To update those interested...
Well, the engine is back on the board. We completed the rebuild this morning. It was actually working just fine about a week after initial failure, but we had found further damage that was missed originally, that we did not wnat to leave to chance. The biggest challenge was getting tech and parts during the holiday season.
In the end, it would appear we were very fortunate in this failure. No damage to the block or crank were noted. The affected hole, #7, the pictures indicate pretty accurately was destroyed, but the block spared. Number 8 hole had shrapnel damage, and the whole power unit was replaced. Despite, oil pan stiffening / baffle #5 piston also had a small chunk missin from its skirt, resulting in some damage to the liner as well - so it was replace. Thats what we finished up yesterday.
One of the turbos was toasted, new installed. After initialled start up, we noticed oil leaking from turbo flangeg. After troubleshooting we pull cylinder head on 1-3, and found exhaust valve on #1 loose, its guide being wore out. So we replaced that head. She must have leaked quite a bit of oil, cause after that, we still had considerable oil leaking from turbo flanges, which threw us for a loop. So we replaced again the turbo, but in the end, must have been residual in the manifold, as it sort itself out under load - and never came back.
I had never workd on these engines before (onboard we have V8 500 hp Cat D397, V12 750 hp Cat D398, and the 1000 hp V16 Cat D399) very simple machine full of iron. However I would like to get the designer over to have a few words with him on the exhaust bolting. That guys needs to bone up on the impacts of his design vis a vis serviceability.
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