Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion

   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion #1  

nsfab

New member
Joined
Oct 14, 2013
Messages
12
Location
Monroe, GA
Tractor
Ford 640
Last year I had to do some work on my tractor with it not starting and ultimately traced it down to the starter. However, I wanted to clean everything up in there as there were jumper wires going nowhere, wire nuts, etc from the previous owner. So, I am finally getting time to work on it again, and I am a tad stumped. I am trying to wire the system back up, and I am stuck on the solenoid. I have the wrong solenoid from when I ordered it last time(ford vehicle solenoid), and I am getting the proper one ordered next. But, How do I wire it up when it gets her? Here is my diagram I put together, and the questions I have are in different colors than black. I have read and read and read, and I either confused myself or I just read multiple people saying it different ways. I do not know. But any help is greatly appreciated.

 
   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion #2  
solenoid02.jpg
Just Google -how to wire up a ford solenoid. This is probably close enough (ignor the chevy starter)
 
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   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion
  • Thread Starter
#3  
Thank you for the quick response. I saw that image in my search and my question that remains is how can I wire in the neutral safety switch in series since it is a 1wire grounded connection?
 
   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion #4  
Thank you for the quick response. I saw that image in my search and my question that remains is how can I wire in the neutral safety switch in series since it is a 1wire grounded connection?
Do I assume correctly that the neutral safety switch is grounded when in the shifter it connects to is in neutral?
If so, you need a solenoid with 2 "coil" terminals, one for power and one for ground. Power connects to one "coil" terminal and the neutral safety switch connects to the other.

Aaron Z
 
   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion #5  
Yesterdaystractors.com
They have a 12v conversion kit,and the solenoid for it,and somebody on their forum can give you the wiring diagram.
 
   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion #6  
Here is a example of a solenoid with 2 "coil" terminals: Amazon.com: Ford 12 Volt SW3 Starter Solenoid Relay: Automotive one connects to power from the keyswitch and (assuming that the neutral safety switch is grounded when in the shifter is in neutral), the other one connects to the neutral safety switch.

Aaron Z
 
   / Solenoid Wiring for Ford 640 with 12v 1-Wire Conversion
  • Thread Starter
#7  
Thanks for your help guys. Got the multimeter out last night and got it figured out. Guess I did have the right one the whole time.
 
 
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