I took the motor to a local garage/small engine shop this a.m. It was fixed later in the day. Friend that works there said it was one of the small jets inside the carb that was plugged. He said that 1 wire from a wire brush was all that would fit thru the orifice & clean it out. He put it back together & set the idle. He referred to that enrichment screw w/block as an "EPA screw". He said most all small motors are that way now. Mfg did that to appease EPA folks.

It runs great again...just like new. No more smoke or surging.

Thanks for all ideas.