Hi this is my first post. I have lost the little piston that goes into that base plate of my hydraulic pump (hyc-5005) I had discovered the spring that is inside with the piston to have collapsed on itself . The spring was $1.82 (487-490) and would have fixed the problem. However no one has a part number for the piston so no one can find it for me. I have found new base plates but of course do not have the spring and piston inside. No piper parts illustrations have the piston listed. Anyone have any info or advise as my Seminole has sat idle for way too long. Picture of the illusive piston is in the attached picture.