I just rebuilt a broke crank built engine that had two nozzles laying in the lower pan. They were un related to the broken crank. It seems like mahle Motorsports pistons' skirt extend further out of the bore, possibly causing the issue if the assembler isn't paying attention.
On any Duramax, stock or 'built', you need to rotate the engine over and aim each nozzle correctly at it's piston. A lot of them even need bent a tad to prevent the piston from hitting the nozzle,not just rotated to center in the hole. Cast pis tons have the little hole that the nozzle aims into but forged do not.
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