And that connector (which goes into the sleeve) also wants a new gasket. First, I overlooked that and there were still a some occasional drops dripping out. No idea, where to get the right gasket (2nd from top), but I did have FKM seals OD 29mm CS 3.5mm (=diameter). I tried that, but it was too thick, thus I thinned it down with an angle-grinder (1st from top thinned down too much, 3rd from top was OK. While I hope, that this seals suff, I also ordered already cheap FKM seals ID 22.4mm CS 2.65mm