G'day Steve,
Can I connect the red wire with the diode to the battery side of the solenoid so it can charge the battery when it's running and leave the black wire from the Alternator not connect to anything as I don't need to lights at all.?
If you have the stator that doesn't use the Voltage regulator then yes just connect the red wire to battery side of the solenoid and don't
use the black wire.
I have heard with diode only system it's 3 amps . The resulting pulsating DC can charge the battery, but because there is no regulation, the voltage can fluctuate with engine RPM. This means that while the battery is likely to receive charge when the engine is running, the voltage may vary and could go above what is safe for the battery if the engine runs at high RPM for long periods.
Stator with Diode and Rectifier/Regulator 5 amps: Other models may come equipped with a more complex setup that includes a rectifier and a regulator. In this configuration, the stator generates AC power that is rectified to DC and regulated to maintain a consistent voltage output suitable for charging the battery and powering electrical components without damaging them.
With a Mud Mower I would think you would be using high RPM for long periods .
I'd keep an eye of the battery as the overcharging may cause the battery to overheat, bulge, or even leak.
Cheers
Max.