Ford 4000 S-O-S ignition help

[kuschneider]

OK,

I am trying to figure out why my tractor will not crank via the push to start button. Here is what I know and have done.

Yes the tractor Runs. I hot wire the tractor from a battery + to the ignition coil and starter nut, and batter (-) tractor frame and it starts

The push button switch has continuity. My toggle switch was bad, I just have those wired taped right now.

I have continuity everywhere I should ( I think). My gut tells me this is a lack of ground issue.

See my simplistic picture below. My starter will turn if I run a jumper between

1--> 4 (duh)
1-->3
2-->3

I was in the process of cleaning/tighenting all connections and the lower of the two smaller terminals on the starter solenoid busted. I know I need a new one, but I would like to know
a) was the current one already bad
b) what is the correct solenoid to order
3) OR is this not grounding because of the neutral safety switch?

 

[Soundguy]

You are proving that 3 needs to be hot to start the machine, not counting jumping 1-4 to straight bypass the relay.

That tells you the push button switch connected to 3 needs hot, not ground.

I'm on a phone at a gig and away from my manuals to look at the SOS ns start switch wiring.

But that gives you one more troubleshooting step for the push button switch.

 

[kuschneider]

You are proving that 3 needs to be hot to start the machine, not counting jumping 1-4 to straight bypass the relay.

That tells you the push button switch connected to 3 needs hot, not ground.

I'm on a phone at a gig and away from my manuals to look at the SOS ns start switch wiring.

But that gives you one more troubleshooting step for the push button switch.

So you saying that the wiring to the push button is bad, or I am making a false assumption that it should be ground. I can only find generic wiring diagrams for this tractor, not the SOS

 

[kuschneider]

Installed a new starter relay, run switch, and starter bush button. Starts as it should. Appears the "Park safety" switch is not grounding. The tractor would not crank unless i run a jumper from the push button starter switch directly to ground.

I have the FO-20 manual. It has a SOS section in it, but I didn't see anything about this switch specifically. Is there another SOS manual supplement I need to track down?

 

[Soundguy]

yes, there is an sos supplement.

 

[kuschneider]

Tracked down the mother of all manuals,
The Ford Service Manual
1954-1964
With the SOS Supplement

Its about 500 pgs. Wish I'd found this one first.