Massey Ferguson A.23.18 – Mid Mount Valve Module or Hydraulic Control Module: External Hydraulic Valve 2 Issue

Malfunction in the second auxiliary/remote hydraulic spool valve circuit. The underlying condition typically involves restricted oil flow, a failure to generate or hold pressure, a stuck spool valve, or an electrical fault such as a connection problem or an out-of-range value from the spool position sensor.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S

1. 1

   Fluid Level and Condition Check: Verify the hydraulic fluid level. Check if the fluid is dark, smells burnt, or has a milky appearance (which indicates water contamination).

2. 2

   Filter Inspection: A partially blocked hydraulic filter can restrict flow to the system, causing the valve to respond sluggishly and trigger a fault.

3. 3

   Visual Leak Inspection: Check for external leaks at the quick couplers, hoses, and the valve block itself. Even a slow seep can rob the system of pressure.

4. 4

   Electrical/Sensor Check: Inspect the wiring harness and connector going to the External Hydraulic Valve 2 spool position sensor for corrosion, damage, or loose connections.

5. 5

   Pressure Test: Use a hydraulic gauge at the remote coupler to determine if the issue is a lack of pressure (pointing to a pump or relief valve issue) or an isolated valve failure.

1. 1

   Secure the Machine

   Lower all implements to the ground, turn off the engine, and relieve all hydraulic pressure by moving the control levers back and forth.

2. 2

   Drain/Flush Fluid (If Contaminated)

   If the hydraulic fluid is degraded or milky, drain the system completely and flush it.

3. 3

   Replace the Hydraulic Filter

   Remove the old transmission/hydraulic filter, clean the mating surface, and install a new OEM filter.

4. 4

   Service the Spool Valve

   Disconnect the electrical harness from Valve 2. Unbolt the external hydraulic valve from the valve block/lift cover. If the valve is mechanically stuck, it can sometimes be disassembled and cleaned. However, if the internal seals are blown or the spool position sensor has failed, the valve assembly must be replaced.

5. 5

   Install New Components

   Mount the new or rebuilt hydraulic valve, ensuring all O-rings are properly seated to prevent internal pressure loss. Reconnect the wiring harness.

6. 6

   Refill Fluid

   Refill the system with fresh OEM-spec UTTO (Universal Tractor Transmission Oil).

7. 7

   Clear Codes

   Use a compatible Massey Ferguson diagnostic interface tool to clear the A.23.18 / 0A.2X.18 fault code from the system.