I know mine wouldn't lift the door when one of it's two springs broke, but it's a heavy door!
Actually, when I got the springs replaced, the door actually rises with only about a pound or two effort now.. It's pushing it down that the opener has to actually work..
I've got a 3/4 hp Craftsman chain drive..
My dad rigged up a block and tackle pulley system to lift up his hard tonneau cover (that thing is HEAVY!) but it needs two people to pull on opposite sides..
Sounds like a neat idea if you can make it work... Good luck!
Mitch
