So my car is overdue for a coolant change and instead of making a mess and pulling the lower rad hose, I figured I'd use the drain on the radiator. I got the thing to turn but only about 1/4 of a full circle. It's got to open more than that right? I'm not getting any kind of coolant out and if I try and turn it any farther, the ratchet just slips. Thoughts?

Ratchet? In my experiance there was just alittle plastic "nobe" you can get with your fingers/hand. Also take the cap off the overflow tank, it'll help it drain quicker.

yeah, the plastic petcocks in the rads suck. never been able to get mine out.

Yeah if you use a ratchet and and one of those adapters for the smaller sockets it fits right in. There's also a spot for one of the hex bits that I can get in there as well. No thumb screw of any kind. I finally got fed up with it and pulled the lower hose.