800 Ford starter wiring

[Nate Marvin]

I have a 850 Ford tractor that has been converted to 12 volts. Previous owner had a momentary push button to activate the solenoid , to activate starter. I want to know if I can wire the original push button on the top of the transmission cover to engage the starter? It of course was originaly 6 volt positive ground, I have tried different solenoid and a SPDT relay to no avail. Any help would be appreciated.
 

[Steve@Advance]

Welcome Nate!

Yes you can use the original start switch, and it will also give you the neutral safety feature, which can be a life saver!

How it works, the original switch provides a ground circuit for the solenoid. You can test the switch by connecting an ohm meter between the post and ground. It should show continuity to ground when pushed.

But, to make it work, it takes a special solenoid. It looks just like a regular automotive solenoid, but instead of the energizing coil grounding through the bracket, the coil uses the 2 small terminals.

You can connect one small terminal to the ignition circuit (so it can't be cranked with the ignition off), the other terminal connects to the neutral/start switch, which provides the ground for the solenoid coil.
Solenoid

 

[Bob]

You need the correct starter solenoid that has an internal connection between it's coil and the battery-side stud on the solenoid. (Specific to Ford tractors and vehicles of that era.)

When the pushbutton tranny-top switch grounds the little third terminal, the solenoid "pulls in" and operates the starter.

Or, if you already have a newer-style solenoid and an little relay, that should be easy to set up, as well.



This will give the added benefit that the starter will not operate unless the keyed ignition switch is "ON", AND the neutral safety pushbutton is depressed.


 

[Nate Marvin]

Thank-you. I have a couple new ideas to try now.
 

[Nate Marvin]

[quote="Nate Marvin"](quoted from post at 22:19:33 12/25/1
Thank-you. I have a couple new ideas to try now.[/quote

Just got home and time to mess with the Ford tractor. I wired the Bosch relay just like you said to and everything works like it's supposed to. Thanks for your help. Was starting to pull my hair out.
Nate
 

[Nate Marvin]

[quote="CVPost-Steve@Advance"](reply to post at 17:03:32 12/25/1 [/quote

Thanks for your help Steve.
 

[Bob]

GLAD to hear it worked for you!

Now you have the added safety feature that the starter will not engage unless the keyed ignition switch is "ON".

And THANKS for posting back!