What Master Cylinder are you planning on running?

 

Its a parts store replacement 95 YJ one and matching booster.

 

fully relaxed there should be ~ 1/32 space. if there is no space the pressure will not release and the brakes will eventually stay locked. too much and of course too much travel. it's a pretty hair trigger adjustment. when you get it close a half turn is a lot.

 

I have never used this tool but I thought I would throw it out there.
https://www.amazon.com/Power-Brake-Booster-Adjustment-Tool/dp/B079QGXY55
I did mine on a driveway that had a slight incline.
Tighten it up until the Jeep will not move, then loosen it until it does move.
No more than 1/2 turn each time.

 

I've taken the master off and taken 6 turns out of the rod and put it back on with little improvement. hoping someone would be able to say "yup - mine has 13 threads showing on the rod". Something to get me in the ballpark.

 

turn it out a bunch until you can tell it's contacting the piston and how far the master is from seating

99% of the time you don't need to mess with this. Is it a reman?

 

It is a reman and I've never had to mess with it when I've done them in the past. But tye one I got had the nut all the way turned in with no threads showing. When I search the forums I see a lot of posts about a batch of these being like this and everyone had a 50/50 shot of them needing to be adjusted.

 

Just for grins could you show us a picture of the Master Cylinder?
Especially where it goes into the Booster.

 

Like this?