We have two things going on with ours. It doesn't come up for a minute or so then it shudders up the flies the rest of the way up. It now has very little control going down. One second it dropping a few inches then it will drop all the way down if you try to lower it another inch.
Thinking it was water in the sump I pulled the plug a little and got a small amount of water to drain. But nothing changed.
Kioti CK3510SE HST, Ford 3400, Gizmow ZTR, Simplicity 7016H
My 3400 pto filter is in the rear.. pull the seat and plate under it. The loader filter is in the lower left upright. Theres a plate that unbolts from the bottom.