[Shop-talk] [Roadsters] Slightly OT--car won't start

[TR3driver at ca.rr.com (Randall)]

>  Then have some one
> try and start the car.  If the voltage goes below about 11 V then the 
> battery is dead.

I agree entirely, except with that point.  If you check while the starter is
actually cranking the engine, as low as 9v is still considered normal in
reasonably warm weather, and it can drop below 7v if it is very cold.  "Cold
Crank Amps" (aka CCA) is measured at 0F and 7.2 volts.  Even RC (Reserve
Capacity, not a measure of starting power) is measured at 10.5 volts.

Also, a shorted starter can pull the voltage down low, even with a healthy
battery.  Certainly a bad battery is the more common cause, but I have had a
bad starter do the same thing.  (Although the smoking cables were a hint
<g>)

-- Randall