Hello everyone, here is my problem: I made a very simple mechanism by layout assembly, created the blocks, mate them and built the parts from them.

Essentially is a slide crank guided by a 4 bar linkage. I fixed poin A and B and linked B and C with horizontal mate. Line red made also horizontal.

Started animation, applied a motor to the first bar to the left, everything seemed fine but when i started motion analisys point C and red line were no more horizontal and kinematics resulted in a mess. Mates appread active but not "working". I tried to verify the layout but everything seemed ok. Close Solidworks and restarted, recalculated motion, now it's in animation that point D and E are broken while motion study is ok.

I'm not  an expert in motion but this is an akward situazion happend in a very simple mechanism so it stressed me up and dissapointed me!

Can anyone explained what happened here or what mistaked I did?

Thank you very much