Hello again all, been a while... and so has usage of my RWS pump.
Basically, I can start to pump, but within a couple of strokes, when pressure builds, it becomes impossible (ever harder) to lift the handle. It just sucks down, in reality I would say that the downstroke pressure is leaking to the top part of the piston thus pushing it down.
I don't wish to take it apart any further than necessary so if anyone can advise which part, presumably some o-ring, I need to replace, and where it is found, that would be great.
Thanks in advance.