Arty PP750...junk o-rings

Hello --

Figured I got grit in the check valve as leaking through the fill port so just shot cans until the pressure dump. Spun off the air tube and then the manometer end ass'y to get at the check valve. On the way scalloped the air tube o-ring (illust p/n #49), I thought. Actually, the o-ring delaminated...so these are not solid Buna rings...just junk.

Fortunately, a couple of you PP750 owners have posted your o-ring lists, for which I am very grateful. 

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