I assume this is a new issue and hasn't been consistent since you started the machine. On older counter pressures I messed with, it was usually bad poppets on the vacuum evac circuit, or fob issues between fill and seaming/crowning. I also found I like positive displacements pumps better than diaphragm or impeller.
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Steve Saunders
Owner
Woodberry Fabrication, LLC
White Hall MD
(443) 992-5634
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