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Subject:Aux Battery
From:Wiesner Craig
Date:26 Nov 1996 11:32:40 -0800

I have been having one hell of a time with my charging system.  I hooked up a
powerful stereo to the Aux Battery under the drivers seat, as well as fog
lights and a back-up light.

Problem #1.  I can easily take out the main battery by sliding the passenger
seat back and turning it around to face the front.  How do I take out the Aux
battery?  When I turn the driver seat to the side there is still not enough
room.  The steering wheel prevents turning it towaerd the rear.  It looks like
I need to remove the seat to remove the battery.

Problem #2.  When I drive in alot of stop-n-go traffic the Aux battery was
running down to nothing.  I checked the battery. It is fine.  I put a
voltmeter on the alternator at idle and it reads 13.8v.  I put it on the posts
on the isolator and they read 12.9v! I am losing a volt in the friggin
isolator!  I tried different isolators, same result.  I then by passed the
isolator and wired the charge wires to both batteries directly to the
alternator.  This was working fine.  I figured if I stop to camp for a while I
would remove the negative post from my main to prevent drainage.  Then someone
tells me that I could blow up one of the batteries with this set-up due to
different charging needs and possible over charge of one battery.  So now I
have the main battery on the Aux post on the isolator ( supposed to be switch
on and off with the engine, 4-post isolator) and both the Aux Battery and the
alternator hooked together on the alternator post on the isolater.  Now my Aux
battery is fine, but my main is slightly under charging in stop and go!

Any suggestions or ideas?  I have read all of the posts on Aux batteries and
none has mentioned an under charging problem.  Will the batteries blow if I
leave them connected together?

Thanks,
                      - Craig

'86 Syncro Westy

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