jtaylor wrote:
Got a diesel, and it gets cold here. There's a block heater, but I also
have a 1A charger that could be attached to the same extension cord - would
there be any drawback/problems with leaving this connected (on the battery
side) _all_ the time? It's a cheapo transformer & diode unit.

When I worked for a company that had many standby generators I remember
that they used a 50 ma trickle charger for each battery. I'd try
connecting a diode or resistor in series to bring the charge rate down
to that amount.
Engineman