Okiki Olufokunbi Posted June 7, 2017 Share Posted June 7, 2017 Hello folks, I do need some assistance and help in trying to understand why an E7 PLN engine failed hours after the rebuild. The truck operates out of Africa. I have attached some pics and will attach more as I get them. The engine had to be rebuilt after it threw a rod, poked a hole in the sleeve and broke the cylinder block. This happened because the connecting rod bolt came loose and the rod came off the crankshaft journal. So the rebuilt involved a new block, and a new crankshaft amongst other things. The truck had an inframe sleeve replacement a year prior, and the pistonless PAI kit was used during the replacement. The PAI Main and rod bearings that came with that sleeve replacement job were not used back then, but was used with this rebuilt. Apparently these PAI rod bearing were coated bearings After this rebuild, with the installed PAI main and rob bearings, the engine was started up and then left running at idea about 3 hrs. It was then shutdown for about 8 hrs, and restarted again. 2 hours into the second run (at idle), the engine shut itself down and would not restart. After letting the engine cool down, the engine was started up again, but it began to give a knocking sound. It was quickly shutdown, and the oil was drained and the oil pan drop. The aftermath was ugly my friends. The number 2 cylinder rod bearing had overheated, spun around and extruded. The rod bearing oil hole was virtually plugged off with metal shavings and coating material. The other 5 rod bearing were all scarred up, and already have shavings. Their oil holes were still open, but had already started being plugged with shaving materials. But they did not look like they had spun. The new crankshaft was again shot. It was quite obvious that to me and all so far that the journals seemed to have lost lubrication, but number 2 likely went all the way dry and stopped receiving oil completely. I am trying to understand why, so as to really get to the root cause of the failure. How does oil get to the individual rod bearings? Unfortunately I don't have my E7 manual with me, but I was under the impression that each of the main bearing got supplied oil from dedicated Engine block oil gallery , and then the main bearing would supply the rod bearings through the oil paths in the crankshaft. Is this incorrect? One of the Tech was contending that the oil flowed down from one journal end of the crankshaft to the other but is he correct? This was the first time the Techs have ever used coated bearings in any of their rebuilds, to their argument is that the coated PAI connecting rod bearings were not good, and definitely wrong for the application. The Tech are of course skeptical, and contend that the rod bearing started shaving off as soon as the engine was started, and finally the number two shaved off to the point of plugging off the oil hole, stopping oil flow, then overheated. Has anyone here experienced a failure as a result of using coated rob bearings or PAI rod bearings in particular? Please let me know if you have any more questions or need more information to diagnose. I have my opinions at to what happened, but wanted to get your inputs first. Thank you for you time OO 1 Quote Link to comment Share on other sites More sharing options...
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