Mark Van Lienden, CGCS said: Have you checked linkages ? The valve bank has mounting bolts that can be loose and cause that or tight but set wrong.You also say new motor did you bleed all the air out? I think they say with engine running hold steering all the way left. If it is cable steering there was a way to bleed out the air but I forget what that is.
A good reminder, I remember back at Lake City Community College in the mid 80's, our one instructor Ed Combest would say, "90% of your hydraulic problems, are mechanical" Percentages with the new equipment might be a little different, but I would bet for the most part still holds true.
Mel