[patrickt]

Remember, your ammeter is measuring current. If your battery is fully charged, and you fire her up, it's perfectly normal to see 25 amps going through the meter for a couple of minutes as the battery recharges to full capacity. If you are still seeing greater than a few amps going through the meter after the car has been running a while, and your system voltage is a normal value of under 14ish volts, then you have to ask "where is the load on that side of the gauge?" Is there a high amp load (like a fancy audio system), or maybe an ignition system, maybe the fans, that are wired directly to the positive terminal of the battery? Or to a lug that is between the ammeter and the battery? Or maybe it's a poor connection that is creating heat -- just like a space heater. Or maybe it's the battery itself. Remember, you only have amps measuring on your gauge when you have current, and you only have current when you have a load of some sort. 99.9% of the time, there is less than a couple of amps running through your ammeter, and that's just to keep the battery trickle charging after it has been fully charged up.