I've never tried rebuilding. I build PC's and am fairly handy/do-it-yourself-er, so it doesn't scare me, but I don't even know where to begin with materials and methodology. Where should I start?
I had the same exact issue when I first got my Nautilus, the heads that came with the device were both basically useless. They had NO flavor what so ever unless primed first, which was horrible. After ordering a pack of five heads, 3 worked great, 2 had the same issue. It seems to be hit or miss with the heads, but when you get it working, its the best taste and vape experience I've ever had. The heads just seem to die quick for me.