I bought a used SEITZ jeweling press off of Ebay a couple of weeks ago that was sold as a “buy it now” at a cheep price. When I looked at it, it appeard to have been in someone’s garage for the pase 30 years. The exposed metal on the frame was badly oxidized and one of the pump pushers was stuck in the plunger rod. After cleaning the exposed metal parts with Scotch Brite and hydraulic oil, I then tried to remove the pusher with no success. I tried penetrating oil and twisting with pliers and it wouldn’t budge. As a last resort I held the plunger over a gas flame on my kitchen stove and then twisted it out holding it in a set of pliers. That finally did the trick and the pusher twisted out of the hole undamaged. It had probably been stuck in there for the past 30 or so years.