Mercury Outboard Wiring diagrams -- Mastertech Marin MERCURY WIRING DIAGRAMS. The linked images are printable but may print across more than 1 page (in order to be legible). Most models also have black-&-white-only PDF files Internal & External Wiring Diagram Merc 500 CD ignition 1976-78 Electric Start... Merc 500 CD Normal Older Mercury Outboard Wiring - YouTube Click to view on Bing1:50 we go again- another older Mercury motor with electrical issues. This one is slightly different because it has been in use and running flawlessly. THEN- it quit and they had to be towed inAuthor: ShipShape MarineViews: 117K Mercury Outboard Wiring Diagram | Free Wiring Diagram Collection of mercury outboard wiring diagram. A wiring diagram is a streamlined traditional photographic depiction of an electric circuit. It reveals the parts of the circuit as simplified shapes, as well as the power and also signal connections between the devices.