No flames intended here Harold. I'm certainly no expert on this topic,
though I do have some experience with it. Just wanted to add the following
points to this discussion:

" I believe the factory
>relay under the front seat that most westies have is designed
>by VW to only power the refrigerator 12 volt heating element.
>There is a possibility that, if one is using that to also charge a
>second battery, that the relay or the wiring could be damaged."

Actually, if you look at the wiring diagram on page 97.222 of the Bentley
you will see that the relays that came on Vanagons from 1986 were ment to
work with an auxillary battery. Weather the stock wiring was adequately
designed or not I don't know. I do know that this set up seems to work fine
on my 90 Westy Syncro.

"It is fuse protected, but still....
>That setup works for a lot of people, but it is good to at least
>keep an eye on it. Imho."

Not a bad Idea!

"On the setup I am using, the deep cycle battery is under the drivers seat,
>and I >mounted the isolator in the engine compartment behind the right
>rear wheel well."

Don't know if this is a good idea or not. Those fins on the isolator are
there for a reason: to disperse heat. The engin compartment is a pretty warm
place. My guess is that you could mount the isolator anywhere that is not
hot if you use large enough wire. I would refer you to the tech support
number on the isolator instructions for this one.

Thanks for listening,
Bill
90 Westy Syncro

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