Engine Died

On Jun 4, 2:31 pm, Dean > wrote:
> I know its wrong, but I always just connect straight from battery to
> battery, red to red, black to black. Can't see why this is a problem,
> personally.

I often do the same, but perhaps I'll think twice in the future after
reading Mike's remark.

The inner workings of electricity often fail to conform with "common
sense". If in doubt, best to research the facts yourself rather than
relying on some dude on the internet who goes around passing off
speculation as fact and "can't see why this is a problem."

Harry

Thanks, gents. As described, the lights come on, but I'm not sure whether
that's with the jumper cables connected or not. Let me see if I can get
the battery somewhere prior to my getting up there this weekend to
determine if it's drained dry but rechargeable.

With each kid I tried to provide the basics of mechanical knowledge so
that they would know how to co-exist with an expensive piece of
mechanicall hardware. The only thing I really taught them was when in
trouble - call Dad.

speedo262 wrote:
> Thanks, gents. As described, the lights come on, but I'm not sure whether
> that's with the jumper cables connected or not. Let me see if I can get
> the battery somewhere prior to my getting up there this weekend to
> determine if it's drained dry but rechargeable.
>
> With each kid I tried to provide the basics of mechanical knowledge so
> that they would know how to co-exist with an expensive piece of
> mechanicall hardware. The only thing I really taught them was when in
> trouble - call Dad.
>

One thing to remember is there are two ends on battery cables....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Mike Romain wrote:
> When a battery discharges and charges, it gives off hydrogen gas. Get a
> spark on the cable when you connect it and the top can blow off the
> battery, either one.

I'm reasonably sure they only generate H2 when they're being charged.
Actually, I believe it's when they're being charged beyond full charge
(or at a point very close to full charge).

> Been there, had it happen with a full charged battery that just came off
> a highway run. Pieces of battery went through the hood and I got
> covered in acid with cuts to my eyebrow from a chunk. I was lucky, snow
> was right there to dive my face into and water was 10 feet away.

It's possible you had a bad battery. I had one start fuming once from
an internal short; fortunately, it didn't explode or spew.

> I also have seen dead batteries act like a sink needing several minutes
> charge via the boosters.

I find it much preferable to let the dead battery charge from the good
system for a few minutes before attempting to start the dead car. I like
the idea that, unless the dead battery is very very dead (i.e. defective),
this is taking most of the load off the good system. I also don't like
the idea that the slightest movement of the cables during a high-current
starting attempt could make sparks near the newly-charging dead battery.

clifto wrote:
> Mike Romain wrote:
>> When a battery discharges and charges, it gives off hydrogen gas. Get
>> a spark on the cable when you connect it and the top can blow off the
>> battery, either one.
>
> I'm reasonably sure they only generate H2 when they're being charged.
> Actually, I believe it's when they're being charged beyond full charge
> (or at a point very close to full charge).

As soon as they start bubbling, they are venting H2. This is very early
in a charge on a dead battery.

A dead one from say a left on light also will start to charge back up as
soon as the power is shut off.

Then the car might be dead from a bad connection, so the battery could
be charged recently even so the boost can spark there too.

>
>> Been there, had it happen with a full charged battery that just came
>> off a highway run. Pieces of battery went through the hood and I got
>> covered in acid with cuts to my eyebrow from a chunk. I was lucky,
>> snow was right there to dive my face into and water was 10 feet away.
>
> It's possible you had a bad battery. I had one start fuming once from
> an internal short; fortunately, it didn't explode or spew.

Battery was fine, just fully and freshly charged from a high speed 4
hour run when the spark happened at that end of the cable, forget the
dead battery end...

>
>> I also have seen dead batteries act like a sink needing several
>> minutes charge via the boosters.
>
> I find it much preferable to let the dead battery charge from the good
> system for a few minutes before attempting to start the dead car. I like
> the idea that, unless the dead battery is very very dead (i.e. defective),
> this is taking most of the load off the good system. I also don't like
> the idea that the slightest movement of the cables during a high-current
> starting attempt could make sparks near the newly-charging dead battery.

Yup, so I keep one connection over on the engine block to lower the odds.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Dean wrote:

> I know its wrong, but I always just connect straight from battery to
> battery, red to red, black to black. Can't see why this is a problem,
> personally.
>

Because the spark that occurs when you make the final connection is
RIGHT next to the hydrogen gas coming out of the battery....

clifto wrote:

> Mike Romain wrote:
>
>> When a battery discharges and charges, it gives off hydrogen gas. Get
>> a spark on the cable when you connect it and the top can blow off the
>> battery, either one.
>
>
> I'm reasonably sure they only generate H2 when they're being charged.
> Actually, I believe it's when they're being charged beyond full charge
> (or at a point very close to full charge).

Nope, just any time they're being charged. And most batteries *always*
have a bit of hydrogen in them at any given time, even if they've been
sitting for a while.

>
> I find it much preferable to let the dead battery charge from the good
> system for a few minutes before attempting to start the dead car.

Yes, this is the best method to use, both for the battery and for the
car providing the jump.

Just be careful DISconnecting the cables, as a spark then can cause a
battery explosion just as easily as when first connecting the cables,
that is why the last connection made and the first connection
disconnected should be at the engine block of one of the cars, far away
from the battery itself.