The open-center system constantly pumps oil through the hydraulic cylinder operating valves and returns the oil to the reservoir. The closed-center system does not pump oil until there is a demand for oil from one of the hydraulic cylinders. In this case, CLOSED-CENTER means that when the operating valves which control the hydraulic cylinders are in the neutral position, there is no flow of oil through the valves. As long as the engine and pump are running, a constant stand-by oil pressure of ap

See item 30 at the end. 26. Worn control valve - replace the control valve. 27. Check poppet in the control valve not holding - clean check poppet(s) carefully, being sure that it moves freely with good spring action and seats properly or replace. See item 30 at the end. 28. Damaged or worn spool seals - replace spool end seals, see item 30 at the end. 29. Ball in anti-cavitation check valve is stuck or not seating properly - clean anti-cavitation valve carefully, being sure that checks move fre

Store lockpins in holes provided in operator platform. 2. OPERATE from the backhoe operator’s seat only. 3. LOWER the stabilizers until the rear of the tractor is totally supported by them. NOTE: rear tires should not come up off of the ground. See diagram on Page 11. 4. DO NOT dig near the stabilizers. 5. DO NOT touch overhead wires with any part of the backhoe. 6. DO NOT attempt to raise the tractor off the ground or move the tractor forward or backward using the backhoe dipperstick or bucket.

lbs. torque to tighten assembly screw on spring centered bonnet assembly. 8. At the FRONT of the valve remove all parts connected to the spool (handle, linkage, etc.). 9. At the FRONT of the valve remove seal plate retainer, seal retainer, back-up washer and spool O-ring seal. 10. Thoroughly clean counterbore. 11. Lightly oil new O-ring seal. Slide O-ring seal over valve spool and insert in seal counterbore. Replace back-up washer, seal retainer, and seal plate retainer. 12. Reattach all parts c