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Battery isolator bad? [message #123643] Thu, 28 April 2011 12:09 Go to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
I am almost certain that my isolator is bad. It fails to charge the engine battery when hooked up to shore power. Charges the house batteries just fine. If I put a jumper across the solenoid, it will charge the engine battery when hooked to shore power, so I know the charger/inverter is working. I have a combiner that I bought 6 yrs ago and just have not installed it. Do I need to have a good working isolator so that the isolator will work, or should I replace the combiner and then install the isolator?
Thanks


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: Battery isolator bad? [message #123644 is a reply to message #123643] Thu, 28 April 2011 12:11 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
Karma: 10
Senior Member
Larry wrote on Thu, 28 April 2011 12:09

I am almost certain that my isolator is bad. It fails to charge the engine battery when hooked up to shore power. Charges the house batteries just fine. If I put a jumper across the solenoid, it will charge the engine battery when hooked to shore power, so I know the charger/inverter is working. I have a combiner that I bought 6 yrs ago and just have not installed it. Do I need to have a good working isolator so that the isolator will work, or should I replace the combiner and then install the isolator?
Thanks


Last sentence was to say "Do I need to have a good working isolator so that the combiner will work, or should I replace the combiner and then install the isolator?


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] Battery isolator bad? [message #123647 is a reply to message #123643] Thu, 28 April 2011 12:19 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member

On Apr 28, 2011, at 11:09 AM, Larry wrote:

>
>
> I am almost certain that my isolator is bad. It fails to charge the engine battery when hooked up to shore power. Charges the house batteries just fine. If I put a jumper across the solenoid, it will charge the engine battery when hooked to shore power, so I know the charger/inverter is working. I have a combiner that I bought 6 yrs ago and just have not installed it. Do I need to have a good working isolator so that the isolator will work, or should I replace the combiner and then install the isolator?
> Thanks
> --
> Larry :)
> 78 Royale w/500 Caddy
> Menomonie, WI.
>

Larry

The engine battery will never charge from the standard GM built setup when hooked to shore power.
The only way you can do it is to jumper the solenoid. Your isolator sounds fine and is working as it should.
The isolator takes power from the alternator when the engine is running and feeds it to both the engine and the house battery.
When plugged into shore power there is no connection to the engine battery.

More modern converters that replace the buzz box such as the Xantran Statpower 40+ that I have has an additional output that can be run to the engine battery by adding a wire and then that will charge the engine battery.

Normally you should not have to charge the engine battery as it is kept up to charge when the engine is running.

if you are running such things as the dash radio when parked it will run down the engine battery. You can change that so it runs off the house batteries.

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: Battery isolator bad? [message #123649 is a reply to message #123643] Thu, 28 April 2011 12:39 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Larry, like Emery said, your isolator is working like it was designed to work. You do not need a working isolator to use the combiner. I am one who prefers not to use both. I have two combiners on our coach. One up front and one for my Onan motorcycle starting battery.
I kept blowing the small combiners and had to upgrade to a larger one, up front. No problems with it.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Battery isolator bad? [message #123654 is a reply to message #123644] Thu, 28 April 2011 13:21 Go to previous messageGo to next message
Billy Massey is currently offline  Billy Massey   United States
Messages: 916
Registered: January 2004
Location: Central Texas
Karma: 1
Senior Member

Your isolator is working as it should if it charges your house batteries
while under way. It is not meant to charge your chassis battery.

You don't need an isolator with your combiner but it doesn't hurt to have
both. I've done it both ways but to retain the isolator has its advantages.
See Gene's album: www.gmcmhphotos.com/photos/showgallery.php?cat=4944

bdub


-----Original Message-----
From: Behalf Of Larry

Larry wrote on Thu, 28 April 2011 12:09
> I am almost certain that my isolator is bad. It fails to charge the engine
battery when hooked up to shore power. Charges the house batteries just
fine. If I put a jumper across the solenoid, it will charge the engine
battery when hooked to shore power, so I know the charger/inverter is
working. I have a combiner that I bought 6 yrs ago and just have not
installed it. Do I need to have a good working isolator so that the
isolator will work, or should I replace the combiner and then install the
isolator?
> Thanks


Last sentence was to say "Do I need to have a good working isolator so that
the combiner will work, or should I replace the combiner and then install
the isolator?
--
Larry :)
78 Royale w/500 Caddy
Menomonie, WI.


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bdub
bdub.net
Re: [GMCnet] Battery isolator bad? [message #123655 is a reply to message #123654] Thu, 28 April 2011 13:38 Go to previous messageGo to next message
Billy Massey is currently offline  Billy Massey   United States
Messages: 916
Registered: January 2004
Location: Central Texas
Karma: 1
Senior Member

Ooops! Should be "It is not meant to charge your chassis battery "when
plugged into shore power".



-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Billy Massey
Sent: Thursday, April 28, 2011 1:22 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Battery isolator bad?

Your isolator is working as it should if it charges your house batteries
while under way. It is not meant to charge your chassis battery.

You don't need an isolator with your combiner but it doesn't hurt to have
both. I've done it both ways but to retain the isolator has its advantages.
See Gene's album: www.gmcmhphotos.com/photos/showgallery.php?cat=4944

bdub


-----Original Message-----
From: Behalf Of Larry

Larry wrote on Thu, 28 April 2011 12:09
> I am almost certain that my isolator is bad. It fails to charge the engine
battery when hooked up to shore power. Charges the house batteries just
fine. If I put a jumper across the solenoid, it will charge the engine
battery when hooked to shore power, so I know the charger/inverter is
working. I have a combiner that I bought 6 yrs ago and just have not
installed it. Do I need to have a good working isolator so that the
isolator will work, or should I replace the combiner and then install the
isolator?
> Thanks


Last sentence was to say "Do I need to have a good working isolator so that
the combiner will work, or should I replace the combiner and then install
the isolator?
--
Larry :)
78 Royale w/500 Caddy
Menomonie, WI.


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bdub
bdub.net
Re: Battery isolator bad? [message #123797 is a reply to message #123643] Fri, 29 April 2011 10:45 Go to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Just consider the isolator as part of the alternator charging system. If the alternator charges BOTH batteries (House and engine then the isolator is doing it's job.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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