I have this bmw325i 2006 bought from dealer. When I bought there was couple bolts missing in the engine gasket valve cover. And had small oil leak from gasket. It had never been big problem. Drove it like that 7 months. Then one day my serpentine belt snapped. I changed the tensioner assembly and belt aswell. After tht it was running fine. Now, I have this engine overheat problem. My oil level is good, even though it leaks it doesn't leak like that. And when engine overheats , the coolant spills out and oil filter leaks oil coz of pressure and heat. And loud noise comes from engine like its about to burst. I took it to mechanic, some said water pump, some said thermostat and radiator, some said vaccum leak, some said head gasket. But my oil looks just fine, oil level is fine, coolant is still green. Idk what the problem is before I go to random mechanic and they fix one thing and later the problem is still there coz that was not really the problem. Feel me? So please help this poor kid.