My guess is that you have a blown o-ring on the 3-point piston. You need to remove it and check the o-rings (this piston is under the seat) Do you have a parts book ? We have a rebuild kit for it.I see you are a guest,pay the $ 15.00 and join you will get your moneys worth of information off here
Let me know if we can help
Tommy
Affordable Tractor Sales
“Your Jinma Parts Superstore”
http://www.affordabletractorsalesco.com