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Arne Lindholm
12-23-1998, 08:15 AM
I am curious to find out if there is somebody else out there with this experience:<br>After typical german Autobahn 185 000 km steady drive, my M5 525 TDS Touring -94 (6 cyl. diesel /w turbo) engine suddenly failed. A tiny clunking sound started<br> when crusing 120 km/h and while stopping the clunking (once per rev)carried on and grew to a final coarse clunck and the engine stopped. Finding: One of the two bolts in the second piston rod bearing cap had unscrewed and fallen down in the oil pan. Bolt is complete and was bent about 90 degrees when it finally stopped the engine. Other bolts are all tight. Oil level good, always runs synthetic. No other bearing wear present. Ever heard of that kind of failure? Merry Christmas /Arne

Hans TILLIE
12-23-1998, 11:00 AM
<i>: Finding: One of the two bolts in the second piston rod bearing cap had unscrewed and fallen down in the oil pan. Bolt is complete and was bent about 90 degrees when it finally stopped the engine. Other bolts are all tight. Oil level good, always runs synthetic. No other bearing wear present. Ever heard of that kind of failure? Merry Christmas /Arne <p></i>Arne, mmmm, not a nice present for X-mas (I know, my wife just crashed her 316i, but with luckily no severe injuries for her, I felt very cold when a guy from the police called me to say she was in a rather serious car-accident, anyway...)<br>I once had this problem with a diesel-engine. The cause was a bad injection causing misfiring in the second cylinder. It fired when the piston was coming up, thus creating massive force on the piston which didn't last of course. They had to change the negine because the bolts knocked themselves anywhere on the inside of the engine leaving damage and scratches, and they had to change the entire injection system because that was responsable for the misfiring and misinjecting fuel. the symptoms in my case were (a few weeks before failure) smoking when cold, difficult to start when cold and that sort of stuff. They couldn't figure it out untill.. you know the rest of the story.<p>Good luck.<br>Hans.<p>'91 520iA<br>ex-'93 316i (RIP)


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