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Discussion Starter · #1 ·
I converted a 66 Country Squire from an automatic to a TKO 5 speed using pedals and linkage from an original 4 speed car.
Should I override my neutral safety switch? and how do I do that?

It won’t turn over and I’m guessing that has something to do with it.
 

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For cars that were originally equipped with auto trans....
The neutral safety switch is also combined with the back-up light switch.

"Back in the day" when those cars came from the factory with a manual trans,
the neutral safety circuit was "jumpered" so you could start the engine at any time, even "in gear".
Back-up light switch was then mounted somewhere on the shifter linkage.

Find the neutral switch and unplug it, and jumper the red/blue stripe wires.
You will not have back-up lights unless you have a 2 terminal switch on the trans that makes contact in reverse only,
and you would have to run wires (black/red stripe on original harness) from the car harness to that switch.

"Modern" cars with manual trans have a clutch safety switch that basically takes the place of the auto trans neutral switch.
To really be safe you should wire a switch on the clutch pedal so that the clutch pedal must be pressed to start the engine.
This of course, prevents the engine from being started "in gear".

As an alternative to all the above....

Leave the neutral switch connected, and position it so it is "permanently" in Neutral or Park so you can start the engine at any time.
Again, you wont have back-up lights unless you cut those wires (Black/Red stripe) and wire them to a reverse switch on the trans.

Leaving the neutral switch "permanently" in N or P means it could get bumped and move out of position and then..... no start.

Also, it depends which type of switch you have...
Ford used 2 different types....
If the original switch mounted on the steering column (or floor shift console)
it is spring loaded so it would (should) move to the Park position on its own.

If your original switch was mounted on the auto transmission,
then you would have to manually turn the switch to the park or neutral position.
That switch is not spring loaded.

Very likely your car came with the spring loaded switch mounted to the steering column.
 

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Discussion Starter · #5 ·
Thanks for the quick info! My neutral safety switch was on the auto column. I might just hide a small momentary push button under the dash that would need to be pushed while turning the key. That would work for safety and anti theft.
My TKO is a pretty early one but I’m pretty sure it does have the wires for the reverse lights.
 

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For cars that were originally equipped with auto trans....
The neutral safety switch is also combined with the back-up light switch.

"Back in the day" when those cars came from the factory with a manual trans,
the neutral safety circuit was "jumpered" so you could start the engine at any time, even "in gear".
Back-up light switch was then mounted somewhere on the shifter linkage.

Find the neutral switch and unplug it, and jumper the red/blue stripe wires.
You will not have back-up lights unless you have a 2 terminal switch on the trans that makes contact in reverse only,
and you would have to run wires (black/red stripe on original harness) from the car harness to that switch.

"Modern" cars with manual trans have a clutch safety switch that basically takes the place of the auto trans neutral switch.
To really be safe you should wire a switch on the clutch pedal so that the clutch pedal must be pressed to start the engine.
This of course, prevents the engine from being started "in gear".

As an alternative to all the above....

Leave the neutral switch connected, and position it so it is "permanently" in Neutral or Park so you can start the engine at any time.
Again, you wont have back-up lights unless you cut those wires (Black/Red stripe) and wire them to a reverse switch on the trans.

Leaving the neutral switch "permanently" in N or P means it could get bumped and move out of position and then..... no start.

Also, it depends which type of switch you have...
Ford used 2 different types....
If the original switch mounted on the steering column (or floor shift console)
it is spring loaded so it would (should) move to the Park position on its own.

If your original switch was mounted on the auto transmission,
then you would have to manually turn the switch to the park or neutral position.
That switch is not spring loaded.

Very likely your car came with the spring loaded switch mounted to the steering column.
VERY GOOD ADVICE
 

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Going to be crossing this bridge soon myself with a Toploader convrsion...this is amazing info.

If I read correctly, I have to jumper my current neutral safety switch (column mount) and will have no back-up lights.

However, from Ricky's picture above, the Toploaders seem to have provisions for a reverse light switch that I can wire in. I assume it's an internal contact with the reverse gear mechanism. Do they make repros of those switches? I have an original Galaxie Toploader to use (after I rebuild it for wide ratio), but I need to go outside and see if it has the spot for that switch.

EDIT: Just found out the Toploader reverse switch is a simple lever activated unit (externally mounted and actuated). So that makes things a bit "easier".

Not having a safety switch on the clutch is okay for me, as my 1950 F1 doesn't have that, and it's second nature to jiggle the stick in neutral and stepping on the clutch before starting it. But for other drivers or whoever owns it next, this could be a concern. How would one wire in a clutch switch on these cars? Modification of a pedal-mounted brake lights switch or using a modern design somehow?

or @66CountrySquir, what might the wiring for that momentary switch look like?
 
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Hey 66 Country Squire, I just finished an auto to TKX conversion on my 65. I just jumped out the neutral safety switch for now. TKX has a neutral switch on it that I can use, but it needs to run through a relay in order to handle the amperage. My kit was from Modern Driveline and they have instructions on their website for it. Here is a picture of my "jump." Just connect the 2 red wires that are going to the plug that plugs into the column-mounted switch.
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Why is the amperage so high for the Neutral switch on the TKX? Do you not have reverse lights at this point either?

My '58 Volvo didn't come with back up lights, but it was a bumper-mounted option, lol!! I put on an old VW backup light but my original trans didn't have a switch on it. I wound up rigging a toggle switch on the dash for the reverse light for inspection purposes, but I always forgot to use it. And it didn't do much for visibility anyway.

I'd rather not go that route with my Galaxie.

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Ha! nice workaround.
The TKX came with a harness to wire the reverse lights, I just haven't gotten there yet.
I questioned the amperage on the neutral switch as well, Modern Driveline said the wires on the TKX switch itself are meant for a low amperage signal only and the factory neutral switch circuit is too high and long term would melt the wires. below is the neutral harness that comes on the TKX:
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Looks like a great install!

And that is definitely a modern wiring harness, for sure, and likely plugged into some sort of voltage reducers or relays to minimize the load on switch. Are those wires pretty straightforward from that switch (ie: remove the plug and splice them into the existing reverse light wiring (after the relay)?

Thanks for the pic!
 

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Not having a safety switch on the clutch is okay for me, as my 1950 F1 doesn't have that, and it's second nature to jiggle the stick in neutral and stepping on the clutch before starting it. But for other drivers or whoever owns it next, this could be a concern. How would one wire in a clutch switch on these cars? Modification of a pedal-mounted brake lights switch or using a modern design somehow?

or @66CountrySquir, what might the wiring for that momentary switch look like?
Agree with @Dakar09 that the clutch switch is not necessary. In fact, manual shift vehicles load the crank thrust bearing every time you push in the clutch and a safety switch on the clutch requires loading the thrust bearing prior to building oil pressure. I jumpered the clutch switches on several of my cars and just made sure I was in neutral before cranking - just like Dad taught me in the 1958 Courier. :geek:
 

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Discussion Starter · #13 ·
I just found out that my old TKO has a built in neutral safety switch also but I didn’t know that voltage would be too high. I was just going to wire it straight to the factory wires. I better call Modern Driveline next week.
 

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Discussion Starter · #14 ·
and wait a minute… if jumping those two wires together is fine why couldn’t I just run it to the trans wires? The transmission doesn’t add voltage, it’s also just closing the circuit.
Am I thinking about this wrong?
 

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Yes, the switch just closes the circuit, same as the auto trans neutral safety switch.

The current (amperage, not voltage) those wires carry is only what it takes to energize the starter solenoid.
Probably about 1 or 2 amps, and only for the time that the starter cranks the engine.

IOW, very low current for a short amount of time, so the switch should be fine to handle that current/amperage.

Current is the flow of electricity, and amperage is the unit to measure current.
The two words sometimes get used interchangeably.

Voltage in most automotive circuits in these old cars, is "more or less" 12 to 15 volts and remains "more or less" relatively constant.
There are exceptions, but we don't need to worry about that here.

Amperage is the concern.
Any given circuit must have correctly sized wire and fuse, and properly rated components (switches as an example) for the amperage the circuit is designed for.
Too small a wire (or a switch rated for 1 amp) in a circuit that say, draws 10 amps, and the wire (or switch) will overheat and potentially cause a fire.
Wire length comes into play as well.
A very long wire carrying high amperage will need to be thicker than a short wire at the same amps.
There are wire length and gauge charts online (Google search) to help choose proper wire gauge for a given amount of current/amperage.
You would need to know the current draw of any given circuit and how long the wires are to hook it all up.
From there you find the gauge of wire that will safely carry that current for that length of wire.

Modern cars with computers and such, have other voltage requirements, in addition to the "normal" 12 volt systems.

That neutral switch on the TKO might be intended for a modern car where the engine cranking is controlled by the computer.
In that case, that switch would just be a "signal" to the computer, probably 5 volts and very low (micro) amps, so the computer knows it's ok to crank the engine.
It's still possible the switch does have a high enough amp rating to carry the start solenoid energize current for an old car.
At best the switch works for a while and then burns out and no engine crank for you.
At worst the switch overheats, causes a fire, and burns down your car.
 

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Discussion Starter · #16 ·
So much longer wires plus looping through the transmission will draw more power?
Will heavier wires to and from the trans fix this or should I go back to my plan of calling Modern Driveline?
 

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So much longer wires plus looping through the transmission will draw more power?
Will heavier wires to and from the trans fix this or should I go back to my plan of calling Modern Driveline?
The safe thing to do....
Call them to see if that switch will handle the start circuit current on your car.

If the switch will handle the current...
The added length of wire should be minimal and not a big concern.
Use the same gauge of wire that the existing circuit uses.
If worried about it, go up one wire gauge size.

If the switch will not handle the current, you could wire in a relay.
The switch would then energize the relay, which in turn would energize the starter solenoid.
 
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