?stretch? but AFAIUI the issue is wear and the engagement becoming sloppy, it just appears the chain is longer.

Admittedly, other parts will wear - not just the chain. It comes down to what gives first,

Chain stretch isn't physical stretch of the links. It's slop in the pin and roller joints between the links.

A run of the chain is placed along the edge of a rule and then pulled to extend it. The difference between the actual length between a number of pin joints (eg 10) and the nominal 10xpitch length is the amount of "stretch".

Thank you for confirming/clarifying- I didn?t think the chain actually stretched in the normal sense.

I don?t delve into engines these days, a mix of buying new cars and dexterity issues, but I maintain a interest and do basic things.

On the other hand, I have done around 180k miles in cars fitted with that engine in the last 7 years (120d and 520d).

I had no warranty claims of any kind for either - but have had the EGR recall done on the latest one.

It's a very good engine (and you missed the 25d variant, too) - I certainly wouldn't rule out a car with it fitted.

When you make lots of anything, there are bound to be failures. Sooner or later. We generally read lots from those complaining of a failure, but rarely from anyone saying things are just fine.

If you Google Porsche, you'd never buy one. Intermediate shaft bearing failure. Everyone knows about it. More difficult to find a first hand report of it doing so, though. Plenty saying they've had it changed just in case. But then mainly in the US. Where if you don't change the oil every 3000 miles, no engine lasts. ;-)

I do often feel I'm living dangerously with a 986 Boxster 3.2S, though!

;-)