Sorry, I've been taking treatments for cancer and haven't been to storage unit for a while to pull service grams. Have you tried minnpar.com for the kit? There should be a dampener in the valve, might have a plugged orfice, if it worked ok before, probably had correct orfices. sg kit would have slightly different size orfices for smoother operation. Try minnpar first in case they may have it or maybe tech help can get one from HUSCO or at least find out what is different. Could be orfice in a spool plugged, both spools have to work at the same time for smooth operation, it would be unusual for two sections to act up at the same time so that pretty well isolates it to the inlet or outlet that controls both bucket and boom.