Case IH 1943-07 - UCM – UCM: UCM: Rear pilot head #3 reporting that the spool valve is stuck

The Universal Control Module (UCM) has detected that the main flow control spool inside the #3 rear remote valve assembly is physically sticking or seized in its bore. This condition is almost always caused by hydraulic system contamination.

• MAGNUM AFS Connect
• Puma Series (165, 180, 195, 210, 225, 260 CVX)
• Steiger Series (400, 500)
• Quadtrac Series (470, 500, 620)
• Magnum Series

1. 1

   Inspect Hydraulic Filters & Bypass Valves: Verify that the transmission/hydraulic oil is clean and that filter changes are up to date. Check that the cold oil relief cartridges are properly in place at the bottom of the filters; if they are missing or damaged, dirty oil will completely bypass the filters and go straight to the system valves, causing the spools to stick.

2. 2

   Verify UCM Voltage: Ensure the UCM is supplying the correct reference voltage (typically 5V) to the pilot head sensors without dropping out of range.

1. 1

   Locate valve section

   Locate the #3 rear remote valve section on the rear axle housing.

2. 2

   Remove end cover

   Remove the end cover located at the opposite end of the remote valve section from the pilot head assembly.

3. 3

   Save O-rings

   Carefully remove and save the two O-rings found under the cover for reuse.

4. 4

   Extract spool

   Carefully extract the main flow control spool from the remote valve section.

5. 5

   Clean spool and bore

   Clean the spool and its bore to free it up. CRITICAL: 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. Use brake cleaner and a soft brush to clear the contamination.

6. 6

   Lubricate and reassemble

   Lubricate the cleaned main spool (or a new improved main spool) with clean hydraulic oil and reassemble it into the valve section.

7. 7

   Reinstall O-rings

   Reinstall the two saved O-rings.

8. 8

   Install cover

   Install the valve spool cover and tighten the six cover screws to 27 - 31 Nm (19 - 22 lb-ft).

9. 9

   Perform calibration

   If the pilot head itself was damaged and needs to be replaced, you must perform an on-board valve calibration (Channel 1 - Valve Calibration) via the UCM "HK Menu". This requires special tools: a pressure transducer and a jumper harness.