I have an 80's model gas powered 4cyl (commercial ford engine) "Dynamow" lawn mower. It's a great mower but the motor surges. I can't get the govenor to stabilize. Does anyone have any experience with this type mower or suggestions on how to correct the problem? I would love to find a manual for this mower.Does anyone know of a website to procure old lawn mower manuals? Thanks in advance for you prompt respones.