2010 forester replaced engine myself with used one. Now knocking noise when put in gear.

What is your question?

At first engine was difficult to mate to gearbox(auto) but finally went together. After install complete, started right up and drove perfectly for few days with limited miles until noise began. When iremoved old engine, torque converter was still bolted to flexplate. Install was also done with torque converter attached to engine.

What makes this problem better or worse?

Putting into gear makes worse

How long has your 2010 Subaru Forester had this problem?

Started yesterday