It's been a while since I did it but IIRC it would work but only if I made pretty extreme movements of the valve lever. If you think about it the valve should work with only a relatively small movement of the lever since the torsion bar itself doesn't move that much. If the valve only works with a substantial (say 1-2" movement) of the arm then you probably have the cam in backwards. Also, if you do a reassembly be sure you got the large ball bearing on the correct side if the piston so it can seat itself properly. You should be able to see it if you open the access hole that has the copper washer.
I have to admit that I suspected I had the cam on 180 degrees reversed as I had an Uh-Oh! moment on reassembly when I realized it was possible to install it two ways and I'd paid too little attention when disassembling to know what was right. The good news is that the job went much quicker the second time.
