This BMW came to us very loud knocking. Obvious crankshaft big end bearing failure. Possible one or more main bearings spunDuring engine disassembly I found only one big end spun. Cylinder block is good. Only honing will be required. After removing cylinder head I immediately noticed that some pistons are not looking normal. They are damaged by faulty over fuelling injectors. All injectors will be replaced.
Thankfully no damage to cylinder block. Bores will be refreshed on honing machine.
Sourced N57 Standard original crankshaft. New main bearingsReplaced damaged pistons and conrods. New bearingsCylinder head completely disassembled and cleaned. All valves re-seat and steam seals are replaced. Original Elring cylinder head gasketNew N57 timing chain kit installed Rebuild engine
