battery isolator
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Elder User
Joined: Sep 2000
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From: Golden ,CO USA
battery isolator
does anyone know how a dual battery isolator is supposed to be wired???? i have dual batteries in my truck and the secondary one never charges so i am going to ommit the isolator if i cant fuirer out how it is sopposed to be wired into the system. right now there is 2 wires going to the isolator from the alternator and one going from the isolator to my secondary battery.
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
Posting Guru
Joined: Jun 1999
Posts: 2,415
Likes: 3
From: Comox Valley, Canada
battery isolator
There should be three posts on the battery isloator, with one wire on each post.
The alternator wire should go to the centre post of the isolator. Then a wire going from the right post of the isloator to the main battery or secondary battery (doesnt matter which), and the other battery should be connected to the left post of the isolator.
If you want to remove the isloator you should really remove the secondary battery as well. Sometimes two batteries hooked up direct to the alternator do not charge very well.
Sparky
The alternator wire should go to the centre post of the isolator. Then a wire going from the right post of the isloator to the main battery or secondary battery (doesnt matter which), and the other battery should be connected to the left post of the isolator.
If you want to remove the isloator you should really remove the secondary battery as well. Sometimes two batteries hooked up direct to the alternator do not charge very well.
Sparky
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Elder User
Joined: Sep 2000
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From: Golden ,CO USA
battery isolator
thats how i thought it should be hooked up. now my next question is seems how there are 2 wires comming fron the alternator to the isolator, whick on estays and wich one goes. and where it goes too.
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
Thread Starter
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Elder User
Joined: Sep 2000
Posts: 718
Likes: 0
From: Golden ,CO USA
battery isolator
im thinking that it should go to the solenoid cause the book says that wire is sopposed to go to it. but which post does it go to on the solenoid????
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
Posting Guru
Joined: Jun 1999
Posts: 2,415
Likes: 3
From: Comox Valley, Canada
battery isolator
Does this mean that there is a post on the islolator not being used ??
The two wires from the alternator could have been installed to handle the current flow instead of one larger wire.
If both wires go direct to the alternator + from the centre post of the isolator they can both stay. 2 smaller wires are as good as 1 larger wire, like 2 #12 wires as good as 1 #8 wire, and they are easier to work with than 1 large wire.
Sparky
>thats how i thought it should be hooked up. now my next
>question is seems how there are 2 wires comming fron the
>alternator to the isolator, whick on estays and wich one
>goes. and where it goes too.
>
>'75 F-100 4x4, 4" lift
>16x38.5x15 super swamper TSL
>390 w/ cam,headers,
>and 4 barrell edelbrock
>
>TRIED TRUE and FORD BLUE
The two wires from the alternator could have been installed to handle the current flow instead of one larger wire.
If both wires go direct to the alternator + from the centre post of the isolator they can both stay. 2 smaller wires are as good as 1 larger wire, like 2 #12 wires as good as 1 #8 wire, and they are easier to work with than 1 large wire.
Sparky
>thats how i thought it should be hooked up. now my next
>question is seems how there are 2 wires comming fron the
>alternator to the isolator, whick on estays and wich one
>goes. and where it goes too.
>
>'75 F-100 4x4, 4" lift
>16x38.5x15 super swamper TSL
>390 w/ cam,headers,
>and 4 barrell edelbrock
>
>TRIED TRUE and FORD BLUE
Posting Guru
Joined: Jun 1999
Posts: 2,415
Likes: 3
From: Comox Valley, Canada
battery isolator
If you mean the starter solenoid, then the wire from the isolator to the main battery should go to the large post of the starter solenoid that the battery positive wire goes to.
Sparky
>im thinking that it should go to the solenoid cause the book
>says that wire is sopposed to go to it. but which post does
>it go to on the solenoid????
>'75 F-100 4x4, 4" lift
>16x38.5x15 super swamper TSL
>390 w/ cam,headers,
>and 4 barrell edelbrock
>
>TRIED TRUE and FORD BLUE
Sparky
>im thinking that it should go to the solenoid cause the book
>says that wire is sopposed to go to it. but which post does
>it go to on the solenoid????
>'75 F-100 4x4, 4" lift
>16x38.5x15 super swamper TSL
>390 w/ cam,headers,
>and 4 barrell edelbrock
>
>TRIED TRUE and FORD BLUE
Thread Starter
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Elder User
Joined: Sep 2000
Posts: 718
Likes: 0
From: Golden ,CO USA
battery isolator
the two wires coming fronm the alternator go to two different posts on the isolator. the one in the middle and the one on the left. im going to remove the one off the left post and put it so it hjooks up to the starter solenoid and hook my primary battery to that post on the isolator.
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
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Posting Guru
Joined: Jun 1999
Posts: 2,415
Likes: 3
From: Comox Valley, Canada
battery isolator
Are you sure both wires go to the alternator??? 
Before you start swapping wires around make sure you know where they go and what will happen if you move them. Bad things can happen if they are hooked up wrong. Well bad unless you like smoke and flames coming from your truck
Sparky
Before you start swapping wires around make sure you know where they go and what will happen if you move them. Bad things can happen if they are hooked up wrong. Well bad unless you like smoke and flames coming from your truck
Sparky
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New User
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battery isolator
Please have a look at my prehistoric drawing to see if it helps you.
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=672&.jpg
I don't know where you got a second wire coming to the isolator that isn't battery or alternator related.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=672&.jpg
I don't know where you got a second wire coming to the isolator that isn't battery or alternator related.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
New User
Joined: Jan 2008
Posts: 0
Likes: 24
battery isolator
[updated:LAST EDITED ON 27-Dec-01 AT 07:39 PM (EST)]>the two wires coming fronm the alternator go to two
>different posts on the isolator.
There should only be ONE wire going from the alternator to the center terminal of the isolator.
*Note :
a)One wire from the Center post of the isolator to the alternator.
b)One wire from and End isolator connection to the + battery post side of the starter solenoid.
c)One wire from the other end terminal of the isolator to the Auxillary battery + post.
d) BOTH Batteries have to be grounded to charge.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
>different posts on the isolator.
There should only be ONE wire going from the alternator to the center terminal of the isolator.
*Note :
a)One wire from the Center post of the isolator to the alternator.
b)One wire from and End isolator connection to the + battery post side of the starter solenoid.
c)One wire from the other end terminal of the isolator to the Auxillary battery + post.
d) BOTH Batteries have to be grounded to charge.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
Thread Starter
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Elder User
Joined: Sep 2000
Posts: 718
Likes: 0
From: Golden ,CO USA
battery isolator
thats how i thought it was sopposed to be hooked up. and there is two wires connecting the alternoator and isolator. thanks for the drawing. ill hook it up the correct way this weekend.
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
Thread Starter
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Elder User
Joined: Sep 2000
Posts: 718
Likes: 0
From: Golden ,CO USA
battery isolator
i just have to fuiger out where that other wire goes to
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
New User
Joined: Jan 2008
Posts: 0
Likes: 24
battery isolator
What colour is it and is it part of the Ford Harness or an aftermarket wire?
Some people put the electric choke wire on these too.
Why ,I don't know.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
Some people put the electric choke wire on these too.
Why ,I don't know.
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
Thread Starter
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Elder User
Joined: Sep 2000
Posts: 718
Likes: 0
From: Golden ,CO USA
battery isolator
[updated:LAST EDITED ON 27-Dec-01 AT 10:26 PM (EST)]its a black wire (not factory)the same size as the one going to the center post on the isolator. ill have to look at which post on the alternator its on. maybe that will tell me where it is sopposed to go and hook up to.
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
'75 F-100 4x4, 4" lift
16x38.5x15 super swamper TSL
390 w/ cam,headers,
and 4 barrell edelbrock
TRIED TRUE and FORD BLUE
New User
Joined: Jan 2008
Posts: 0
Likes: 24
battery isolator
Here's a NORMAL charging system diagram for you to look at.
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=364&.jpg
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles
https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=364&.jpg
Dennis
78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles