3

I was looking to buy a used BMW and realised that the one I liked has timing chain.

I am more used to timing belts and know that they cost about £200 ($320) to replace. However, I don't have any experience in timing chains.

Is it gonna cost me a lot because the car has done around 86000 miles and the owner informed me that he replaced the timing chain a few thousand miles ago.

Your advice is appreciated!

  • 1
    Find out why the chain was replaced. As far as I know, a BMW's timing chain shouldn't generally need replacement anywhere near 86k. – Josh Caswell Oct 1 '14 at 18:46
  • @JoshCaswell Thanks josh....How long after do I need it replaced? Or how dangerous is any issue with timing chain (e.g. becoming lose, getting stuck etc.)? – hagubear Oct 1 '14 at 18:48
  • I don't seem to have spoken clearly. My thought was not that you should worry about replacing it again, but that there may be an important reason, which you need to know about, for the previous owner to have replaced the chain. There's no reason -- again, AFAIK -- under normal usage for him to have needed to do so; thus to my mind it's a suspicious detail in the car's history. There could be other problems that are related but either latent or just plain unfixed. – Josh Caswell Oct 9 '14 at 19:46
5

BMW's plan was for it to never be changed. Looking at some of the forums, I think advice given from this BMW site seems about spot-on:

Well-l-l, I hate to say "never" but the point being, one often needs/wants to crack open & rebuild an engine for other reasons (ring/valve wear, main seals, etc.) by a quarter-million miles or so--at which time, check the chain while you're in there. Otherwise, yeah, effectively lifetime.

And:

Properly lubed, the t-chain and tensioners/guides will last as long as the crank bearings. When the engine is eventually torn down for a rebuild, a chain kit (and crank and cam gears) is part of the job. Until then, be happy we don't have timing belts!

On the forum, the sentiment seems to be there aren't many instances of a broke/slipped chain. They just don't normally fail. I do agree with the @JoshCaswell thought & link above ... preventive maintenance will never serve anybody wrong.

  • The chains themselves are reliable. Plastic chain guides on the other hand... well, let's just say YMMV – Zaid Oct 2 '14 at 10:56
  • 1
    My point in my comment -- which I don't seem to have expressed clearly -- was that there's no inherent reason for the previous owner to have replaced the chain at 86k. Thus, it's indicative of a possible problem, something the purchaser should be aware of and maybe investigate for related issues. – Josh Caswell Oct 9 '14 at 19:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.