Re: 1975 135 horse evinrude
If you have two yellow wires coming off the stator, one with a white stripe, they lead to a voltage regulator. You can check the regulator with an ohm meter to see if the diodes inside are good. That part is what converts the AC current to DC for battery charging.
In general you can test stator and trigger coils with an ohm meter to see if they are in spec resistance wise. Also with a special adapter (DVA) you can check charge coil, trigger and stator peak volts output to see that they work properly as well.