Charcoal Canister with no purge?
 

I'm doing a vent line on my truck, and I need to replace my charcoal canister, because it has a hole in the side, top is broken & pitted from battery acid.

Anyways, so I went to the junkyard and picked up this unit of an 80's GMC 1/2 ton:
http://i59.photobucket.com/albums/g3...a/IMG_2907.jpg

I grabbed it because I was in a bit of a hurry, it's the right size, and it has 2 lines which is all I need. Originally, the cans had 1 valve coming from the tank, 1 valve from the carb vent bowl (no longer need since it has an edelbrock now), and 1 to the PCV to suck the fumes out. But this one just has 2 lines, labeled "tank" and "carb". So I'm trying to find online if one of these is a purge valve, with no success. It was used on a bunch of cars and trucks, but I have yet to see a PCV diagram for one showing how it's hooked up. It doesn't seem like it would work if it was just the fumes from the tank & carb just go in there to sit. They have to go somewhere. I'll be going back to look for another, but if this one works, it would be great.