tbran
Guest
when the lower switch is energized 12v goes to the lower coil only - make sure only one coil is energized a shorted wire will energize raise and lower at the same time. The coil is then energized and the primary poppet is pulled off the seat allowing oil to unseat the second stage poppet which is the determinate of header lower as travel is limited by the adjusting screw. Now either the flow through the valve is limited by obstruction, or the second stage poppet is not moving due to trash OR the oring in the bore of the blokc is sticking the second stage poppet. This oring had been replaced by a square cut oring to prevent binding. Either way replace it as it is on the outside and easier to get out and repair. Finally the possibility of a restriction in the metal lines such as a pinch is possible as well. Hope this helps.