Hi John jay, tanks higher than piston heads so no low pressure. In the Uk we don't really use buckets. There are two large drip trays that the piston sit in. I'm working on the theory of a a relaxed seal on one side. Maybe out of plumb? I have a 3rd party hydro specialist doing a repack on Monday. I found out that this is the 3rd re pack in 4 years and the second in 12 months. Something is not right