Broke a cardinal rule....how bad do you think?

[RickM]

Well, I've done it before and never got bit by the good sense warnings you always hear.

I needed to fetch a few vehicles from storage and was pressed for time (while someone watched). Two of vehicles start after a few months dormancy and I move them away. When I get to my '85 380 I find it's dead as a door nail. This car has never faiiled to start but under the circumstances it's understandable.

Well, as embarrased as I am to admit it, I hooked my trusty Sears charger to the - / + treminals on the battery, switched to 50amps and let it sit for 5 minutes. When I went to attempt a start (without disconnecting the charger) I hear nothing but a bunch of clicks and a loud humming from under the dash.

Uh boy. There was no smoke, sparks or anything of that nature but when I tried to charge the right way (only about 10 minutes) I don't even get a solenoid click.

I'll need to get the car to my house and pull/charge the battery overnight and try starting again but I have a bad feeling I'm screwed.

Any idea what I might have fried or what I should look for before attempting again?

If the battery has sulfated plates from sitting dead for a long time, it will not want to take a charge/may not take a charge at all. The best way to bring it back to life is with a very low amp trickle charge, it once took four days to charge the MB-88 battery in my old 300D with a battery tender. I you need to move the car, I would simply install a good MB-88 Interstate or equiv., though be aware that the radio may need to be reset if it loses voltage. You probably didn't do any damage, it's just that you need way more than 50 amp to start that v8. Though, battery chargers do put out "dirty" dc voltage and some cars(Jaguar) are ver sensitive to "dirty" voltage.

[Strife]

Cheap battery chargers don't even put out real DC, they put out half-wave rectified AC (pulses). If the battery is really dead,dead,dead, I would think twice about charging a battery with a cheap charger while attached to a car . Cheapo's also put out way too much voltage, hoping for the battery to bring it down to reasonable levels. Batteries with dead cells won't do this.

[Eltee]

I was looking at a wiring diagram - the only thing between the starter and battery on your car is the ignition switch. I wouldn't doubt it if the battery was damaged. Might want to try a new battery. Interested to hear what you find.