neutral safety switch

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edbux

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I guess this is the right forum. 67 Dart converted from S6/904 to 360/727.
The trans originially had a 2 prong switch. Then the shifter selector shaft starting leaking. Due to work demand, I took it in for repair. While under there, the mechanic said the safety switch was leaking and replaced it. The PO never had the switch connected nor is the plug anywhere to be found. The starter relay conncection for the switch is ground to the battery, allowing it to start in gear. I want to connect the 3 prong switch, where will the wires connect?
My factory manual shows the 2 prong. Anyone have a schematic or words of
advice that will help?

Thanks
 
haynes offers no help but i looked for you!..

i now know what a three prong looks like, but it tells you only how to test it and how to replace it, but im sure we all already knew how to unscrew one.

sorry man, im sure someone will help.. theres a lot of us changing from 904 to 727..


Cerwin
 
Center prong is the nuetral saftey switch. Outside 2 are for the reverse lights.
 
I don't think there's a two-prong switch, only single (nuetral safety only) and three prong (NSS and backup lights). If you don't have the one that matches the comb in the transmission it won't work (or so I've been told - never tried it).
 
Jim is correct in all cases. I've been doing trans. work on torqueflites since 1981 and never seen a 2 prong switch on a 727. Only the single prong was used through either 68 or 69 then they switched to the 3 prong unit. The Correct one does have to be used also to match the rooster comb of the shifter mechanism so hopefully he put the right one in. If not it may not engage properly. Adam is also correct about the wiring. just run a wire from the center pin to your relay and that's all that's needed. The single prong connector is only available from resto shops nowadays and it's very expensive (usually like $75-80) so I use the 3 prong unit and do what I mentioned above.

Boy it's amazing that shop did that to your car. Sounds like their some boneheads that haven't heard the word liability. If you talk to them again you might ask them what they'd think could happen if someone started it in gear and someone was in front of the car. Can we say lawsuit time!!!
 
Thanks to all for the info. Actually the shop matched the 3 prong that was already in there. The previous owner used the engine and trans from
a 74 truck, as far as I can tell, when swapping from a S6. The neutral safety feature has never worked and I will correct it. I'll buy the correct switch and use the 3 prong plug as suggested. Again, thanks!
 
On the older cars the reverse switch was on the gear shift - either on the column or on the floor shifter itself. To change over to the later style you need to locate the wiring for the shifter operated switch and wire it to the lead on the three prong tranny switch. A wiring diagram would help you a lot needless to say -

I did this on my 66 since the shifter switches on my stuff were all junk anyway. A later model trans wiring harness will make this a slick install as well.

Evans wiring harnesses made me up a nice new three prong harness to work with this stuff.
 
Does the 3-prong NSS work the same with a 727 with a reverse manual valve body? I was wondering if it would turn the reverse lights on when it is in 2nd gear instead of reverse. I assume they work the same, but thought I would double-check.

Thanks in Advance,
Brian
 
Brian, no, the neutral safety works the same in a reverse pattern valvebody. You are only changing the forward speeds in the pattern not the whole pattern. P R N are in the same location in the pattern regardless of the forward speeds pattern. Also if you think about it 2nd gear stays in the same spot only 1st and 3rd (D) get swapped.

P R N D 2 1 standard

P R N 1 2 D reverse

Chuck
 
Jim Lusk said:
I don't think there's a two-prong switch, only single (nuetral safety only) and three prong (NSS and backup lights). If you don't have the one that matches the comb in the transmission it won't work (or so I've been told - never tried it).
Click to expand...
I'd like to jump in here. I am having nss issues. I understand it is just a ground to make the circuit complete. My question is you said above if you do not use the one that matches the comb in transmission it will not work or so you have been told. Are there more than one 3 prong nss? I think the next thing I need to do is check the adjustment on the shifter. It starts intermittent I get it to start but after awhile (take a trip down the road it may or may not start. Don't you just love auto electrical issues anyway after new wire from relay to nss then a new nss switch. I think maybe try adjusting shifter cable. I can jump the relay all day long again it may or may not start with the key. Now with that said and I sure you have heard this alot it was working then all of a sudden. Well what do you think
 
The "newer stuff" has a different connector, but I have no idea if the actuation end is different or not
 
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