there is a valve I think most have use a round knob to turn it near or underneath the seat , that controls the volume of flow threw the 3 point system,I believe most people leave them just partially open
I will try the knob again, although it didn't seem to help the situation when tried before. However, I've come to understand that this valve needs to be adjusted in very small increments on these Jinma tractors. Maybe there is a “sweet spot” that we need to hit?