Tried using Simple Green. It removed some debris but not all. Then on to vinegar. Nope, no results. Next was 2 psi of air pressure. Nope. Figured it was a lost cause. It got the drill. Back together and it's running. Started quite easily, maybe 6 pulls after pushing the primer button. Thanks to all for the help on this. My friend's eyes lit up when he saw it running. On to the next project...I think I've got a mid 60s vintage O&R around here somewhere...