thanks for the reply's
yes I have adjusted a great deal to upper and lower blade holders
after exhausting examining, I have determined that the lower arm moves slightly to the right as it tops the stroke and same on the very bottom of the stroke
i have checked the arm and bushing alignment and I am pretty sure it's either the shaft of the motor is slightly bent ( not too likely) or the elliptical may be either machined incorrectly bent
of course, since I have taken it part way apart porter cable will do nothing. LOL, that's what I get for being a fixer and not taking it back.