Originally Posted by jvminner
...sounds like the purge ball gets stuck on the edge of the port.
That's what I was thinking, too. If you still have a chinese hookah, you might be able to scavenge the purge cap and ball bearing and use them. They're larger than most syrian rigs and, as often as not, use the same threads, so they fit. I have four syrian hookahs (two Nour and two Al Narwas) and I converted all the purge valves like that. They work MUCH better.