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Old Dec 3, 2009 | 08:46 PM
  #1  
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Explain Battery/Electrical

OK i am a little confused about the electrical system of our trucks.
2 batteries, are they in series or parallell

Is the starting system 24 and the rest of the truck 12?

i have a little battery maintainer that i have always use to trickle my batteries to peak charge state. Can i hook it up to each battery to peak or do i have to disconnect one of them since the charger is 12 volts.

thanks
 
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Old Dec 3, 2009 | 08:50 PM
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They are in parallel -- everything is 12V. Anything you hook to one battery is connected to the other one, so if you want to trickle charge both, just hook to one. The other will get it too.
 
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Old Dec 3, 2009 | 09:40 PM
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If everything is 12V, why have 2 batteries?
 
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Old Dec 3, 2009 | 09:42 PM
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Have two batteries for more AMPS not volts
 
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Old Dec 3, 2009 | 10:35 PM
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Takes a lot of amps to crank these motors!
 
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Old Dec 3, 2009 | 10:38 PM
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Originally Posted by TxFordGuy
If everything is 12V, why have 2 batteries?
Big engines with much higher compression than a gas motor, so it takes more amps to spin the starter.

In addition, the glow plug system draws a lot of amps.

When you crank the truck, both the starter and glow plugs are working. A single batter can't provide enough amps to power it all and get the truck running.

However, there are a few people out there who have bought one single large battery. IIRC, Joey at Terminator Engineering did this with his OBS truck using a gel battery.

So it can be done. It's just that for most people, especially in cold climates, having two batteries is more reliable, hence why Ford put them in.
 
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Old Dec 4, 2009 | 12:08 AM
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To give you an idea of what it takes to start these beasts, heres a post of mine from a year ago. The OP asked what the max amp draw on start up was.

For a 2001 diesel starter:
No load amps 170 max
Normal cranking is 230-630 amps
Max load (stalled) is 2400 amps.

Add in the glow plugs and I'd guess around 800-1000 amps depending on the battery's age.
 
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Old Dec 4, 2009 | 12:16 AM
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Originally Posted by Pocket
Big engines with much higher compression than a gas motor, so it takes more amps to spin the starter.

In addition, the glow plug system draws a lot of amps.

When you crank the truck, both the starter and glow plugs are working. A single batter can't provide enough amps to power it all and get the truck running.

However, there are a few people out there who have bought one single large battery. IIRC, Joey at Terminator Engineering did this with his OBS truck using a gel battery.

So it can be done. It's just that for most people, especially in cold climates, having two batteries is more reliable, hence why Ford put them in.
That is so weird I was going to use Joeys truck as an example of a single batt truck then read your post Great minds think alike
 
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