2000 Other BMW Models WHAT CAUSES THE BIG END TO BREAK

2000 BMW
70,000 MILES • 4 CYL • FWD • MANUAL
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MCTANZANITE
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WHAT CAUSES THE BIG END TO BREAK
Jun 18, 2009 at 4:02 AM
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MHPAUTOS
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HI there,

what i need to know is what has actually failed, but in a nut shell it will normally be an oil supply problem, if the oil supply to any bearing is compromised it will cause it to over heat and fail very quickly, It will be characterized by bearing knock, a rhythmic deep knock as the load is applied to the failing bearing, as the bearing fails the running clearance between journal & bearing increases to the point the the hammer it self into oblivion, but what you must determine is why the journal was starved for oil if all others were ok, often the small oil galleries are blocked by carbon deposits laid down over many years via lack of servicing, dirty oil is often the root cause of a singular bearing failure, other factors can and do cause problems, but oil and the general condition of the engine is where you should be looking for this failure.

Mark (mhpautos)
Jun 18, 2009 at 5:24 AM
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