My Vandercook sp-15 has developed a weird quirk with the connection between the paper grippers and the foot pedal used to activate the grippers. When I step on the pedal, I have to press down harder that I used to in order to get the grippers to raise, and there is a loud metal kind of click/clunk as the paper grippers raise. It sounds like the sound is coming from the left side of the press.
Thanks in advance for any advice!
The clunking sound probably emenates from the cam shaft that passes through the impression cylinder.
The gripper pins and cams become worn after decades of contact. Fresh contacts need to be established. To do this, rotate the shaft by hand, then depress the pedal and rotate each gripper head by hand. It may require removing the gripper bar to inspect the round ends of the pins. Excessively worn pins will need to be replaced.