Onan/House battery

[duane m simmons]

Dave
I think if you look closely you will find that Coachman set up two House
Batteries (one in front & one in rear) in Parallel that are also the Onan
Starting Battery. The fact that the rear battery is getting a charge
from the Engine Alternator tells me that this is still the arrangement of
batteries. This is not at all a desirable way to set up the House/Onan
battery with two batteries in parallel. Best to disconnect & eliminate
the Golf Cart batteries up front with their cables & move the Golf Cart
Batteries to the rear & have one House/Onan (yes the will fit w/4 or 6KW
Onans). Having one 12 volt battery Pack in the rear near the Onan & near
the House DC distribution bus is highly desirable.
Works for me with 2 weeks of dry camping w/o battery concerns or
limitations. A good battery cable connection is necessary at the
batteries as well as at the chassis ground connection. Also a cleanup of
the Steel Frame to Aluminum Frame ground cable connection is highly
desirable (front passenger side frame to aluminum floor support). Adding
an additional ground cable between the Engine Ground cable to the steel
chassis frame will allow all batteries to be charged/discharged via the
same ground reference (good charge capability).
Call me Dave if this is not clear & additional information is desired.

Duane of Orange, CA
714-633-4731

 

[dave lowry]

>Dave
>I think if you look closely you will find that Coachman set up two House
>Batteries (one in front & one in rear) in Parallel that are also the Onan
>Starting Battery. The fact that the rear battery is getting a charge
>from the Engine Alternator tells me that this is still the arrangement of
>batteries. This is not at all a desirable way to set up the House/Onan
>battery with two batteries in parallel. Best to disconnect & eliminate
>the Golf Cart batteries up front with their cables & move the Golf Cart
>Batteries to the rear & have one House/Onan (yes the will fit w/4 or 6KW
>Onans). Having one 12 volt battery Pack in the rear near the Onan & near
>the House DC distribution bus is highly desirable.
>Works for me with 2 weeks of dry camping w/o battery concerns or
>limitations. A good battery cable connection is necessary at the
>batteries as well as at the chassis ground connection. Also a cleanup of
>the Steel Frame to Aluminum Frame ground cable connection is highly
>desirable (front passenger side frame to aluminum floor support). Adding
>an additional ground cable between the Engine Ground cable to the steel
>chassis frame will allow all batteries to be charged/discharged via the
>same ground reference (good charge capability).
>Call me Dave if this is not clear & additional information is desired.
>
>Duane of Orange, CA
>714-633-4731

Duane, If the 2 banks were wired in parallel and the rear battery was no
good, wouldn't that seriously reduce the overall capacity of the house
batteries (by only allowing charge to the capability of the weakest
battery)? We haven't noticed any change.

I'm not at all sure the rear battery is being charged by the alternator.
I'll have my non-technical helper check it out provided there's an easy
enough way that I can walk him through it. Of course, if it turns out the
Onan's VR has been disconnected (haven't looked yet), I'll know its being
charged by the alternator.

Moving the 2 6v house batteries to the Onan compartment makes good sense.
It would lighten the load up front and still make room to store some oil &
stuff. Unfortunately, time and budget constraints dictate that project's
delay until after this next trip. In the interim, would changing the wiring
to allow the Onan to be started by either of the front banks be easy enough
that my helper could be talked through it? If not, we'll just have to fire
the Onan from the alternator 'til we get back in July.

Sure appreciate the help.

ps: I'd have called, but figured others might have similar concerns and
benefit from the discussion.

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