727 valve body--Is This a Trick---With this Stick? (of 1/4" keystock)

[hofferwood]

My first trans re-do valve body too-----yada yada.
Does this stick of 1/4" key do anything, other than not allow this shuttle valve to move at all?
The only other thing I can see done to this, was the accumulator spring was left out.
I am putting a Transgo TF-1 in it also.
Shoud I leave it in, or just put it back the way it was supposed to be (with the spring and able to move)?
It goes in the top hole.









Thanks, Chuck.

 

[pnora]

You should take the number off that valve body and find out what year it is. Then get the FSM and see what it was assembled with. My bets that key is from some sort of modification or shift kit. There can be other mods done which can include drilling and who knows what all. What sucks is one mistake and you have operation issues.

 

[turbine68rt]

From what I'm seeing the shuttle valve rod is used to firm up shifts. If you're only using the TF-1 kit and there are no other prior modifications done compared to your included instructions, I would remove the rod and reinstall it the way it originally was. Check casting date on the valve body and compare to other components and the case to verify whether it is consistent or was assembled using different cores.

 

[oldkimmer]

It’s an old trick from back in the day. There is probably 1 of the 1/4 inch balls removed also. I think they called it the No Buck shift kit. I think they also turned up the line pressure a couple of turns. I have in a magazine somewhere but have no idea which one. Kim

 

[Dave6T4]

I have done a lot of transmissions, and have never seen this. Not even on shift kit instructions. I often left the accumulator spring out of builds. Even the factory left it out of certain transmissions. Some shift kits called for installing a blocker rod under the accumulator, but I found that this made part throttle shifts very harsh.

 

[oldkimmer]

Some B&M shift improver kids block the shuttle valve. They also have a different separator plate to install. Kim

 

[hofferwood]

It’s an old trick from back in the day. There is probably 1 of the 1/4 inch balls removed also. I think they called it the No Buck shift kit. I think they also turned up the line pressure a couple of turns. I have in a magazine somewhere but have no idea which one. Kim

I think this is the one @oldkimmer , because there was a check ball missing,------and you'll never believe where I found it-----inside the spring of the 2-3 shift valve.(rigt under the keystock in the pic).



It either bounced in there, or he put there for safe keeping. I saw it as I was slowly pulling the cover off. I dunno.

I put it back where it went (the screw is pointing to it).



Now it's all back together with the TF-1 kit installed.
I should get the trans back in this weekend.

I'd like to thank everyone that responded!!

Thanks again
Chuck

 

[Dave6T4]

You likely should have left that ball out. Some of the wall of a neighbouring channel has been milled out, a sure sign of a previous shift kit modification.

 

[hofferwood]

You likely should have left that ball out. Some of the wall of a neighbouring channel has been milled out, a sure sign of a previous shift kit modification.

Thanks Dave6T4, I milled that out and put the ball back per the TF-1 instructions.
So I guess we'll se what happens when we get her put back in.