Hi everyone,

I've just come into possession of a 2013 Mini Cooper Standard Hatch with 153k km (I believe it's a late R56 model?), with the N16 engine. The car has a loud rattling noise (death rattle?) from which I suspect is timing chain slapping. The noise is present at low revs and will decrease at higher speed, but never goes away completely.


I removed the valve cover to inspect the timing chain but don't see anything that's out of place - chain looks ok, doesn't look loose, guides seem intact. This leads me to believe it might be the tensioner at fault - I tried moving it in and out using a long screwdriver and it seems to move ok, but I know that's not the best test.

Apologies for the heavy breathing, it's really cold where I am and I was also wearing a mask

I just wanted a second opinion on this before I get a replacement tensioner and try to fix it myself (Mechanics are quoting $2k+ to replace the timing chain - assuming that's the problem). I don't have the tools or equipment to check the timing chain/guides etc. Just wanted to see if it's possible to fix myself first.

Would there be anything else that might cause that rattling noise? How easy is it to replace the tensioner - I only have basic tools. I've checked out a lot of videos and posts, but they're mainly for the N12/N14 engines and are mainly related to broken guides.

Many Thanks!

 

That doesn't sound like a timing chain. That sounds like a valve or cylinder issue to me, but hard to tell in a video.

 

Thanks for your reply. Interesting, the noise mainly focused on the left side of the engine which is why I assumed timing chain - I believe the car had burning oil issues as well at some point.

Is there anything I can do to check the valve or cylinders?


Please ignore the metal piece on the 3rd spark plug housing - I forgot to remove it before taking the picture

 

You can do a compression test to see if they are all healthy or not. If not you would want to do a leak down test to see where they aren't healthy.
That sound just doesn't seem like a rattle to me, more of a knock or slapping piston or valve.

 

Hmmm, you might be right. I'm looking up other videos with engine knocking and it sounds very similar. I used an ODB machine and didn't see any misfires on the engine.

If this was the case, would this constitute to an engine replacement?

Thanks for your help

 

It would depend on what is making the noise. Could just need timing adjusted, could be a bent valve, could be a number of things. Won't know until you diagnose it. Start with a compression test and go from there.

 

I have found a video which has a similar sound, the OP says it might be the serpentine belt.


Anyone else might think that's also the case?

 

I had my belt go bad, (pieces were chunking off) but ended up that that was only part of the sound, another portion which was the main issue was the water pump pulley from bumping on the friction pulley had started (started lossely it was worn out) losing little pieces of rubber causing the friction pulley to bump and made a rattling sound. replaced that sound was gone... now im working on a different kind of issue... If you do the belt, for the love of all things, do not trust your box stores to get the right belt... 3 times now 3 different stores have brought me in the wrong belt, assured me it was the correct one and I burn through then in 3months... they tear and rip width off the belt, this time the side that handles my water pump... causing the thermostat housing to superheat and split. (so new one of those, new belt (ordered direct from rockauto)
The belt your looking for is a 6pk905 or 6pk906 (the 6pk900 the one that the "big book" says works... i assure you will only cost you money)

 

Wish I saw your message sooner, I literally just ordered a 6PK900 belt - OEM actually mentions 895, but is superceded by 900, so will see.

Upon another inspection and listening to the source of the noise, I'm fairly certain the noise is coming from outside of the engine on the left side - so now I'm thinking it's the belt. I will get under the car and replace the belt this weekend. If that doesn't fix it, will replace the timing chain tensioner. Just trying to work out how a bad serpentine belt could cause such a noise and why it would go away at high speed hmmm.

 

Look at your water pump pulley... (sorry mines an N14 engine, your belt is likely different! lucky you.) the belt was a small thing compared to the damage to the pulley... (i did all this through the passenger wheel well (us car))
High speed similar to hitting bumps slow vs fast... friction pulley bounces over the rough spots on the pulley thus reduces the sound.

I did notice at speed when I had the issue it was more difficult to hear vs at an idle or slow speed (suspect due to road noise and engine noise)....
The job is a bugger to replace the pulley if you follow the pelican parts how to (service mode) I did mine through the wheel well... can find my write up here R56 - Code U115E displayed after timing chain replacement - Page 2 - North American Motoring

 

Like Jay already said:
Check the belt and waterpump pulley for missing pieces. If you're lucky, it's only the belt. The pulley requires some cursing and "knuckling" to come off but it is doable.

It is (very!) unlikely that the tensioner (or the timing system as such) produces this kind of knocking noise.

 

So good news. It was just the serpentine belt! It took this long as I was misinformed with the tools required for the parts.

Here are my observations:

For the n16 engine, you can use a 30mm box wrench to loosen the tensioning screw (turn clockwise, towards the front of the car) - I was seeing all sorts of different sizes on tutorials and forums, thank god for amazon return policy
You can access and push in the screw for the tension lock from the engine bay, no assistant required - not sure why people insist on going from the bottom
There are some screws that require a T30 bit for undoing the wheel liner. You also don't have the take the entire liner off, just the front part will do
The pull-out tab for the water pump tensioner was really hard to pull out, I had to use pliers with some force to get it to give
I purchased the 6PK896 belt, the original one was a 6PK895. I was super convinced that I had the wrong belt size as it was a pain in the *** to put in
A little bit of WD40 went a long way to putting the new belt on, loop on the AC and the alternator first

Hope this helps anyone that notices a similar sound in the future.

The belt had bits and pieces coming off the treads - just cant work out how it would produce such a noise though

 

I just had the exact same noise and it was in my tension wheel. When I did a water pump, I did not "click" the tab back in and it was loose. Weirdest damn thing I ever saw. I thought the motor was going to blow and it was all in the pulley.

 

Pressing the tension lock button from either below or above is not the issue. Turning the 30mm screw to loosen the tensioner pulley with a regular 30mm wrench from above is only possible after removing the headlights and lock bridge (requiring the head lamps to be adjusted after reassembly). And since replacing the belt requires the wheel and liner to come off anyway, it is no extra work to also loosen the belt tensioner from below (using a "straight-head" wrench).

I replaced mine twice with a 6PK894 twice and had no problem fitting it. I always leave the smallest pulley last to put the belt over (making first sure that it is tight within the grooves of the other pulleys).

IMHO, it is never a good idea to use lubricating agents on belts: they may both introduce slippage and accelerate ageing of the rubber.

 

I have never put my mini into service mode (removing headlights) and I have done timing chain, thermostat housing, serpentine belt... 4 times now (curtesy of Parts tech not knowing how to get the right bloody parts) When I do the belt I have a helper apply pressure to the tensioner to lift it up slightly from the top while I put the belt on from the bottom, putting it on the AC compression last, as I find it to be the easiest one to do.

 

Maybe my post wasn't clear enough:
I do NOT advocate loosening the belt tensioner from above (unless the only wrench/tool at hand does not fit from underneath).

By the way:
Putting an R56 into service mode involves quite a few more steps than just removing the lock bridge and headlights.

 

I gotcha, theres work around for alot of projects, I have avoided going to "service mode" just because of the amount of work it takes, I dont want to do it until I need to!

 

Thread revival. Anyone figure out the root cause here? Have a N16 engine here with the identical noise as both videos above. Removed valve cover, inspected and found no damage or unusual wear. Replaced chain tensioner, zero difference. Sounds to be at about 400RPM frequency so it's top of the engine, not bottom (cam takes one rotation for every two crank rotations). It's a metallic clatter so this seems unlikely to be belt related but let me know if I'm wrong.

 

Are you referring to the OP's issue? If so:
More detail (full post)

I'm asking, because you have already dealt with the issue in the past. So possibly you are referring to something else?

 

Thanks. It was a stretched belt causing the tensioner to clatter into the side of the engine block, presumably. Owner said the belt was new but then remembered that was their other MINI.

My previous post was related to dried out rubber on the water pump friction wheel, which was not making any sound like this at all. The sound for this issue wounded very much like like rod knock or a broken valve lifter. (muffled metallic - not rubber or plastic - therefore surprised that a worn belt could cause such a noise).

Thanks