In a message dated 15/03/2004 12:04:49 AM Eastern Standard Time,
LISTSERV@GERRY.VANAGON.COM writes:

The full  detail, along with a couple of pictures to explain, is on the  web
here:  http://users.rcn.com/jhecht/batteries.  The basic  situation is that I
bought an Optima yellow-top, and on the instructions of  someone in an RV
shop we bought an isolator (the type with two diodes  inside to direct
current) that is used by RV folks to connect their second  battery.  Steve
first wired the old battery to the isolator, and with  just that connected
the van wouldn't start.  He checked it and played  with it but couldn't
figure out why it wouldn't work.  It was dark out  by then, so we couldn't
experiment further, but he also felt he needed more  knowledge than we had.

If you think you might have any suggestions,  please take a look at the
website, which includes the wiring chart we're  following, photo of the old
battery explaining what we connected (bad  quality, unfortunately, it was
dark when I took it), and a list of  hypotheses as to what might be wrong.
And if you reply, PLEASE copy Steve  on your email
I did not copy Steve as I don't find his email  address in your message

(all  those ormswyn
addresses - I don't know which he actually checks) so he'll  be able to mull
over your thoughts.  He's not on the vanagon  list.

Joy, I just went through this process on my Westy  and helped out a few
others with info.  See the archives for lots more  details.  First thing I will say
to you is to use the Sure Power model  1315 to bridge your two batteries.  Of
all the methods I have personally  tried this one is the most successful in
all respects albeit more expensive but  in the long run it is the best way
period.  I am going to copy below a  few messages I sent to others who involved in
the same task as  you and hopefully all this info gets into the archiove for
future benift of  all.  Good luck and hope to see you soon at Everybus.
Start of copied messages ............
<<<<<No, I  did not miss you post.  I've been mulling over all the advice on
this  issue now for a few days and decided that the Sure-Power gadget was the
right  way to go.  Called up to the local RV place and they had two in stock
at  $124.  Went up and got one and spent most of Monday installing it.  I  see
a big difference in the voltage of the aux battery after shutting down the
van after short runs now.  Battery is always up to above 13 volts at shut  down.
 I chose to use the aux battery start option so ran a #4 wire from  the main
battery to the aux battery under the van.  Ran a # 14 wire up to  the start
switch for the start position trigger.  The two batteries need to  have a large
wire connecting them, this idea of a 14 gauge wire to limit the  dumping of
the main battery into the aux battery at start up is not right.   It limits the
charge to the aux battery on short hauls.  Granted if you  drive for a few
hours it will work but when using the van for short runs day in  and day out day
after day ith no long runs you will eventually kill  the aux battery if you
have any load normally on it.  Found a sopping wet  floor under the carpet while
trying to run that wire and then the throttle pedal  link popped off and had
to dive under to remove the plastic cover to reinstall,  found the four screws
rusted to the point they needed drilled out.  Ended  up cleaning up that
mess, dumping Krown oil all over the area and replacing the  screws with nice big
stainless ones.  Still trying to get the floor matting  and carpet dry and
still use the van.  PITA this winter  weather.>>>>>>>
<<<<<<<I chose the 1315  because it has the aux battery start option.  Just
need to run a wire from  the Sure Power to the ignition switch wire that
activates the starter.  Big  red and black wire coming from the ignition switch
wiring connector if I  remember correctly.  Better check Bentley or do a test with
a  probe.>>>>>>
<<<<<<David, I mounted the Sure Power  unit on the floor of the aux battery
box, as far to the RH side and in that  small nook as possible.  This gives
plenty of room for the Optima to  fit.  I ran a number 4 gauge cable as recommend
on the Sure Power install  sheet from the main battery to the Sure Power
under the van.  Out the  bottom of the main battery box along side the main wire
and through the same  grommet and then drilled and new hole in the floor of the
aux battery box floor  and used an appropriate sized grommet.  Use caulking
to seal up the space  between the wires and the grommets if there are any.
Used 4 gauge wire  from the Sure Power to the aux battery and from the aux
battery ground post to  ground at the battery hold down bolt location.  I did
install the start  option so ran a 14 gauge wire up to the start switch as described
in the  instructions. Depending on what kind of terminals you use on the aux
battery they and all the wires leading too them my come very close to the
seat  swivel late when turning it round.  Use a piece of heavy carborad as an
interface to check.  If it is too close you can remove the lip of the  swivil
plate in the area where it is too close.  I did this and that solved  the
problem of turning the seat and having it short out on the battery positive
post.>>>>>>>
<<<<<<The stock relay is not  needed if you want to connect your fridge to
the aux battery directly.   Just remove the relay.  The wires coming to the
relay from the front of the  van; 12v power from the main battery, large red wire,
this wire should now be  used to send power to the front of the van to power
the cabin lights, radio and  any other circuits you want to run from the aux
battery,  You will need to  trace this wire to its location on the back of the
fuse relay block, disconnect  it and then find the wires for the accessories
you want to power by the aux  battery then make a 10 or 15 amp (depending on
the circuits you  choose) fused connection between them and the big red wire.
The other  end of this wire at the aux battery box will now connect directly to
the  positive terminal of the aux battery.
The other two wire coming from the front to the  relay are the control wires
that should now be used to control the Sure Power  unit.  I forget which
colour does what but one becmes 12 v positive when  the engine starts and the
alternator light goes off.  This is the 12v wire  needed to activate the Sure Power
unit at the positive position.  The  remaining third wire is a triggered
ground from the front that should now be  connected to the negative position on
the Sure Power unit.
The two red wires coming from the small fuse block  behind the drivers seat
are the positive power wires for the fridge, sink water  pump and control panel
on the sink/stove cabinet front.  Both these wires  should now be connected
directly to your aux battery positive terminal if you  want those function to
operate off your aux battery.
Hope I've been helpful and not confused you too  much.  Wiring is complex
issue to describe and I hoe I've said it all  right.  You may need to consult the
Bentley workshop manual wiring diagram  for your particular Vanagon to make
sure you know which wires do what before you  make some mistake and case
damage.  I don't always remember and I ALWAYS go  get my manual and look at the
wiring diagram when doing these installs.   Better safe than sorry !>>>>>>>>>

Cheers,

Frank  Condelli
Almonte, Ontario, Canada
_BusFusion_ (http://members.aol.com/BusFusion/bfhome.htm)  a VW Camper
camping event, Almonte, ON, June 10 ~ 13, 2004
'87 Westy & Lionel  Trains
Member: _Vanagon List_ (http://www.vanagon.com/) , _LiMBO_
(http://www.bcn.net/~limbo/) , _IWCCC_ (http://www.westfalia.qc.ca/)  & _CCVWC_
(http://www.ccvwc.ca/)
Vanagon/Vanagon Westfalia Service in  the Ottawa Valley
_STEBRO/Vanagon Stainless Steel  Mufflers_ (http://members.aol.com/
Fkc43/stebro.htm)
_Frank Condelli &  Associates_ (http://members.aol.com/Fkc43/busindex.html)
or  http://frankcondelli.com