On Thu, 26 Nov 2015 14:18:19 -0500, Micky
wrote:

Battery charger only puts out 11.5 volts with no load on 10 amp
setting, less when on 2amp setting. Puts out 7+ on 6 volt setting.
With no load.

It used to put out plenty. I've only used it a little bit since then.
If windings in secondary were shorted, output voltage would go down,
but what would make the secondary short?

Left outside, plugged in and charging a crummy battery, for about a
week, but covered from the rain and it didn't rain anyhow.

I just measured the voltage on one of my battery chargers. Using my
analog meter, it shows slightly less that 12V with no load. It charges
batteries just fine!