(Dan Thomas) wrote in message om...
"Ali Ghorashi" wrote in message ...
The alternator's field current is controlled by the regulator,
and when it's on but not turning the field gets pretty much full
battery voltage. That voltage would be a bit higher than normal if the
other alternator is running, but not dangerously so. The field can
take it.
The danger, as I see it, is either that the field of the
alternator on the dead engine can get hot after a while if it's not
spinning and could burn out (the fan isn't cooling it) or that the
pilot may forget to make sure the alterators are off before starting
the engines next time. Two fields can suck up enough current to make
starting an engine that much harder.

In my Mooney we found that the engine starts a little faster with the
alternator off, so that's how we start it.
-Robert