Very nice rebuild - I just noticed the thread today and have to say that your work is top notch. I wish I had some suggestions on the foaming oil - but i'm clueless. Could the oil have become contaminated or mixed with another fluid? not sure what that would do - but if water or something was accidentally introduced I supposed it could do this.. then again I have no clue. Good luck - with all you have overcame on this tractor, I figure this will have a much simpler solution.