Community Forums

GypsyTurtle · 11-17-2010, 03:58 PM

1989 Country Coach Concept
Gillig chassis

Plugged into shore power my domestic batteries read 13.5v = good
My chassis batteries need to be externally charged up to 12.5v but then over next few days discharge down (so far to 9.5v) = bad
Generator battery = not sure yet

I always assumed the Heart Interface Freedom model 20 would ALSO float charge the chassis batteries (it already does the domestic batts) - either it never did.. OR something new is wrong.

I'm wondering if my battery isolator (Powerline model 33-43) is malfunctioning. I've tried to research the 'proper' way to test this - continuity between ground and each of the 3 posts, etc... then switching my tester's leads - I want to be sure which way is right so I can know to get a new isolator or not.

thx in advance...
Jeff

Monacoach · 11-17-2010, 04:33 PM

Highly doubtful that your coach is equipped to charge engine batteries from shore power. This is generally reserved for later model coaches that have a BIRD installed. I have a 2008 model that does not have a BIRD so I am periodically using a charger to keep engine batteries fully charged. I also keep the engine battery disconnect off or disconnected so the drain is slower.

chiefdave · 11-17-2010, 04:45 PM

Monacoach, Mega Parts RV makes a dual battery isolator relay that replaces the current relay in your outside drivers compartment. It takes about 20 minutes to do the job. When your coach batteries are charged it send the charge to your engine batteries and charges them. Here's an email I received from them . The unit costs about $50 but is well worth it.

Dave
I don't know if anyone from Mega Tech sales has contacted you yet, but the upgraded version (now MT970) is available. We began delivering these last week and they are in stock. Please call 541-758-8242 and ask for Patty or send her an email at the email in the header.

Thanks.

Ron

Ron VanOrden
MEGA TECH OF OREGON
Office 541-758-8242
Fax 541-758-7639

deandec · 11-17-2010, 05:54 PM

My Freedom 25 is wired to charge only the house batteries.

You can install a Trik-L-Start to get the chassis batteries charged when on shore power or Generator power.

GypsyTurtle · 11-17-2010, 08:02 PM

Ok.. understood so far.. thanks!

but - Assuming the factory wiring is still in effect... the all-too-quick discharge of the chassis batteries could be... the isolator? The one we have installed is a dual battery setup already.. 190 amp

I see Kragen Autoparts has a 200 amp isolator for about $124. I'm afraid to buy it (in case they don't take that as a return) unless I know for sure my current isolator is bad.

Monacoach · 11-17-2010, 09:01 PM

The battery isolator separates the batteries when the engine is turned off and connects them when its running. Thats all it does so if it malfunctions such as in my case it permanently isolates the batteries which only means that the engine will not charge the house batteries. It would not affect the engine batteries. Maybe your batteries are toast.

deandec · 11-18-2010, 11:27 AM

Check the voltage at the battery terminals when the engine (alternator) is running. If you get 13.4 or so, the alternator is ok and likely so is the isolator.

If the applied charging voltage is low, clean all the battery and isolator terminals and try again. I have experienced good alternator charge but low battery measurements due to dirty connections.

It then would be time to have the chassis batteries load tested to learn their status. A truck tire shop might be able to do this with the batteries installed.

Either the alternator is not charging the batteries adequately or the batteries are at end of useful life.

Pairajays · 11-19-2010, 03:59 PM

Jeff,

I don't think you have anything wrong. It is working as designed. The isolator is only in play when the engine is running. The 1989 Concept did not come with a provision to charge the engine or generator starting batteries when on shore power. The only way to prevent these batteries from discharging is turn off the disconnect, when parked, or install a trickle charger as suggested in another post. These things are readily available from an RV supply store and cost anywhere from $50 to $100. They can be installed by almost anyone with no technical training. You connect them across the battery boost solenoid. One wire to the house battery side, another wire to the chassis battery side and the third wire to ground. Piece of cake. BTW, this does not keep the generator starting battery charged. This battery does not have any parasitic loads so it shouldn't be a problem.

Jim

Jim