Auto transmission safety switch 57 Ford

[Habusailor]

Does anyone have a wiring diagram for the safety switch and or the ignition switch?

Also instructions as how to adjust the safety switch. I understand the 57 was set up to only start in neutral. Mine starts in all gears now so needs to be adjusted and I am not sure it is wired correctly. The car is a recent purchase.

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[dmsfrr]

Here's a wiring diagram for the starting circuit. Power to the NSS comes from the Start terminal of the ignition key switch.
Allowing the car to start in Park as well as Neutral may have begun in '58 or maybe '59? The new replacement neutral safety switches work that way too.
Don't be surprised if the NSS has been bypassed somewhere in its wiring.
In a column shift car the NSS is on the steering column (not sure exactly where, I don't have one)
.

[Habusailor]

Thanks for the info. On the column shift cars the safety switch is located on the steering column under the hood, close to the firewall where the shift linkage is. Mine is mounted correctly, has 4 wires coming off it, which is correct, I hadn't had time to trace where the wires go, and need to see if my ignition switch is wired properly. Just bought the car, lots of these little things to figure out and correct.

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[Ford blue blood]

One pair is for the safety switch the other is for the back-up lights.

[Merc Cruzer]

Not sure if this will help. This is on a 53' Merc with an Merc-O-Matic. When I bought it, it would start in any position. The first picture shows it originally. The rest are after I rewired it.

[54vicky]

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if you look on the left front fender the wiring harness should have the switch wires exiting and the switch wires plug into them.the wires do not run directly to the switch but they are run from the harness via short plug in wires.one pair are bullet the other pair will be spade at switch.without looking I can not remember which is which but a test light will help.

[Merc Cruzer]

On mine the (spade) wires are green and the back up lights (bullet) are the brown and red wires. The green wires control the starter lock out for neutral.

[Daves55Sedan]

If the ignition switch cranks the starter no matter what gear the select lever is in, then a previous owner has bypassed the starter neutral switch by disconnecting the two red wires from the bullet connectors on the switch, and connecting the two red wires together. This is exactly the way the cars with standard transmissions are wired. Fomoco used the same wire harness, but on manual transmission cars the two red wires were not needed, so they just hooked them together with a rubber-coated bullet connector.
Those two red wires are just an enable signal to complete the start circuit.
It is possible that the contacts in the switch burned out, OR, he couldn't get the switch adjusted right to get contact when the gearshift lever is in neutral, so he disconnected the enable wires together to bypass the switch.

[Daves55Sedan]

BTW, the repro starter neutral switches (now costing an arm and a leg) aren't worth a hoot. The contacts inside the switch are substandard and mounting method on the arm is pitiful. Cheap Chinese made junk, but looks like the original on the outside.
Not much you can do but get a new one and hope it lasts a couple years.