Whilst Dad was visiting, we put his portable oscilloscope across the two terminals on the back of the tachometer, and found a very nice mV signal that changes frequency with engine revolutions. This means that a bit of circuitry plus
Finding the right cable size for the water pump
Given the voltage drop at the pump, yesterday evening’s project was to wire the pump with 8 AWG (10mm sq) for the positive feed, and a bit of 2 AWG (35mm sq) for the negative feed. Unsurprisingly, the pump worked