Case IH 1967-07 - UCM – UCM: Rear pilot head #5 reporting that the spool valve is stuck

The electronic actuator (pilot head) controlling the #5 rear remote hydraulic valve is unable to move the internal spool valve. The spool valve is physically jammed or binding in its bore, almost always caused by hydraulic oil contamination.

• MAGNUM AFS Connect
• Magnum
• Steiger
• Puma
• Optum

1. 1

   Inspect the hydraulic/transmission oil for visible dirt or debris (contamination is the primary reason pilot spools stick).

2. 2

   Check if the cold oil relief cartridges (bypass valves) are properly in place on the bottom of the hydraulic filters.

3. 3

   Inspect the wiring harness and connectors going from the UCM to the rear remote block for water or dirt intrusion.

1. 1

   Locate the Valve

   Identify the #5 rear remote valve block at the rear of the tractor.

2. 2

   Remove the Pilot Head

   Carefully unbolt the electronic pilot head (actuator) from the valve body to expose the spool valve.

3. 3

   Extract the Spool

   Remove the return spring and plug.

4. 4

   Clean the Bore and Spool

   Use a toothbrush and brake cleaner to flush out the spool bore. Do NOT use any abrasives (like sandpaper or emery cloth) on either the spool or the spool bore, as this will ruin the tight machining tolerances.

5. 5

   Reassemble

   Once the spool moves freely in its bore, reinstall the return spring, plug, and pilot head.

6. 6

   Address the Root Cause

   Drain the contaminated hydraulic oil. Replace the hydraulic filters and ensure the cold oil bypass valves are installed correctly so the system filters the oil properly.