bdphil,
When I first read your post my first thought was, the engine is too rich. Out of the box, I thought my ZDZ 80 was having a seizure the first time it ran. The low needle is supposed to be set at 1.5 turns from stop it was 4 turns out. I reset the needle to factory specs and the engine ran great. As long as everything is tight on your install it should work fine. Readjust the engine and try running it somemore. Let us know what happens.