There is a diagram of the chain drives of an ATCO 14-20 4 stroke in the parts and manuals section of this site, but you have to subscribe to get access to it. The manual is a protected PDF so I can't just post the diagram here. However I believe photos of ATCO chain drives have been posted here before - if you do a search you should find what you need. You will probably find it better just to subscribe to the mower manuals section, and download the whole manual. That way you will have access to download any of the mower manuals for a year.
