On 5/2/15 3:57 PM, micky wrote:
To everyone, yes the battery was very much discharged. I knew that.
The hydrometer shoed 4 cells in the red (semi-cheap hydrometer, no
number assigned to red) and the other 2 very close to the red.
However the battery's voltage was above 12.6 anyhow. (well maybe I
didn't wait until the "surface charge" dissipated, like Philo said to
do. But then the owner came and took the battery away. He has a
charger he thought wasn't working. This is for the truck he rarely
drivesl, but I guess he wanted to drive it the day he got the battery.)

I quit fooling with hydrometers decades ago. In some batteries, it's
hard to get to the electrolyte. Gas bubbles, as in a glass of ginger
ale, will cause false readings.

Before charging, voltage should tell you the state of charge and if all
cells are working. Headlights will show how the battery handles a load
of a few amps. It's also a way to check the state of charge if a
battery has recently been on a charger. Turn the lights on 15 seconds,
then off.

In my experience, a deeply discharged battery charges slowly at first
because the electrolyte is weak.

Most DMMs will measure 10A DC. That's a way to check the gauge on the
charger.