ArraynI took my time to (correctly I hope) initialise the case. Please take a look at that. These values were extracted from a Rigid Dynamics analysis, but that's the best we can do. The main coordinate system is placed in the same place and orientation in both RD and ED analyses.nWe start the simulation while the piston head is in the Top Dead Centre. The crankshaft rotatates counterclockwise, as can be seen on the last screenshot.nnThe real question is: why it worked previously but now it doesn't? In both cases, the bonded contact glued the two interfaces together, the only difference was that previously the glue was not distribued along the whole circumference (theta direction) of the thread.nnI'd be grateful if you could take a look at my project and see what could've gone wrong. Please find it attached below.nArrayn