sticking Actylene regulator

Hello everyone,

I'm having an issue with my H-F acetylene torch rig. After nearly a
year of non-use, I fired it up over the weekend. Ox side was fine and
working exactly as expected. But the Act. regulator is having the
following issues:

1. With the regulator t-handle unscrewed completely, open the tank
valve, line-guage pressure starts creeping up.
2. With the tank valve open, screw in the t-handle to 4 psig. Does not
hold at 4 psig, starts creeping up.
3. With the tank valve open, screw in the t-handle to 4 psig, light
and adjust the torch, will sorta hold the pressure at 4 psig. But as
soon as the torch valve is closed, act. pressure starts creeping up.
4. Unscrew the t-handle, open the torch valve to vent the line,
pressure drops to zero. Close the torch valve, pressure starts
creeping up again.

Now I'm assuming that something in the act. regulator is "stuck open",
otherwise uncrewing the t-handle and venting the line pressure should
drop the line pressure to zero and keep it there. Also, if something
weren't stuck, the reg should hold the line pressure where it is set.

Now my question is, what to do about that? Can the reg be serviced,
and if so, how do I do it? Anybody have any experience in this area?

Thanks,
Harry