Date: Mon, 15 Mar 2004 13:08:52 -0500
Reply-To: Joy Hecht <jhecht@ALUM.MIT.EDU>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Joy Hecht <jhecht@ALUM.MIT.EDU>
Subject: more on problems with second battery
In-Reply-To: <28.44d813f1.2d86fe98@aol.com>
Content-Type: text/plain; charset="us-ascii"
Thanks very much to everyone who provided all the details on our problems
with the isolator.
It looks like there are two reasonable choices open:
- Exchange the Sure Power isolator for a Sure Power separator and install
that. I don't know how much the separator costs - I assume it's in the same
range as the isolator ($70). It sounds from some of the emails like it may
be easier to install, because we can do it between the two batteries and
don't have to rewire to the alternator, but I'm not sure if I've got that
right.
- Return the isolator (the RV place said if it's in good shape, which it
should be, they'll give me most of my money back) and buy the Hella relay
kit that Busdepot sells for $20. Some people have sworn by the Hella kit,
others have said the separator would be better.
I'd appreciate anyone's knowledge of pros and cons of the two options,
particularly regarding:
- ease of installation - what we have to be able to access to wire it,
whether we can use the setup we already organized - Optima battery in its
hole, separator or relay in the cabinet under the sink, wires running under
the carpets from batteries to sink), and
- performance - does one setup or the other have significantly better
power management characteristics or less waste or not recharge fully enough
or other things?
And another question - I now have some understanding of what a diode is, and
therefore what an isolator does. If anyone could explain to me - on about
the level of a high school shop course - how relays and separators work, I'd
appreciate it!
Oh, and for all who said I need the Bentley - yes, yes, I'm ordering it
today.
Joy
-----Original Message-----
From: RAlanen@aol.com [mailto:RAlanen@aol.com]
Sent: Monday, March 15, 2004 7:42 AM
To: vanagon@gerry.vanagon.com
Cc: jhecht@alum.mit.edu
Subject: Re: problems installing second battery
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 with 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 plate 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 a VW Camper camping event, Almonte, ON, June 10 ~ 13, 2004
'87 Westy & Lionel Trains
Member: Vanagon List, LiMBO, IWCCC & CCVWC
Vanagon/Vanagon Westfalia Service in the Ottawa Valley
STEBRO/Vanagon Stainless Steel Mufflers
Frank Condelli & Associates or http://frankcondelli.com
