battery changeover system

[sbb2112]

I just got a 1977 Itasca c22c and after an 2 entire days unwiring the P.O. or owners handy wiring job(s), I have gotten down to what matches the factory wiring diagram for everything but this system. I have two batteries, the solenoid on the firewall (appears to be stuck in the contacted position) and thats it. There are cut off wires overhead of the windshield rear view mirror (4 in a ribbon and 3 separate ones). I believe I am missing everything else. The white wire from the solenoid was wired directly into a hot in run terminal in the fuse panel under the dash. I was hoping to put things back in order or at the least not have the solenoid hard wired on all the time. I don't have any switches, voltmeter, generator switches or the generator for that matter. Has anyone any suggestions on parts or a safe way to hook up the dual battery setup? I have every other system straightened out and working. Lights, converter, fridge, etc all fine.

[gadgetman]

This post may help you

http://www.classicwinnebagos.com/forum/index.php?topic=6184.0

[sbb2112]

That was a very informative post and so I called around and found a battery isolator but its different than the three post original. It has 4 terminals #1 battery, #2 battery, switched ignition wire and one for connecting to the alternator (I am assuming a sense wire). I have yet to try to hook it up and as I can't return it if I try, was wondering if anyone had used one like this? I had to charge the chassis battery last night as it was dead. The house battery was at ~12.8.

[DaveVA78Chieftain]

Your rig should have a SI style alternator (pre-86) which requires the 3 post verison.  The 4 post version is used with a CS style alternator (86 & later).
Those isolators only charge chassis and coach batteries when the engine is running.  They do not work in the reverse direction for using the converter to charge the chassis battery.  Use a Trick-L-Start to use the converter to charge the chassis battery.

Dave

[sbb2112]

That is correct, SI style. I found a 3 post at NAPA but they had to ship it in. I guess I will do that. Thanks a bunch!!