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    2020 Pyramyd Air Cup - CANCELLED

    You're not alone. The Experimental Aircraft Association's "Airventure" ("Oshkosh") fly-in was cancelled too! >In the meantime, stay safe, have a great summer and we’ll see you in 2021. I hope so, but our masters and rulers are conjuring up all kinds of scary stuff and new despotic dictatorial...
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    Hill Mark3 Pump Rebuild Question

    All the more reason to stick with the OEM greenie until something better comes up. I usually pump to only 3000 psi but I did take the Viton V90 up to 4000 with a dead head hose plug to test it. Though it was just a brief test, I think it might have started the Viton V90 downhill, because it...
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    Hill Mark3 Pump Rebuild Question

    I'm playing with regulator shim stacks so I'm doing a lot of pumping on my Mk4 and I have plenty of opportunities to try new piston o-rings. The last Viton V90 didn't last very long and the x-ring ebay seller never responded to my question about durometer so I decided to just try a FKM 75...
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    Hill Mark3 Pump Rebuild Question

    Yes--the green OEM ring sold by Hill is tough to meet or beat, because you need a shore 90A durometer o-ring to not fail fairly quickly from extrusion. Perhaps if you don't run the pump at very high pressure very often, you might get away with less than D90 . Also you'll probably want something...
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    Hill Mark3 Pump Rebuild Question

    This thread is a bit old but I figure people will always have a need for pump repair information. I too am a heavy Mk4 user. Funny, but I've never replaced #18 in that diagram. I got my pump about 4 or 5 years ago and only pumped it a few hundred cycles before it quit working (no compression /...
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    Beeman P17 Trigger

    As I recall on my P17, the screw didn't do anything because it would not screw into the trigger shoe far enough. Right from the factory, the screw seated on a counter bored ID "shelf" in the trigger shoe too soon to be of any use. Rather than trying to find a longer screw, I recall that I had to...