2004 R53 with 120,000 miles. I have what seems to be a severe timing chain rattle. I replaced the tensioner which made no difference. Does this point to replacing the guides? Or should I change the chain as well?

thanks

 

Yes, you do the whole thing. Guides and chain with that mileage.

DIY: https://www.northamericanmotoring.co...placement.html

https://www.ecstuning.com/Mini-2004-...Engine/Timing/ Tools and parts listed. Do the oil change after you are done.

 

Before you tear the front of the motor apart watch below (again?) - did you make sure the plunger was pushed in on the tensioner before installing it? And, in case you got an 'offshore procured' cheapie from CRAPA or Pep Girls, might be worth a 2nd try with a known quality replacement to make extra sure:
https://www.fcpeuro.com/Mini-parts/C...in%20tensioner

 

Although I've never done a timing chain - All holds true with respect to all replacement parts and the comment below >
+1
+1

 

Before you dig into the timing chain check the belt tensioner. It contains a black pneumatic rod (like a tiny hood opener) that is attached with two bolts. The rod has plastic bushings on both ends that dry, crack and fall out over time. The rod then vibrates against the bolts at both ends and sounds just like a timing chain rattle. You can access it easily by removing the passenger side wheel and fender liner. A new rod is only around $25 (partsgeek.com) and is easily replaceable.

 

Thanks for all the input. Belt tensioner has less than 10K miles on it, but I'll check it. Chain tensioner was compressed when installed. I pulled it back out, checked it and reinstalled it, no change. (it was from Pelican Parts so I assume it was decent. I bought another from ECS just in case, but not here yet). Should the tensioner feel smooth when compressed? both the old and replacement unit are sticky about half way through the stroke. I'm taking ECS's advice and changing the chain and guides anyway because of the mileage as soon as they get here. Can the chain stretch so much that the tensioner won't work?

Here2Go-neither of your links work.

 

So, I now have a nice new timing chain and tensioner (don't ask why I didn't do that when I replaced the timing cover gasket ). Still had a horrendous rattle. Turns out the pulley on my (fairly new bosch) alternator was really loose. Tightened with loctite and problem solved. Hopefully that's it for a while. I'm getting really good at putting this car in front end service mode.

Just to make things more interesting, while this car was on jackstands waiting for parts, my "new" car (2010 Toyota Venza) needed a new axle, one front and one rear wheel bearing, so I was down to my two most reliable vehicles, a 1974 Triumph TR6 roadster, and 1973 Triumph Bonneville