Has anyone ever fixed the hydraulic block that controls the pea auger on these headers. The pea auger stays at one constant speed, the control valve on the block does nothing for it. I’m 99% sure the hydraulic block is my issue but JD wants $1100 for it. Would it be a simple fix to take it...

we purchased a 635 fd head and were told our 9760 sts would lift it, it has the 70 mm lift cylinders. whats the best solution?