At 09:22 PM 12/2/2010, brett rueff wrote:
>Battery at Rest - 12.57V (after an overnight charge to make sure its full)

If you mean right after you took the charger off, that's a bit
low.  Usually it would be over 13 v for at least a little while.  If
it's sat for some hours after charging it's still a touch low.  The
new off-the-shelf Group 48 battery I've been carrying around unused
for a few weeks shows 12.65 v.

>Cranking measured across battery (+ battery post and - battery post) - 10V

I just now measured 12.25 idle -- my charging voltage is 13.9 at the
battery, so I'm not surprised that it isn't fully charged.
Drifted down to 11.8 with ignition and lights on.
Cranking about 10.9.
I'm not crawling around the starter for you tonight... ;-)

>Cranking measured at starter (+ on main solenoid pole - on starter
>housing) - 8.5-9V

Wups, you're losing a volt and a half in the wiring somewhere.  Not good.

>Voltage Drop positive side (+ to pos battery terminal - to solenoid
>main pole) - 0.2V

ok.

>Voltage Drop negative side (+ to starter housing - to neg battery
>terminal) - 1V

Right.  That's not acceptable.

>So I concluded starter. 8.5-9V should be good enough for a cranking
>right?  I removed and took it to FLAPS where they bench tested it
>and said it was fine - I watched the test and it span like mad.

It certainly ought to have spun like mad with no load on it (or does
the test load it?).  CCA ratings assume a minimum of 7.2 volts (i.e.
the new battery can deliver XXX amps for 30 seconds at 0F without
falling below 1.2 volts per cell) but I have my doubts whether that's
enough to crank with.  Only doubts though, not knowledge.
>cranking.  Based on my testing that is all I can figure is the
>problem.  Suggestions before I pull the thing apart again?

Fix your ground problem and see what happens.  Have battery tested
ditto -- I think it's weak unless this thing is really cranking hard.

Yrs,
d