I personally invented killing my starting battery by leaving something on. ;)  If I leave a door open in my EV the interior lights will kill the battery overnight with no problem.  I discovered quickly that most jump start boxes will not even think about turning over the EV's V6 on a cold winter day.  I have since purchased one of these no-frills units http://www.youtube.com/watch?v=RZeRs3rMxEo which is just a battery in a box. No AC converters, USB ports, air pumps, etc.  It has performed as advertised on a dead battery. I'm sure it would work in a Vanagon too.

The bigger Black and Decker units are pretty good too.

Bryan

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Loren Busch
Sent: Wednesday, June 02, 2010 11:50 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: I could use a little help

On Wed, Jun 2, 2010 at 7:18 AM, Dave Mcneely <mcneely4@cox.net> wrote:

> ---- John Rodgers <inua@CHARTER.NET> wrote:
> > What capacity in Amps do  you think would be appropriate for jump
> > starting either the Vanagon or another vehicle?
>
> More than one of those cheap portable hot shot devices makes available.
>

If you have a really dead starting battery the portable battery packs
probably aren't going to work. Most of them are a 17ah battery inside.  They
will work with a battery that is just down to the point where it won't turn
over the engine.  But big or high compression engines are going to be hard
to start with the jumper packs.  And the connections become critical.  If
the clamps on the jumper cables are corroded and you can't get a good
connection no joy.  Apparently the jumper packs the tow truck drivers carry
are beefier because I've seen them start engines with flat dead batteries.
The advantage of hard wired high amperage connectors (like the big Powerpole
connectors mentioned earlier) is that you get a good connection on that
end.  IIRC a starter is going to try to draw 75-85 amps so wimpy jumper
cables are going to heat up fast and also use a lot of amps just pushing
through wires that are to small.