Mike, On a Nazel there is a spring arrangement that is part of the idle circuit.The light spring closes a poppet valve that gets the ram to stay at the top and park there, and it bypasses the air that would send it down. Bob Bob Bergman Postville Blacksmith Shop N8126 Postville Rd Blanchardville Wi, 53516 608-527-2494, fax 608-527-6908 www.postvilleblacksmith.com www.KA75.com>