Just checking - which neutral safety switch for my 1962 transmission?

[David Womby]

My 64 Bristol 408 has a 1962 727 push-button transmission. It starts just fine in reverse or drive - ask me how I know!

I haven't crawled around to see if it's just a loose wire on the neutral safety switch, or what, yet but I have managed to get confused over whether it should have a single wire connector or or 3. The notes I have from the previous owner say the transmission serial is 2400157 022398. I am thinking it will be the single connector one. Is anybody able to confirm and provide the part number, please?

David
1964 Bristol 408 - Chrysler 360 engine / 727 push-button transmission.

 

[493 Mike]

My 64 Bristol 408 has a 1962 727 push-button transmission. It starts just fine in reverse or drive - ask me how I know!

I haven't crawled around to see if it's just a loose wire on the neutral safety switch, or what, yet but I have managed to get confused over whether it should have a single wire connector or or 3. The notes I have from the previous owner say the transmission serial is 2400157 022398. I am thinking it will be the single connector one. Is anybody able to confirm and provide the part number, please?

David
1964 Bristol 408 - Chrysler 360 engine / 727 push-button transmission.

A 62 should have the single threaded stud but I can't tell you the PN.
Mike

 

[snakeoil24]

3 wire started in late 67 to 68 i believe

 

[1 Wild R/T]

NOS 1955-64 Plymouth Chrysler Dodge Desoto Neutral Safety Starter Switch 1704283 | eBay

NOS 1955-64 Plymouth Chrysler Dodge Desoto Automatic Transmission Neutral Safety Starter Switch Mopar 1704283 - 58024 370. This fits seamlessly into an automatic transmission of many 1955-64 Plymouth, Chrysler, Dodge, and Desoto vehicles.

www.ebay.com

Loose wire would be a no start.. The wire gets grounded to complete the circuit... The circuit receives 12v front the ignition switch when it the start position.. That 12v energizes the coil of the starter relay... The NSS provides the ground path for the relay coil... When the coil has ground and power it closes the relay contacts connecting the battery to the starter... Sounds like either your NSS is internally shorted or the wire from the NSS to the relay is shorted to ground....

 

[David Womby]

http://[URL]https://www.ebay.com/it...EMzAvj97YAo7CpIBTglWVBJSo=|tkp:Bk9SR5rrqJfAYw

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Loose wire would be a no start.. The wire gets grounded to complete the circuit... The circuit receives 12v front the ignition switch when it the start position.. That 12v energizes the coil of the starter relay... The NSS provides the ground path for the relay coil... When the coil has ground and power it closes the relay contacts connecting the battery to the starter... Sounds like either your NSS is internally shorted or the wire from the NSS to the relay is shorted to ground....

Thanks for the explanation. I'll try tracking down what's wrong this week.

David

 

[Dave6T4]

It sounds more like cable adjustment, or an even bigger problem. Is your '62 transmission still shifted with pushbuttons, or is it shifted with a console lever? Chrysler first offered the console lever shift in 1964 Polara 500 and Sport Fury, and carried it over into 1965 Coronet 500 and Satellite. The console shift Torqueflights required a different valve body than the pushbutton ones. Basically, there was a different manual valve and rooster comb between them. My guess is that you have a pushbutton transmission, and are trying to shift it with a central console lever. If this is the case, it will not work. You need to find a 1965-only valve body. Chrysler no longer used pushbuttons in 1965, using a single lever instead, whether console or column shifted. All 1965 valve bodies are like the 1964 console-shifted ones.
I ran into this problem last year. A friend was converting a former slant six 1964 Plymouth Belvedere to a 440, automatic, keeping the original pushbuttons. His problems sounded like yours. After dropping the pan, I discovered that his transmission had the console-shifted valve body on it. I had the parts required to convert it back to push button use, so that is what I did. After properly adjusting the cables, it worked fine.

 

[David Womby]

Thanks but it's a 62 pushbutton transmission still using pushbuttons. Might it still be a cable problem? the car doesn't creep when 'Neutral' is selected which I would have thought would indicate an issue with the cable set up but please correct me if I am wrong.

My only problem is it will start in Reverse or Drive. Am I right in thinking the Neutral Safety Switch (NSS) is physically pushed open and closed by the fingers on the lever in the valve body - so that the cable being slightly off might mean it's not in quite the right spot to disconnect the NSS even though it has selected neutral in the transmission?

David

 

[Dave6T4]

In that case, I think you have a cable adjustment problem. I have a cable-shifted Torqueflight in my 1964 Polara. I have the service manual for this car and it has a section on cable adjustment in it. You could pull your pan off, and with pushbutton in neutral, turn the cable adjustment wheel until the tang on the rooster comb is contacting the neutral start switch.

 

[1 Wild R/T]

The factory manual actually has a procedure that doesn't require removing the pan... But it requires the NSS to be working...
You hook a ohm meter up to the NSS and ground... Remove the bolt that attaches the cable adjuster wheel to the trans case...
Trans in park or neutral... (On a early car it's the exact same place) Now back the adjuster wheel off (Counterclockwise) a couple turns... Watch the meter while pushing inward on the cable and start screwing the adjuster wheel clockwise till the meter shows continuity... From there continue turning but count the bolt holes that pass till the meter shows a loss on continuity... Split the number of bolt holes in half, back the adjuster off that amount & bolt it down... Your done...

 

[QuickBpBp]

If it is the NSS make sure you buy the correct one as there are 2 different single wire ones.

 

[David Womby]

If it is the NSS make sure you buy the correct one as there are 2 different single wire ones.

Oh great. So maybe the problem is that the one put in by the PO is wrong? How would one know which to get?

David

 

[dvw]

The difference in the single pin switch's. Plastic plunger fits 65 and up and 64 console shift. Steel plunger fits 62-64 they set in the case at different depths.
Doug

 

[David Womby]

The difference in the single pin switch's. Plastic plunger fits 65 and up and 64 console shift. Steel plunger fits 62-64 they set in the case at different depths.
Doug

Thank you!!!

 

[David Womby]

It turns out my problem was not anything to do with the operation of the safety switch in the transmission. It was working fine and only grounded in neutral as intended.

In my case, it was that a previous owner had replaced the starter relay with a non-standard one and mis-wired it so that the relay was permanently grounded - thus the car would start regardless of the gear selector position.

The Neutral Safety Switch had been left out of the circuit. I have fixed it now.

David