Potential 727 Transmission Selector Shaft Seal Issue - 1962 Vintage

[Charlie Brown]

Doing a re-seal on my 62 big block 727. First time doing this, so I'm green in this area. I have 2 seals which look similar in my re-seal kit, but are of different outside dimaters.

The I.D. of the valve body bore for this seal -

The larger seal fits the bore snug, but it does not allow the rooster comb to seat all the way down.

The smaller one fits the bore a bit loose but allows the rooster comb to rest at the correct height.

When I put the rooster comb on the shaft I have to push it down to clear the slot for the c-clip. I'm wondering if when I do this, the seal will expand to take up the .1 difference in bore diameter. It looks like the first seal is the correct one to use, but I can't get the rooster comb to seat properly. Any yes, I've put that seal in both ways. As an aside, when I took the valve body out, there was NO seal on the shaft. Either I'm missing something or someone forgot to install one.

 

[Sixpaksteve]

Doug, @dvw here on B bodies, knows these transmissions inside and out and I believe that he can help you out.

 

[threewood]

Does a gasket even go on the valve body there? That looks like the seal that goes in the case under the shift/throttle arms.

 

[493 Mike]

The larger seal fits in the top recess of the rooster comb with a flat washer on top of it followed by a snap ring. The smaller fits in the speedometer pinion adapter (outside with cable threads) followed by the friction fit snap ring. Lips face in.
Mike

 

[Charlie Brown]

Does a gasket even go on the valve body there? That looks like the seal that goes in the case under the shift/throttle arms.

Good question. I'm assuming that because the selector shaft penetrates the case that there should be some kind of seal on the shaft.

 

[493 Mike]

Does a gasket even go on the valve body there? That looks like the seal that goes in the case under the shift/throttle arms.

The case seal is a metal/rubber that presses in the case to seal the OD of the rooster comb shaft. I have found they install easily with a 1/2 nut/cap screw and flat washers on each side. Don't torque the assembly too much with your 1/2" wrenches!
Mike

 

[Charlie Brown]

The larger seal fits in the top recess of the rooster comb with a flat washer on top of it followed by a snap ring. The smaller fits in the speedometer pinion adapter (outside with cable threads) followed by the friction fit snap ring. Lips face in.
Mike

Oh boy - I missed that one. Trans is upside down on a stand and I didn't see this external seal. Thanks for this. Great site we have here.

 

[Sixpaksteve]

Great site we have here.

Agree! And I'm enjoying learning something new today. Thanks to all who have responded so far!

 

[dvw]

The case seal is a metal/rubber that presses in the case to seal the OD of the rooster comb shaft. I have found they install easily with a 1/2 nut/cap screw and flat washers on each side. Don't torque the assembly too much with your 1/2" wrenches!
Mike

The metal clad seal is used in the 66 and up non cable shift trans to seal the shift selector shaft (rooster comb assy). The case seal on 62-65 is the larger of the 2 seals pictured in post #1. It seals the throttle pressure shaft to the case. This same seal is also used in 66 and newer valve bodies to seal between the throttle pressure shaft and the shift selector shaft. The 62-65 trans doesnt have a shift selector seal because the shift selector is the front cable,
Doug

 

[R/T Boy 67]

Would you mind posting the numbers, and letters if any, that are stamped into the trans just above the pan rail on the driver's side. I'm interested in the numbers on the real early 727s.

 

[Charlie Brown]

Would you mind posting the numbers, and letters if any, that are stamped into the trans just above the pan rail on the driver's side. I'm interested in the numbers on the real early 727s.

It's your lucky day. I just took this photo yesterday - just in case for future reference. I hope the trans works as good as it looks!

 

[R/T Boy 67]

Yes, it does look nice. Thanks for the photos.