@The Warrior I cleaned the tank out, removed the generator, cleaned it and replaced the brass gauze, put some carb cleaner in the open valve and let it soak for a while, put it back together and it works as shown.
I wondered. I found a tutorial on the Coleman forum to repair these just yesterday: How To Rebuild a 530 GI Pocket Stove - The Coleman Collectors Forum
If you do take it apart be carefull with the screws holding the frame to the tank, lots penetrating oil and a good quality screw driver to fit the screw heads, OCP has replacement screws, it might pay to fit new ones if the heads are chewed on the ones you have. That tutorial was handy when i took my other one apart.