Different Battery Setups

[dave lowry]

>Reading the various postings on battery hookups reminds me that I have
>sometimes in error made the assumption that another GMCer had the same setup
>on one system or the other as I had, but everyone should be aware that GM
>made changes in the battery placement over the various model years but also
>there was a difference in the Transmode versions and different body builders
>all seemed to have their own ideas on how to hook up the batteries. There
>are even differences in the boost switch. Some have a momentary contact
>switch and others can be left in the boost mode.
>
>Another thing, Dave, once you have the system set up as you like it, you
>should probably disconnect the Onan charging system as Duane Simmons and
>others have suggested recently.
>
>Emery Stora
>77 Kingsley
>Santa Fe, NM

Thanks Emery. I got all 4; saved the pics and printed the diagrms. Now to
go out and open some doors to see how similar mine is.

I'm pretty sure my Royale always had the back battery just for the Onan.
Since it failed so soon (2 years), I'm wondering if it might have been
relying on the Onan for its charge. I've also got to check the picture on
Gene's site and then go to see if the Onan charger has been disconnected.

I need to find out if the front to rear cable can be used to bring power to
the Onan starter. If so, we'll be able to start the onan from either or
both front battery banks or from the engine's alternator. Along with the
statpower, that would be enough redundancy to make me comfortable.

Thanks again,

Dave (advisor/navigator) & Dege (ALL else), '76 Royale, Santa Barbara, CA

 

[jerry hoxsey]

Transmode versions and different body builders
all seemed to have their own ideas on how to hook up the batteries

To add to this: Many of us have coaches that have been modified by POs with
their ideas of how it should be. For instance, my 73 has an isolator on the
onan battery so it cannot be discharged by the house system. This allows
the onan good battery source even if the engine battery and house system are
dead. I like this setup and have not changed it. I only replaced the house
12 volt battery up front with two 6 volt golf carts and left everything else
alone. By the way, in the process of checking out the system, I found one
leg of the original isolator up front was leaking. This was allowing my
engine battery to be discharged by the house system. Could be this was the
original reason the PO went to the isolator on the onan. At least he still
had the onan when all else was discharged.
Hope this all makes sense!!!!!
Jerry

 

[dave1]

Maybe someone will find this useful:

I have a 73 Sequoia that had the house batteries in the front. I added a=20
battery box in the rear for four golf-cart batteries and removed the front=
=20
batteries. I replaced the buzz-box with a solid-state charger (Todd-75)=20
adjusted for NiCad batteries. The output of the charger goes to a battery=20
isolator, one side of which is connected to the house batteries and the=20
other side to the engine battery. The battery isolator drops the charge=20
voltage from NiCad levels to Lead-Acid levels as it charges both the house=
=20
and engine batteries.

My Onan has its own battery so I ran a wire from alternator terminal of the=
=20
original battery isolator to an isolator I added in the generator=20
compartment. When the engine is running it charges the Onan battery from=20
the alternator. The additional isolator keeps the house battery and/or the=
=20
engine battery from killing the Onan battery. I kept the Onan charger=20
hooked up (probably didn't need it bit it was there).

This setup works well. If you can start either the engine or the Onan, one=
=20
can be used to charge the and start other. Same with the house batteries,=20
if you can start either the engine or the Onan you can recharge the house=20
batteries. Just a bit of redundancy that comes in handy more often than I=20
would like to admit...

Having four house batteries is nice for extended dry-camping but it also=20
results in the batteries lasting more than twice as long. I think this is=20
my 10th summer on my four Exide golf-cart batteries.

I keep it all charged up in the off-season by running the converter for an=
=20
hour a week (using a lamp timer). That tops off the batteries without=20
drying them out.

Dave
Ann Arbor, MI.
73 Sequoia (26'/455/HEI/TBI/160=B0/3.42)