1 pin NSS to 3 pin wiring?

Isaiah Estrada

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My 68 New Yorker had no transmission when I bought it. It wasn't too hard to find another 727, and coincidentally - it was built in '67 (as per the casting numbers on it.) At some point though, someone put a 3 pin NSS on it. I had the transmission rebuilt over a year ago before I had any idea of what the NSS really was. Now looking back, I wish I could've had them change it back.

Since it's got the 3 pin setup now, I can only assume it has the right rooster comb inside of it to properly engage the reverse lights and actually function as it should. How can I update my 1 pin wiring to accept the 3 pin? Wiring is my weak point and something I am still trying to learn about. I appreciate any help I can get on this.

1662406627737.png


1662406658569.png


Casting numbers: PK2801541J 2320 5696 W S
2801261 - 7 KCP
 

thethee

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I may be wrong here but I'd think you'd best hook up your trans as if it was a 1 pin NSS instead of trying to adjust your wiring. As long as you connect your current 1 wire to the centre pin of that NSS everything will work as it should. Your current reverse light switch should be at the base of the column and should work regardless of what NSS is equipped. Hopefully someone can confirm
 

65sporty

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I may be wrong here but I'd think you'd best hook up your trans as if it was a 1 pin NSS instead of trying to adjust your wiring. As long as you connect your current 1 wire to the centre pin of that NSS everything will work as it should. Your current reverse light switch should be at the base of the column and should work regardless of what NSS is equipped. Hopefully someone can confirm
I believe you are correct, center pin NSS, outer pins are back up lights.
 

1970FuryConv

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On my 1970 Fury
NSS
Center terminal to starter relay ground, lower left term on relay. Brown/Yellow wire

Reverse Lights: 2 remaining wires go to terminals #2 & #6, upper right 2 wire connector at bulkhead connector behind fusebox. FSM 8-135

If your reverse lights turn on with movement of the shift lever, outside terminals of 3-wire Neutral Safety Switch are irrelevant on your car
 

MetalManiacAZ

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The trans on my 68 Imperial is from a '74. I installed a 1 pin NSS, hooked up the ring terminal, and it works just as it should. When I bought the car, the PO (flipper) was jumping the relay with a screwdriver because he didn't know what was wrong with it!
 

Big_John

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My 68 New Yorker had no transmission when I bought it. It wasn't too hard to find another 727, and coincidentally - it was built in '67 (as per the casting numbers on it.) At some point though, someone put a 3 pin NSS on it. I had the transmission rebuilt over a year ago before I had any idea of what the NSS really was. Now looking back, I wish I could've had them change it back.

Since it's got the 3 pin setup now, I can only assume it has the right rooster comb inside of it to properly engage the reverse lights and actually function as it should. How can I update my 1 pin wiring to accept the 3 pin? Wiring is my weak point and something I am still trying to learn about. I appreciate any help I can get on this.

View attachment 556318

View attachment 556319

Casting numbers: PK2801541J 2320 5696 W S
2801261 - 7 KCP
The easiest way to figure out what you have is just drop the pan and take a look.

The rooster comb you want for a '68 "single pin" NSS is in the center. You'll see it. The one on the right is for the 3 pin NSS.

1662422461879.png
 

Big_John

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So you know what it looks like mounted. This is looking down on the valve body, but you can see the rooster comb sticking out the right side. This one is for a '69 and up trans.

1662422612822.png
 

MrMoparCHP

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Put it in Park, should have continuity between pin 1 & 3, pin 2 should be open to ground.
Put it in Reverse, should have continuity between pin 2 & the transmission housing, continuity between pin 1 & 3 should be open.

If these do not work it might just be the wrong switch.


Alan
 

Isaiah Estrada

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The easiest way to figure out what you have is just drop the pan and take a look.

The rooster comb you want for a '68 "single pin" NSS is in the center. You'll see it. The one on the right is for the 3 pin NSS.

View attachment 556375

So you know what it looks like mounted. This is looking down on the valve body, but you can see the rooster comb sticking out the right side. This one is for a '69 and up trans.

View attachment 556378

Or!!

Pull the NSS and look in the hole. That's even easier.

Thanks for the tips! I will pull the NSS and have a look. I have trans outside of car so it's easiest for me to do this now.
 

Isaiah Estrada

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I may be wrong here but I'd think you'd best hook up your trans as if it was a 1 pin NSS instead of trying to adjust your wiring. As long as you connect your current 1 wire to the centre pin of that NSS everything will work as it should. Your current reverse light switch should be at the base of the column and should work regardless of what NSS is equipped. Hopefully someone can confirm

I believe you are correct, center pin NSS, outer pins are back up lights.

On my 1970 Fury
NSS
Center terminal to starter relay ground, lower left term on relay. Brown/Yellow wire

Reverse Lights: 2 remaining wires go to terminals #2 & #6, upper right 2 wire connector at bulkhead connector behind fusebox. FSM 8-135

If your reverse lights turn on with movement of the shift lever, outside terminals of 3-wire Neutral Safety Switch are irrelevant on your car

The trans on my 68 Imperial is from a '74. I installed a 1 pin NSS, hooked up the ring terminal, and it works just as it should. When I bought the car, the PO (flipper) was jumping the relay with a screwdriver because he didn't know what was wrong with it!

Thank you fellas!
 

Isaiah Estrada

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Put it in Park, should have continuity between pin 1 & 3, pin 2 should be open to ground.
Put it in Reverse, should have continuity between pin 2 & the transmission housing, continuity between pin 1 & 3 should be open.

If these do not work it might just be the wrong switch.


Alan

Very helpful, thanks for the tips!
 
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