Date:         Fri, 24 Mar 2006 05:25:18 -0800
Reply-To:     mark drillock <drillock@EARTHLINK.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         mark drillock <drillock@EARTHLINK.NET>
Subject:      Re: Dual battery relay blowing fuses
Comments: To: River Clan <ri@RIVERCLAN.ORG>
In-Reply-To:  <2E94389D-06FE-4409-9618-2697A8655E5D@riverclan.org>
Content-Type: text/plain; charset=us-ascii; format=flowed

Other people have reported similar problems with the low amp kits
blowing their fuses at times. I think the clue to solving yours is in
your question. You asked whether the fuse is on the battery line or the
ignition side. What do you mean "ignition side"? Exactly where are the
control leads of your relay connected? With small wires and relay like
these kits have, you must connect the control wires such that the relay
NEVER connects the batteries together while the start motor is cranking
the engine. The wire from the main battery to the starter is HUGE for a
reason. If the second battery is ever allowed to help the main battery
during starting, the wire that does so needs to be large as well, and
you need a much larger relay. The fuse supplied in the low amp kits is
critical for safety for just this reason. People hook them up "wrong".
The proper way is to use the alternator charging signal to connect the
batteries only after the engine is started and running, not to use the
ignition switch. Another way to sometimes blow the fuse even with the
relay controlled properly is by giving a jump start to another car while
yours is running.

Mark

River Clan wrote:

> I've got a GoWesty dual battery kit in my 87, and it keeps blowing
> the 30amp fuse on the relay. But not consistently, sometimes it takes
> a month. Never will do it while I have a meter out and the battery
> box open!
>
> I checked the wiring, and it's all nice, new and clean, with grommets
> going through all the metal. Would the fuse be on the battery line,
> or the ignition side?
>
> I've got the whole van tore apart currently putting in a stereo in
> it, and would love to get it fixed for good as the relay is in the
> battery box, and hard to get at.
>
> Called GoWesty, and they haven't had any troubles with the design, or
> calls from others like myself.
>
> How should I troubleshoot this?
>
> Thanks!
>
> Ri
>
>