Have you opened it up yet? I would use a penny to remove the small slotted nut on the inside of the drag knob. From there, unscrew the drag knob all the way, and the center spindle can slide right out, thus separating the spool from the frame. Once open, you will see the pawl and how it engages with the machined drag plate.
The pawl clicks in one direction (when reeling in) and locks into the drag plate in the other direction (outgoing line). That's when the cork is at work on the smooth surface at the bottom of your spool and applying the brakes.
If your drag is totally backed off, there's no tension between the spool and the cork, so there's nothing to make that pawl click like you'd want it to. It's just a matter of pressure on the drag plate.
A couple of turns of the drag knob and the pawl will sing to you. Then you know the cork is engaged against the underside of the spool.
It really is a simple, yet well designed, system. If you haven't checked it out, open her up.
In the reverse, use the same penny to tighten that slotted nut at the end, and you're good to go.
Some folks don't like the Abel reels because there are a couple of parts at play when you take them apart. I wouldn't advised removing the spool when you're out fishing, because it could be easy to lose that nut.
There's really no reason to take it apart in the field unless you're changing spools, in which case you should use great care not to drop that nut in the water or in the rocks.