Engine rebuild

What is your question?

Hello. I am rebuilding my brothers, 2002 Toyota Corolla LE, engine. Everything has been done to spec and taken to a shop for measuring, honing, cleaning, etc... After putting the pistons and connecting rods back into each cylinder, tightening them to spec, I rotated the crankshaft with the flywheel. There was no issue until I rotated the engine 90° ,horizontally, to start the timing; it would get snagged everytime the pistons were aligned, dead center. It's getting snagged and I'm not sure what could be causing it? It was fine before, but now it's not? Any ideas are much appreciated. I'm about to remove the bottom casing to check the thrust washers but I wanted to know if this is common

What makes this problem better or worse?

Lube and rotating back and forth

How long has your 2002 Toyota Corolla had this problem?

3 days