Blown Head Gasket

My '92 Ranger has blown the head gasket, and it's gonna cost at leat a grand

...I found this crap on the internet though that says it seals the gasket without having to take anything apart. I dunno though, sunds too good to be true. The stuff is called Crackd Leak Cure and is at http://www.detsco.com/clc/index.htm
Think it'll work?

I thought mine had that problem. Turned out to be a broken head bolt. Of course the head gasket needed to be replaced as well. Not a funjob, but sealers didn't do it. :(

How bad is it leaking?

I'm not sure if that stuff would work or not, but I do know some of those kinds of things work. My truck has a crack in the block and it kept leaking coolant through the crack in the block into the oil, I put some stop leak in it and it hasn't leaked a drop in 10,000 miles. It's one of those risks you have to decide wether you want to take, it might work, it might plug something up and cause problems. If it works you save a grand (at least for now), if it doesn't you're out five bucks (or whatever the stuff costs), if it causes problems you could be out more than a grand depending on what the problem is.

Good luck