I want to ask the guys out there with a Mini Cooper S if any have had issues or know of issues with the engines breaking pistons ?
I bought my son one with low mileage or kilometers as we use here only to have the engine dump most of its oil out of the dip stick due to sump compression . I stripped the engine and No 4 piston had a piece out of the lower skirt and broken rings !
I was lucky and no other damage occurred to the engine , the bores were not marked , but I opted to go with a complete set of wossner pistons std size to replace all the pistons instead of just one from BMW ! I was informed these are direct replacements for the originals and will fit on the original con rods . This is not the case as the pin supplied with the new pistons is about 1mm bigger than the hole in the con rod , also the original pistons taper inside to correspond to the taper of the con rod ! The wossner pistons are square faced inside and the con rod won't go far enough in because of the taper on the rod
Has anyone tried to fit these pistons to the original con rods and if so how ? Secondly how many other members have had the same type of failures at such low kilometers 63000 ? Such an amazing car but with this type of poor mechanicals and bad engineering how do they hold such prestige
Well guys any info would be greatly appreciated , oh and before anyone asks if I am aware of the terrible reputation these engines have with timing chains and guides as well as tensioners , yes I have read lots on it but this wasn't the cause of the failure in this case . The chain and the tensioner as well as the guides were all in good order and quiet before the piston failure
Thanks guys for any assistance