Battery Separator works!

[Scalf77]

Canyonrover,




The picture above is the Surepower that SMB put in from 2004 to 2010?. Note the tab marked start signal. This was usually hooked up to the key switch start position. As daveb mentioned mentioned some people did not like it that way and may have wired it to a switch, in many cases a momentary switch. So if you have your key switch in the start position this wire would be high and force the solenoid closed. This would be be putting the batteries in parallel, so if you house battery was higher it would drop. If you have mystery switch, you should engage it and see what your batteries do, if the solenoid closes they should go to the same voltage. If you find that you have the wire attached to the start circuit,I am on the side of the fence that says remove it.


Also the diagram I posted in the beginning of this thread was a implementation that gets ride of the voltage monitoring part of the Surepower and just uses the solenoid. It would provide battery charging from the alternator when the engine was running, but it would not connect if plugged in, or charging the house battery with solar.

[canyonrover]

scalf77,

Thanks for the update. I will check it out and report back if I still have questions.

[daveb]

Originally Posted by canyonrover

I thought the separator was bad. That said how do you check the separator to see if it is working properly?

Sounds like it's working normally and it's tied in to the ignition. That would explain the house battery system dropping while you're starting the vehicle.
Another way to see if it's working would be to start the vehicle and remove the separators ground wire. When I was having problems with the Surepower, I pulled the ground and tapped it on the ground strip several times until it un-stuck itself. Some of the problems have been corrosion inside on the contacts and rapid operation might help. At least you'll hear it operating but you might want to ohm it out. If you do pull the ground wire and try to start the vehicle, if it struggles to start, you could have a bad starting batteries or poor cable connections provided the separator is tied into the ignition switch.

[canyonrover]

Thanks daveb. I will think it must be tied to the ignition as you say. However, there is a little bit of corrosion on the external posts of the seperator so the internal contacts might be corroded too. I will try the ground wire trick. I am thinking we are good though. I have two new starting batteries, new house battery and newly installed solar so I am just trying to understand the whole electrical picture.

Thanks,

Canyonrover

[Scalf77]

As daveb said some of us have experienced corrosion on the internal contacts. The separator will act like it has closed but you will not make contact inside. If you find this is the case you can purchase the solenoid at murcal http://shopping.murcal.com/Catalog/B...y/114-1211-020. The voltage monitoring "smarts" can be moved from old to new. Or if you are more ambitious you can open it up and clean the contacts.

-greg

Here is a post from Scatter explaining how he fixed this is issue cleaning the contacts.

I ended up with dead starting batteries just as I was leaving the house on a trip. The little jumper wire on the Sure Power box clicked in the solenoid just fine, but I still couldn't crank the engine. Got it going with jumper cables off my other rig and had no other problems on the trip. When I got home I looked into the problem. Two things needed correcting.
I posted something here on the Forum a couple of years ago about using a little jumper wire on the Sure Power to activate the solenoid and that works fine, but decided it was time to hook up something better. On my '07, SMB has it wired so that the solenoid cuts in (assuming you have the required 3 volts) when you crank the engine. That's fine if you have a gasser and just crank and go, but with an oil burner you need power when you first turn the key to ignition to heat up the glow pins before you crank the engine. On a previous starting battery failure out in the boonies I was able to get going by just cranking the engine while the glow pins were heating (that way the house battery was assisting) and got going. What I did today is to wire in a monentary push button switch on the dash. Instead of running wires all the way from under the rear seat (I've got an RB-50) I did it all under the dash. On my rig, SMB has a 15 amp fuse added right under the steering column for the circuit that activates the Sure Power during cranking. I just spliced into that wire (the side that connects to a green wire, not the one going to the ignition switch) and ran my wire from the splice to one side of the new switch and the other switch terminal to +12 volts. Lots of places to grab that under the dash on the fuse box. Now when I push my switch the solenoid kicks in and I can get house battery assist to heat the glow pins afore I crank. Works great and is a bit easier then running wires from the rear.
The other problem I was having was that even when the solenoid kicked in, I still wasn't getting any help from my house battery. I pulled the Sure Power out from under the seat and removed the solenoid from it. There are four rivits around the bottom of the solenoid that hold it together and I drilled them out. When you open it up, you'll need to unsolder the two wires from the windings so you can remove everything to get to the main terminals at the top. On mine, there was a hard, shiny green layer covering the terminals on the inside. I got out a dremel and cleaned everything up and used four #10 machine bolts to put the solenoid back together. Now I'm getting power from the house battery. I don't know what that green stuff was, but it was all over the inside of the top of the solenoid where the two large terminals come through the plastic housing.
Anyway, I suggest all of you pull the wires off one side of the top of the solenoid and check the continuity across the two terminals when it's activated. Mine was almost totally open and that's why my two batteries weren't helping out each other. This also keeps the alternator from charging the house battery and my solar from charging the starting batteries. Same when you plug into shore power. I've had similar problems on other solenoids. Just cause it clicks doesn't mean there's a connection.
___________________
Scatter

2007 RB50, 6.0
K1WGB