On these small post-war Montblanc piston fillers the inner tube carrying the piston thread is not screwed in but press-fitted into the barrel. It can therefore be neither unscrewed nor prised out; force will as a rule damage the barrel. For the dismantling there is a special tool which clamps the piston knob and then allows tube and barrel to be drawn apart along their axis — the principle is that of a puller for roller bearings. Without this tool the repair can hardly be carried out sensibly.
A pen with a broken piston thread therefore belongs with a workshop that specialises in old Montblanc piston fillers, where both the puller and the right spare parts are to hand. Makeshift solutions using parts from other models rarely answer: a piston knob from the larger 34 will screw into the 24, but it does not finish flush there and leaves a gap of several millimetres. Whether the upper barrel sections with the ink window are interchangeable between the models 22 and 24 has never been settled and should be checked before any parts are bought.
