My dear FPN crew, I'm a little frustrated. I found this beautiful Kaweco Dia 803/08 on Shpok (online flea market app essentially). I first cleaned it and flushed, and soon noticed that the cork must've shrunk over the years. I sat it in water for a few days, which couldn't revive the cork's functionality. So I tried to look up how to change the piston, and found out through this video, how to actually screw out the piston unit. Timo also pointed out in the video (at around 3:48) that unscrewing this part would prove to be quite difficult, because it's quite small. I already saw that people might have attempted unscrewing it with pliers as it looks a little scratched. I've been trying to screw off the part with nylon pliers - but without success. Can anyone help me? Does anyone have a helpful piece of advice? Also, if anyone could help me out with the year of production, that would be amazing, too. http://66.media.tumblr.com/8984c5c4fcf2de732db5bbc24952ced8/tumblr_od2uo0kBwB1vo6rxoo1_1280.jpg