New timing chain - Engine still noisy - Video links attached
 

Hi all, need some opinions please on engine noise and piston movement in the cylinders, here is the scoop.....

I am helping with an engine repair on a 2007 R56 Cooper S, the timing chain tensioner failed (as do so many) so bought a new kit plus the timing alignment kit, dropped the sump cleaned out all the debris and assembled everything again, it had jumped time so before starting it back up we took some cylinder compression's which were 135, 60, 100, 70. After this suspected there may also be valve damaged but went ahead and started it and it sounded like this:


So decided to pull the head and check for bent valves. After removing the head this evening they seem to be ok (without actually removing all the valves) we pulled the cams off and filled the inlet and exhaust ports with gas and checked for leaking through the valve seats, none of the inlet leaked and two of the exhaust had a little seepage but nothing major, almost negligible; the only other thing is a lot of carbon build-up in the inlet ports but I have heard this is very common. So we decided to look at the pistons, don’t really see much in the way of any contact with valves and there isn’t much of a lip at the top of the cylinder bores but I can move the piston around left to right and top to bottom but what is really more concerning to me is that I can also twist the piston which I am assuming is wrist pin wear. Video of this movement is here:


With the sound of the engine I am thinking this is piston slap and I really need to pull the bottom end and check things out, opinions would be greatly appreciated as I have never seen this kind of movement in past engines that I have built re-built and it seems excessive. In talking to the owner and sending the video to her (after replacing the timing chain) she then said that it actually always had a bit of a diesel rough sound to it!

Thanks!

Austin

it's trash ! total rebuild

Yea, that does not look good at all, I would look into a referb or replacement engine.

Do not take my experience into consideration; however, take Consumer Reports, which coincides with my experience:



Consumer Reports

Cars you’d be foolish to buy

Reliability, satisfaction, and test scores knock out these contenders

Published: April 01, 2015 10:15 AM
Worst used car: Mini Cooper S
When it comes to choosing a used car, you can put the odds on your side by choosing a model that performed well when new and has a great reliability track record. Of course, reliability hiccups can happen with any used car, but the Mini Cooper S has the worst history among all cars we have tracked over the past decade. Sure, the car is cute and delightfully entertaining, but year after year, the likelihood of having a problem that requires a repair is heartbreaking. And among the 17 trouble spots we track, engine major, engine minor, engine cooling, fuel system, body integrity, and body hardware have issues at an alarming rate. Although Consumer Reports often recommends skipping an extended warranty, the Mini Cooper S is a case where the investment would be a good hedge against potential problems.