I have recently bought a vintage Waterman 92 (see pics). Pen was said to have been serviced and new sac installed. The only apparent flaw I saw was the broken head on the lever - the lever still works fine. However, after I inked it up (Diamine Green/Black for reference), I noticed that it was easily the wettest pen I have written with. I barely shook the pen forward and what had to have been half the ink in the sac fell straight out onto the paper. I did the same to produce the ink drop in the pictures.
I will be disassembling the pen shortly - I hope I don't find that the feed is destroyed or something. I can imagine this is a fairly common problem with old lever-filling sac-pens. Is there a fix?