Cascade Crew

aaron_sK · Posted: Tue May 04, 2010 6:24 pm Post subject: Dual battery madness

So the big diesel Furd has dual batteries in it. Not sure if it's parallel or sequential, or whatever you would call it, but basically the positive goes from one batt. to the other, and then to the starter solenoid, and both negs go to the block.

Previous owner put some reman Budget Battery units in there. They start the truck. Shrug

But I have this nice little Exide Orbital sitting around the shop that's been following me for years now. I've abused it more than I want to think about, and it strikes me that this little champ should probably make it's way into the Ford.

Problem is I'm not sure if I'd crap anything up running a regular battery alongside the deep cycle. If not, does it matter whether it's the one closer or farther from the starter?

Thanks guys.

chevymad · Posted: Tue May 04, 2010 6:43 pm Post subject:

The batteries are hooked up in parallel. You really only want batteries of the same type and vintage. With this system when one battery goes bad it takes the other with it eventually.. Your orbital has different charging requirements and internal voltages, I really think you should save it for something else.

Now if you had 2 of them.. we've dont that alot for emergency vehicles.

Al Hasse · Posted: Tue May 04, 2010 6:51 pm Post subject:

That increases the overall current output (amps) while maintaining 12 volts. Great for rolling over that starter. Brandon is right, you want them to be the same.

aaron_sK · Posted: Tue May 04, 2010 7:00 pm Post subject:

Thanks guys. Looks like I'm in the market for another deep cycle Orbital then. Very Happy

RSFreak · Posted: Wed May 05, 2010 9:20 pm Post subject:

How is the alternator hooked up? To both batteries or just one?

chevymad · Posted: Wed May 05, 2010 9:31 pm Post subject:

Batteries are hooked up in parallel.. so they act as one 12v battery. All draw and all charging go to both.

It's a diesel thing, its just to increase cranking amps to get them to spin over fast enough to start.

IROCDave · Posted: Thu May 06, 2010 4:03 pm Post subject:

It's not just cranking amps. Most deisels will not run unless both batterys are in good shape. On my Duramax, one battery powers the starter, the other is for the grid heater and the rest of the truck. It will not start without 12 volts from each. A guy I work with had one battery go bad on his 02 powerstroke in the parking lot at work. We tried jumping it with mine, didnt work, then took one battery from my rig and used it to start his truck. When we disconnected my battery from his truck it died.

Twilightoptics · Posted: Thu May 06, 2010 4:08 pm Post subject:

Problem is when one goes bad, it drags the other one down big time.

chevymad · Posted: Thu May 06, 2010 4:53 pm Post subject:

Old fords like his will run with just 1 battery if it has enough power to crank it. Very hard on the battery and the cables though. With both batteries in there the load is shared by both batteries and both sets of cables. This setup just has a major cable connecting the positives of both batteries and then seperate grounds to the engine block. So the batteries are NOT seperated at all and work as one large battery.

rjmcgee · The Hammer Joined: 08 Jan 2004 Posts: 2328

aaron_sK · Posted: Thu May 06, 2010 7:26 pm Post subject:

Al Hasse · Posted: Thu May 06, 2010 9:05 pm Post subject:

I don't know what gauge yours is, but welding cable works pretty well, very flexible and relatively inexpensive. I used a piece with the appropriate ends soldered and shrink-wrapped on for my positive battery cable (it's either 2 or 0 AWG IIRC).

aaron_sK · Posted: Thu May 06, 2010 9:14 pm Post subject:

It looks to be about a 2ga wire, Al, although I wouldn't mind an upgrade. Only problem being my soldering iron and crimpers lack the balls to do anything more than around 8ga wire.

chevymad · Posted: Thu May 06, 2010 9:16 pm Post subject:

Wire that heavy you need a torch.

aaron_sK · Posted: Thu May 06, 2010 9:19 pm Post subject:

chevymad · Posted: Thu May 06, 2010 9:21 pm Post subject:

No.. just get things hot, then apply the solder.

Al Hasse · Posted: Thu May 06, 2010 9:23 pm Post subject:

aaron_sK · Posted: Thu May 06, 2010 9:40 pm Post subject:

Sweet.

Thanks guys. Have to whip up some wires, and start another rewiring project. Every freakin' car I buy has the worst wiring hackjob from the previous owners. #$%^&*

Dewey316 · Posted: Thu May 06, 2010 10:03 pm Post subject:

The trick I found, is to melt a little solder into the terminator end, and put some on the wire, then heat the termintor up while you hold it with pliers, until the solder melts and the wire pushes in, then hold and let it cool for a couple of minutes.

rjmcgee · The Hammer Joined: 08 Jan 2004 Posts: 2328

Have to find the appropriate battery terminal for the passenger side battery. The cable goes in one side and back out the other. That is why I just went to Ford and got a new one when my terminal split in half. Don't get too hillybilly happy on this one. I fight corrosion on my winch connections several times a year. Something about it just corrodes constantly. I'm gonna be changing both of my batteries this summer with Optima red tops and then run chevy side terminal cables to my winch. Between the dry cells and side terminals corrosion should be a thing of the past.

I'll also add from experiance keep the starting, charging, and glow plug systems working.

Years ago I was working alone up in the mountains one day in the winter. I had been fighting my glowplugs for a few days, but just used the block heater at night. It was a cold day and late in the afternoon my 89 7.3 wouldn't start. Tried everything, had a log skidder there so I kept the jumper cables hooked up and would try to start it every few minutes. Finally it's getting dark and I got desperate and gave her a little snort of either, fired right up. 3 weeks later that sucker blew up with a beautiful display of smoke and steam. Had I just fixxed a few glow plugs I could have saved alot of money.