I put the engine back together and now it runs perfect. I guess it was my fault for not tightening those screws down before running the engine. I just hope that everyone would learn from my experience.

I always use after run oil. I run Trinity Platinum 20%, good fuel that Ive never had a problem with. I have no clue why some rust is showing up on the back of the crank. Its probaly from the air coming through the backplate when it wasnt tightened all the way cause I always store the piston at TDC. I think after another half gallon running at high temps the rust should disappear.