Having kept it working for the last 5 years using Power Steering Stop-LeakI fitted a new O ring to my 25 year old Halfords 3 ton floor jack that was leaking from pump piston I followed this YouTube video The O Ring fitted on my jack were 14mm ID 4 mm section Nitrile bought in a pack of 5 from eBay.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)