Hi, I just bought an old Coleman 505 and I am completely new to camping stoves. I can't seem to be able to make it work : after pumping about 40 times and starting it like it says in the instructions, no gas seems to be coming out and I it doesn't light up when I put fire on the stove. I am using Coleman's camping combustible and the tank cap gasket seems to be in very good shape. I think the problem might be with the pump. What happens is when I unscrew the pump a bit and start pumping, it doesn't become harder with time. But when I remove the tank cap gasket, it still makes a pressure releasing sound, so I guess there is at least a little pressure going in (maybe not enough?). So I tried removing the pump to see if it looks normal and everything seems to be fine (to me, at least). I added some lub and put it back in, but the same problem happens. Here are some pictures so you guys can see what I am talking about. Thank you in advance!