OK motor gurus, I was rebuilding the carb on my 20 Nissan 4 stroke. That all went pretty smoothly and it sure was a mess, I'm glad I got the kit for it. So, I got it all done and was trying to pump up the primer bulb and it wouldn't pump up. Its new and I knew it worked because I had tried it just to see if I could get the motor running about a month ago and gas was pouring out of the motor. The motor had sat for about 2 years according to the guy I bought it from. I'm thinking there was a bad fuel line inside the cowling or something, there was one cracked around the barb on the fuel pump so I temp fixed it. Tried it again and no go. Pulled the lines apart in the various unions and there was air going through the line when I pumped it. I'm thinking wtf is going on? There was a full 3 gallon tank in the bow. I go and pull the tank....fricking empty. The tank was strapped down there was no fuel in the boat (no sole) there was no fuel on the ground. The carb was full when I pulled it off. I check the oil and there was fuel in it of course. I drained it and there was about 2 quarts probably. The crankcase holds 1.2. My question is where the hell did all that fuel go? No way it evaporated that fast. It didn't noticeably leak anywhere. Did someone siphon it out and not spill a drop? That would be kind of hard to do without pulling the tank out. Then you put it back and strap it back down? Why not just take the tank? I don't understand....obviously :-/ Thanks in advance for any help.