When my Honda harmony tiller would not start I gave it to a back yard car mechanic to look at. He said that he took the valve cover off and found the pushrod disengaged from rocker arm and the intake valve was stuck open and he could not move it even when tapped. This guy could fix it if it is worth going further. Do you think it is? do you know what happened ? and do you have a parts site? I do not have many hours on this 04 model.