mrkmrk,you have the best powrscrew vice i've seen unrestored. i noticed in first picture the jaws open & handle piston screwed in that would indicate it is out of fluid , the other pin sticking out on one side is a stop to limit travel when out of oil, most get shered of & the piston handle gets jamed in. if you want to get hydraulic working take lock bolt out of bottom of the front jaw & unscrew the main screw & handle assembly out of vice on the big part is the cylinder it has an allen plug remove it this is where you add oil gear oil is good, with lead screw looking up screw handle in start adding oil while unsrewing handle slowly when at end of travel out screw back in you should see air bubbles, just keep going back & fort while adding oil on back stroke & air out on forward stroke, all air must be out or it will not work. did mine like this works beautiful. good luck . yours looks so good i wouldn't take it apart just try this.