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 on a tight schedule watched). Two of vehicles start after a few months dormancy and I moved them away. When I get to my '85 MB '85 380SL I find it's dead as a door nail. This car has never failed 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 jump start mode 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) and attemp a start 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?

[BlueSkyJaunte]

Battery might be dead, ya know, no matter how much ya charge it. It happens.

[widebody911]

What cardinal rule did you break?

[nineoneone]

dead cell in battery will not charge.

[RickM]

Originally posted by widebody911
What cardinal rule did you break?

The rule of not hooking up a charger without disconnecting the leads from the terminals. I always thought that was one of the best ways to fry your electronics.

Could be a completely dead battery....will check but lights lit and antenna went up so there's some juice left.

[Jim Bremner]

if that's all that's wrong in life. Your a plessed soul.

[nostatic]

i've had batteries that would power the lights but not turn the starter.

I think that was more of an Oriole rule...

[masraum]

It could be a bad battery, in that case they can have 12.6 volts, but not enough amps to do anything, or it could just be dead, really DEAD. With your 50 amp quick charge and a really dead battery you wouldn't have enough power to start a car. That's why batteries have 350-650 amps, so compared to that your 50 amp charger would come up sorely lacking.

[RickM]

This is making me feel better. As mentioned I'v done this a few time with positive results. However, some of the noises coming from under the dash sounded like they belonged in a '50s B horror flick.

Fingers crossed.

[dhoward]

Originally posted by RickM
The rule of not hooking up a charger without disconnecting the leads from the terminals. I always thought that was one of the best ways to fry your electronics.

Could be a completely dead battery....will check but lights lit and antenna went up so there's some juice left.

Never heard that one.

[rick-l]

Let me do some math here.

Lets say you have a 90 amp-hour battery.

You charged it for 5 minutes (1/12 of an hour) at 50 amps starting with a completely discharged battery. You added 4.2 amp-hours of energy or 5% of its capacity. Did you have a few more minutes?

Sounds like the 50 amps from the charger pulled in the solenoid and did nothing else with very little help form the battery.

Originally posted by RickM
Well, as embarrassed as I am to admit it, I hooked my trusty Sears charger to the - / + terminals on the battery,

If the -/+ on the battery were hooked to the +/- on the charger that is another matter altogether.

[VINMAN]

Shouldnt have any problem hooking it up with the cables on.

[turbo6bar]

It won't charge at 50 amps for the full five minutes, unless the charger is some monster behemonth. You might get 50 amps for 10 seconds before it drops down to 10 amps.

[dhoward]

As I read it, you had the charging cables on backwards for 5 minutes, right?

[turbo6bar]

He hooked the cables to his testicles??? Why did he do that? What difference does it make if they're on backwards?

[RickM]

I don't know where I say I hooked it up backwards...? The leads were connected properly.

[nostatic]

you put lead in your testicles? This is getting more and more strange...

[dhoward]

Originally posted by RickM
I don't know where I say I hooked it up backwards...? The leads were connected properly.

I misunderstood.....

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

The only right and wrong way I know of is correct polarity or wrong polarity.
Charging rate in this situation just depends on how you want to treat the battery.
If you hooked it up set to the "Start" charging rate for 5 minutes and tried to turn it over would be no different then letting it sit at a lower rate for a longer period.

[dhoward]

Originally posted by nostatic
you put lead in your testicles? This is getting more and more strange...

He meant to say lead in his pencil..

[nostatic]

he tried to charge his battery with a pencil? No wonder it wouldn't start...