Where does the wax string go? I rebuilt a couple 101s (circle pellet branded) but never noticed the wax string.
Never hurts, when I adjusted mine I made sure to feel the rod assembly just touch the head of the compression tube, which leaves the pump arm on the very end up about 1.5 inches from the compression tube, this also creates a slight, not hard cam over that also helps hold the pump arm up even after firing.I ask about the spring which is much like you describe, my early 101 had the same spring as yours and I found that it was to light to hold a seal on the exhaust valve closed when I did 5 or more pumps. To detect the issue I held my ear next to the receiver and I could hear very slow bubbles not a hiss at 5 pumps but adding a 6th it hissed and allowed a shot but very weak. I changed the spring to a brass egg shaped one and no more problem.Until I changed springs I used a few drops of Mac1 secret sauce on the felt before each shooting session. What I found odd was the sauce provided sealing effect boosting performance until i swapped out the spring, now I can use 6 pumps with no issues.Another factor to consider if there are no leaks and arm adjustment does not help is how easy the new grooved compression chamber slid into place, if it relatively easy with minimal resistance you may need to up size the outer o-ring as it should provide slightly harder resistance to create a solid seal between the tube and brass compression chamber. Also tightness of locking nut that holds exhaust valve in place if you can turn 1/4 to a half more that should provide adequate pressure for the seal that seats between the exhaust valve body and air compression chamber.Any of the above would cause the easy initial pumps but will allow for some stored air with each pump and if there is no detectable leak these areas will most likely be your issue, my bet will be you need to up size the outer o-ring for better seal.
This is a little embarrassing but I should share what I found so others won't think the newer design is faulty.I damaged the leading edge on the exhaust body when I was tightening the nut. I was in a hurry and didn't have the rod in the exhaust port during initial tightening so I dinged the sealing edge on the body. It would hold air until the pressure was higher and would overcome the seal. I have replacement parts on the way. Live and learn...
Thanks for the detail Gary! Maybe this will help others (me) from making the same mistake.