winch
If you look at the pinion shaft, a regular winch will have nothing other than the handle and a small gear on it, if that's the way yours is look for a release lever or a pawl that can be slipped back to free the wheel.
A brake winch will have a couple other 'gadgets' (besides washers and bushings) on the pinion shaft,
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_23063_23063
Shows a brake winch, between the pinion and handle there are a couple other deals, some have the vrake assembly under a cover right under the handle. If you have that kind it just takes reverse cranking on the handle to let it down, depending on how long it's been up it may take a bit of effort to release it.
If you ever have to replace yours, and can use one this is the type to get it's much safer and conveient to use. (brake winch, not that particular brand/model)
It does seem to take as much effort to let them down as it does to raise it, but it won't get away from you.
Ken.