Good Evening,

At what mileage should the timing chain be replaced on a 2015 Mini Cooper S?

Thank you,
Bob

 

Chains are generally a "lifetime" part, there may be a way to measure stretch (back in my VW/Audi days we could use the factory com tool, VAGCOM to check for it) but that was a unique case for a particular run of chains they made.

 

there are 2 different ones, the actual timing valve chain for DOHC & the timing belt that's not actually for timing, it's for accessories. somebody on here will explain I'm sure. I think the chains = no need but the belts are different.and do need to be changed. the interval is a mystery to me so I too would like to hear the general consensus. I also have a 2015 MCS. F-56 w/ 47K mi.

 

Pretty sure the BMW engineers think the timing chain on the 3rd gen Mini engines never need replacing - The chain is located between the engine and transmission….

 

On the B36 / B38 / B46 / B48 there is only one belt -- the serpentine belt that runs the alternator, water pump, & A/C condenser, and it is not a timing belt. It has no role in engine timing (camshafts yadda yadda yadda) at all. None.

As far as interval on that belt goes, I changed mine on general principle when it had just under 7 years and 108.5k miles on it -- and frankly, it was still in decent condition. Probably could have made it to 120k but I wasn't about to fight with getting the belt off my B46 engine again. With a 4-banger stuffed in that engine bay it is a *royal* pain in the *** to remove or install.

I will note that harmonic balancer separation well before the belt goes bad on its own looks like a real and common-ish scenario, and if the balancer is not dealt with soon enough, it will damage the belt (and via belt wobble, damage other pulleys and whatever components they're attached to). Outside of us gearheads I doubt anyone proactively checks their harmonic balancer -- which in turn makes me expect to see more people replacing balancer-damaged belts than replacing a belt due to it actually hitting the end of its useful life.

The chain, yep, it's inside the back of the engine (not vehicle back, *engine* back -- as in closest to the transmission). Same general location as in the Gen1 and Gen2 engines.

Both Gen1 and Gen2 engines (*not* the B series) are known for having to deal with (1) chain stretch and (2) replacing the plastic chain guides before or when or after they go brittle and break/disintegrate/you get the idea. For Gen3 I don't see much chatter out here, but I suspect part of that is the Gen3 engines are still pretty young. And with them being so young, a change/maintenance interval for the chain may not, as a practical matter, be known yet.

 

IIRC the accessory belt is somewhere between 40-50K. I just changed mine at 42K with a kevlar belted one.

 

Kevlar!! Wish I had thought of that - smart.

 

Yep, we have them here: https://www.ecstuning.com/b-ecs-part...lt/6pk1715ecs/