It appears to have a set of friction plates (braking?), maybe once there is a load on it, it'll unwind. I'll find out this weekend.
Thanks for the Help.

Hello, I am new to the Sailing lifestyle (also to this type of Forum) and recently purchsed a 1986 25' MacGregor. I am replacing the cable to raise the keel, but I do not get the way the winch works to relase the keel. My winch only takes up the Cable. How do you get it to release? there is no lever...