2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 255Get this manual
Electrical system NOTE: To prevent the engine from starting when cranking it, be sure to disconnect both spark plug caps Do not remove the clip from the engine stop lanyard switch If measuring the output peak voltage under the unloaded conditions, disconnect the connectors When using the manual starter to crank the engine, the voltage values may vary depending on the speed at which the starter handle is pulledPulser coil output peak voltage: Whitered (WR) Black (B) rmin DC Unloaded Cranking 5.1 2.6 Loaded 1,500 5.3 3,500 8.4
3Measure the ignition coil resistanceReplace if out of specificationS6AG8050
Ignition coil resistance: Primary coil: Orange (O) Black (B) 0.260.35 at 20 (68 F) Secondary coil: Spark plug wire Spark plug wire 6.810.2 at 20 (68 F) 4Install the spark plug caps to the spark plug wires by turning the caps clockwise, and then connect the ignition coil connectors