Where is my small engine wiring diagram? | Briggs & Stratton Briggs & Stratton sells electrical components only for engines. If you are replacing or rebuilding parts of the small engine on your lawn mower, snow blower or other outdoor power equipment, the basic schematics or wiring diagrams of our alternator systems are available in our guides below: Small Engines - » Basic Tractor wiring diagram This is your basic tractor wiring diagram. There are entirely too many different setups to even begin drawing or posting all of them on this website. The above diagram will give you an at a glance idea of how a tractor is wired up. The more bells and whistles on a tractor, the more wires and switches and relays.