I bought this pump at least 6 months ago, for my Beeman Chief 1322 PCP air rifle.It has performed very well. Nearly flawlessly,... w/ explanation.My Beeman gets used daily in combatting a cal. ground squirrel problem on my property; seriously, daily. I start the day by pumping it up, and putting it out to where i use it. This pump gets used every single day.A few weeks ago, I started developing an issue where the pump wouldn't pressure up. I'd bump it on the floor (carpeted), and, whatever was not working was knocked free.For those not translating the instructions well, this is what they call "sewage".I figured that the top or bottom valves were not seating, and would look into it, eventually.Well, "eventually", came this week, and finally, today.I developed an air leak, that my wife could hear, but my rock and roll ears couldn't. But I could feel the leak.I removed the main tube from the black pressure distribution box base, and had a look around.The instructions showed well enough how to access the bottom one way valve, so, I replaced that O-Ring and Spring, and closed that end of the main pump tube.I unscrewed the top of the main tube, at the handle, and pushed out the retaining pin, and, replaced the rubber ball at the top, and reassembled the top end.I did not open the deeper inner workings of the pump, just the outer seals shown in the photo illustrations.These replacements were extremely easy!Now for the upgrades:I was able to improve greatly on how the main pump tube seats into the black pressure box by going to the hardware store, and fitting a conical washer with a thru-hole into a space where the manufacturer had stuck two round o-rings together, in order to fill the space, and create a seat/seal between pump and distribution box.This is an area where they could greatly improve the product. But it is an extremely easy DIY upgrade with a trip to the hardware store, and the Lasco O-ring drawers.This conical rubber washer filled the void perfectly, as an ideal seat, and was just the slightest bit thicker than the two stacked o-rings. The base of the pump mechanism is machined flat. The top of the conical washer is machined flat. The two mate perfectly, with a nice touch of compresion on refitting them together. That touch of compression forces the conical end into seating interface with the black dist. box pump base. This is many times superioir to the OE assembly. The conical washer is a single piece that perfectly fills the bottom of the interface bore, and creates the perfect seal for the main pump tube interface. It is similar to the conical washeers used in hose bibs in homes/yards, but, larger.Pump overhaul and upgrades in place, I tried to pressure up using the supplies pressure test plug. Bupkis. I was still blowing pressure out.So, I looked at the Foster quick connector fittings on the hose. I look down into its depth, and find a mashed up O-Ring that was distorted by the interface with the male quick connect nipple.On closer ins