That's interesting SBP and maybe ties in with my thoughts earlier in this thread of a shorted battery cell.
Given a working alternator regulator, the only factor that could drag down alternator voltage that much would be excessive load from equipment or battery itself. If you intially saw the normal regulated 14.3 -14.4 volts then equipment can be excluded so battery is failing in some intermittent way to cause it to draw excess current, despite being fully charged referenced to its current state. Since this excess current can only be dissipated as heat, l would expect it to get hot quite quickly. Has anyone noticed this prior to the full failure?
I guess the open cockpit of an M3W dissipates attendant smells which would be another tell-tale sign of imminent failure.
