Thanks mas985. I tried that using an expandable bladder. After pushing water from both ends of the line I was able to force some debris out of the line. Thats one of the major reasons I concluded that there must be something in there catching and holding stuff.

Thanks for doing a little head scratching for me on this. Any other thoughts please let me know.

BTW, you can get expandable bladders that screw on the end of a garden hose in different sizes. Works fairly well on some clogs around the house and is chem free! I got mine at Lowe's but most any hardware store will probably have them.

Thanks again