904 NSS and rooster comb question

[4spdragtop]

I went to swap NSS switches and rooster comb. 3 wire NSS in a LU 904 coming out and 1 wire going in. I read that rooster combs are different and ya gotta match them. Well I cant without grinding off the "tang" off my 67 non LU 904.
There's a section of "whatever" that gets in the way when shifting thru gears with the mate to 1 wire NSS (67). Can I just grind the tang down off the comb?(Last Pic with pointer)
Thanks
Steve

 

[4spdragtop]

This difference as well.

 

[RustyRatRod]

I don't know the answer to your question, Steve, but you have two completely different valve bodies there. One is early without the part throttle kickdown and the other is a later one with it. in your very first picture, the valve body you have your pinky on has the part throttle kickdown, the other does not. I don't know if that's any help or not, but I would try to use the one with the part throttle kickdown.

 

[fshd4it]

Just use the later 3 wire NSS, but don't hook up the 2 wires for the reverse lights? All you'd need is the 3-prong plug.

 

[Dana67Dart]

@Oldmanmopar posted a post showing the 3 904 combs

 

[4spdragtop]

Thanks Rob, yes the one on left/pinky in 1st pic is from LU 904, the trans. That part throttle kickdown is significantly larger than what's in the orig 904. That's why rooster is smaller in LU to compensate for the PT kickdown. Not sure if that tab engages with anything or not. May have to mock up somehow and see.

I don't know the answer to your question, Steve, but you have two completely different valve bodies there. One is early without the part throttle kickdown and the other is a later one with it. in your very first picture, the valve body you have your pinky on has the part throttle kickdown, the other does not. I don't know if that's any help or not, but I would try to use the one with the part throttle kickdown.

 

[Vaanth]

I went to swap NSS switches and rooster comb. 3 wire NSS in a LU 904 coming out and 1 wire going in. I read that rooster combs are different and ya gotta match them. Well I cant without grinding off the "tang" off my 67 non LU 904.
There's a section of "whatever" that gets in the way when shifting thru gears with the mate to 1 wire NSS (67). Can I just grind the tang down off the comb?(Last Pic with pointer)
Thanks
Steve

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View attachment 1716498512

If using the early, 1966 - 1968 selector (rooster comb) in the 1978 and later lockup valve body, the tang can be ground down to clear, but the stop will not align properly as the profile of the tang in that area differs. Note the spacing in the area where the parking rod engages in the following image:

It will work, but over travel can occur at the end of the selector range. With careful rods/shifter alignment, adjustment, good bushings or rod/hole fit, and awareness of the issue, it should be okay.

As mentioned in the prior post #4, the simplest, and safest, approach is to keep the later selector and neutral safety switch and wire in the matching connector. The center terminal is the neutral safety switch. The outer terminals are for the reverse lights, which won't be connected, unless desired to re-route your 1967 wring.

Note that the neutral safety switch connector shape differs between the 1969 - 1976 unit and the 1977 and later unit. The early connector, Chrysler part number 2926502 (includes pigtail), will not fit the later switch well. The later connector, Chrysler part number 4209695 (includes pigtail), will fit either.

Standard Motor Products part number S-747 or Wells number 645 is a replacement for 4209695. You likely know because you have the later valve body already, but the connector and pigtail looks like the following image:

 

[4spdragtop]

Thanks for all that info! So if I use 3 wire NSS I just have to leave the 2 outer wires disconnected? Im not against doing that.

If using the early, 1966 - 1968 selector (rooster comb) in the 1978 and later lockup valve body, the tang can be ground down to clear, but the stop will not align properly as the profile of the tang in that area differs. Note the spacing in the area where the parking rod engages in the following image:
View attachment 1716498534

It will work, but over travel can occur at the end of the selector range. With careful rods/shifter alignment, adjustment, good bushings or rod/hole fit, and awareness of the issue, it should be okay.

As mentioned in the prior post #4, the simplest, and safest, approach is to keep the later selector and neutral safety switch and wire in the matching connector. The center terminal is the neutral safety switch. The outer terminals are for the reverse lights, which won't be connected, unless desired to re-route your 1967 wring.

Note that the neutral safety switch connector shape differs between the 1969 - 1976 unit and the 1977 and later unit. The early connector, Chrysler part number 2926502 (includes pigtail), will not fit the later switch well. The later connector, Chrysler part number 4209695 (includes pigtail), will fit either.

Standard Motor Products part number S-747 or Wells number 645 is a replacement for 4209695. You likely know because you have the later valve body already, but the connector and pigtail looks like the following image:
View attachment 1716498533

 

[Vaanth]

Thanks for all that info! So if I use 3 wire NSS I just have to leave the 2 outer wires disconnected? Im not against doing that.

Yes, leave them disconnected.

You could cut them off flush for a neater installation, but I'd tuck them out of the way, or maybe heat shrink them to the center wire before splicing it in, just in case I ever want to use the later switch and reverse light setup.

 

[4spdragtop]

Thanks, that definitely helps. I'll make sure to leave enough wire for future hookup if need be.
A torque converter question....the LU converter I plan on using is unknown as is 904. Can I use a boroscope to get inside torque converter? To chk for damage?

Yes, leave them disconnected.

You could cut them off flush for a neater installation, but I'd tuck them out of the way, or maybe heat shrink them to the center wire before splicing it in, just in case I ever want to use the later switch and reverse light setup.

 

[Vaanth]

Thanks, that definitely helps. I'll make sure to leave enough wire for future hookup if need be.
A torque converter question....the LU converter I plan on using is unknown as is 904. Can I use a boroscope to get inside torque converter? To chk for damage?

It's worth a shot to try the borescope, but I'm not sure how much you could see beyond the center into the outer areas. There are many turbine, impeller, and stator fins and vanes that might not be too accessible. The lock-up clutch friction surface might be glimpsed near the center for a clue, but I've never looked myself.

Lock-up converters don't have a drain plug, so you can't fully drain one, but the remaining fluid might show something about its health.

 

[4spdragtop]

Wow, SMP is proud of their pigtail...$55 Cdn Standard Motor Products S747 Pigtail/Socket, Pigtails & Sockets - Amazon Canada

 

[Vaanth]

Wow, SMP is proud of their pigtail...$55 Cdn Standard Motor Products S747 Pigtail/Socket, Pigtails & Sockets - Amazon Canada

If you can find an Auveco distributor in Canada, look for number 23155. US pricing is about $20.

The last couple that I bought, were from a local Chrysler dealer, number 4209695, for about $3 each, but that was 30 years ago. A junkyard is a possibility for one, but the wiring can be brittle.

Some other possibilities:

AC Delco: PT2139
Car-Pak: 98-7891
Carquest: PTA1148
GM: 88861067, 42096502

 

[RustyRatRod]

Thanks Rob, yes the one on left/pinky in 1st pic is from LU 904, the trans. That part throttle kickdown is significantly larger than what's in the orig 904. That's why rooster is smaller in LU to compensate for the PT kickdown. Not sure if that tab engages with anything or not. May have to mock up somehow and see.

I apologize for basically a non answer, but I wanted to make sure you knew the difference and knew you had the part throttle kickdown if you wanted to use it.

 

[4spdragtop]

Its all good, this is my 1st time tearing into a transmission this deep. Any info is good info. I thought at first you meant the bigger plate with 6 screws on LU(1st pic) but then realized you meant the side "piece"(2nd pic).
Ordered a selector shaft seal and then button it up.

I apologize for basically a non answer, but I wanted to make sure you knew the difference and knew you had the part throttle kickdown if you wanted to use it.

 

[RustyRatRod]

Its all good, this is my 1st time tearing into a transmission this deep. Any info is good info. I thought at first you meant the bigger plate with 6 screws on LU(1st pic) but then realized you meant the side "piece"(2nd pic).
Ordered a selector shaft seal and then button it up.


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Correct. That's called the part throttle valve body. It's a nice addition. Makes it downshift without having to bend the floor with the gas pedal. lol