Hey folks, I need you opinion,

About a year and a half ago I got the timing chain guiderails and tensioner replaced on my 03' R53. Since then I've had off and on what sounded like timing chain chatter that I've brought up to the local MINI dealer during routine checks and maintenance and they've assured me is fine and they didn't find anything wrong.

Last fall the car blew a head gasket. I decided to go ahead and get it replaced after having them do an inspection on the health of the rest of the engine and they deemed it to be in good enough shape. At this point I once again brought up the intermittent chatter. They stated they'd check it with the engine apart. The head was machined improperly and ended up being covered under warranty. I, once again, was told the timing chain and guides were fine and they weren't sure where the intermittent chatter was coming from. It was suggested that perhaps that the cat had failed and juggling around shards. Which didn't sound quite right to me. But other than the guides failing again, I couldn't think of anything else so it was the best guess I had and planned to get it replaced.

Fast forward to a couple of weeks ago. The car stalled out on me and upon attempting to start it sounded like the chain had gave out. Had it towed to the dealer and they confirmed the chain had indeed failed and damaged the bottom half of the engine in the process. They insisted that the chain had just given out "for no apparent reason... which is pretty unheard of on this model". I asked about the condition of the rails and they stated "they were damaged, but it probably happened when the chain broke".

I feel like that its highly unlikely that the chain would fail at 120k miles without the guides and/or tensioner going first. And figured I should at least do research before being out of a bottom half. Has anyone dealt with anything similar? Anyone else have a R53 chain spontaneously jump and give without something else in the case failing prior? Any other info on this?

 

We actually see the chains on the Gen 1 cars tend to stretch somewhere between 120-150k miles. So we will replace them if doing other work or if it starts to make noise of any kind. The issue is the noise is the stretched chain actually slapping back and forth which usually breaks the guide and will show wear on the block as it moves around. If you post pics I can evaluate it more, but yes we see them stretch at this mileage.