I have a Coleman 4M camp stove that has seen little use since it was made (1962?). I believe my dad tried it once to see whether it worked. That's it. It sat in my dad's garage for the first 30 years, and then my garage for the next 30 years. There is liquid fuel in the tank (more than half full?) that has probably been in there since 1962. Really. I tried to pour it out (after removing the filler cap), but only a few drops came out. I've tried to open all the other valves but that doesn't seem to help. It seems like the liquid must be in a separate compartment. What am I doing wrong? As should be apparent, I know nothing about these camp stoves. Also, what else should I do after I remove the old fuel and try to get the stove working again with fresh fuel? Any other tips? My 9-year-old son is eager to try cooking with the stove. Thanks!