Simple Wiring Issus on Ford 2000 (Pre 1964, 4 Cyl)

[Soundguy]

ground polarity makes -0- difference to a switch or relay.. you do realize that don't you?

the ford tractor start relay 3 wire and 4 wire are very, very, very , very common. the 6v versions work JUST fine on 12v.

one lil terminal to switched power.. other lil terminal to that trans top button.

Using Standard Ignition as an example:
Original-style 6 Volt isolated base solenoid, # SS-572.

12 Volt version... # SS-567. ($15.25 on-line.)

the napa / echlin number that will work is: Echlin ST542

 

[Randa]

ground polarity makes -0- difference to a switch or relay.. you do realize that don't you?

I thought I did........I don't understand why my tractor wired like the original diagram isn't working. You said my solenoid was the issue but I guess that's what I don't understand. What is the difference between my identical auto zone solenoid and the solenoid you just recommended? It just seems so easy in my head but then it doesn't work....ya, who am i fooling....apparently I don't get it.

 

[byronlj]

Randa,
The image in the upper right hand corner of the attachment shows the internal coil of the solenoid energized by grounding through the switch (what you need). A typical automotive solenoid is not built anything like this. All the connections are for positive voltage. I would recommend finding a solenoid with one of the part numbers that Soundguy provided.

Dave

 

[Soundguy]

I thought I did........I don't understand why my tractor wired like the original diagram isn't working. You said my solenoid was the issue but I guess that's what I don't understand. What is the difference between my identical auto zone solenoid and the solenoid you just recommended? It just seems so easy in my head but then it doesn't work....ya, who am i fooling....apparently I don't get it.

lets look at 4 post solenoids. inside the solenoid is a electromagnet to make the contacts move.

the big conenctions are easy. starter and battery.

the little connections are what makes the difference.

in those tractor solenoids, the 2 small connections are what connects to the electromagnet. so one small connection needs ground, one small connection needs power. turning on key is the power, pressing the thumb button is the ground. polarity don't matter, and 6v solenoids will run on 12v ( low duty cycle )

Now.. modern car solenoids are wired different.

2 big posts still the same... bat and starter.

the lil posts are tricky. the electromagnet is wired between 1 little post, and the mounting leg on the solenoid. the mount leg on the solenoid is obviously used to mount the device to the starter or other metal part. that means the electromagnet is grounded already. as soon as the correct little post gets power from the key, it engages. the 2nd little post on the auto solenoid is normally open, but connected to battery when the other post is getting key power, this lil post is uses to bypass ignition resistors to give a coil full power at startup.

pre 65 fords use the isolated base solenoids.