Massey Ferguson 0A.40.20: External Hydraulic Valve 4 Issue

Indicates that the tractor's onboard diagnostic system has detected a fault, restriction, or connection problem specifically associated with the number 4 external hydraulic remote/spool valve. Symptoms typically manifest as remote hydraulics that are slow, weak, or completely dead (unresponsive).

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Inspect the hydraulic oil filter and transmission filter for blockages, which can restrict flow

2. 2

   Check the hydraulic oil for dirt or contamination

3. 3

   Inspect couplers and hoses for blockages, damage, or wear that could cause pressure-related faults

4. 4

   Check if the spool valve is physically stuck, which can cause slow response times or complete system failure

5. 5

   Verify the operation of the tractor's PTO shaft and pump drive (a sheared PTO clutch plate can mimic a valve or pump failure)

1. 1

   Attempt Manual Release

   Try to unstick the valve by manually moving the pump control valve lever back and forth.

2. 2

   Cycle the Lift Arms

   If an implement is attached, you can sometimes free a stuck valve by repeatedly picking up and dropping the lift arms while the lift control levers are in the down position.

3. 3

   Remove the Valve

   If the valve remains stuck or the electrical connection/solenoid has failed, remove the control valve body from the hydraulic cover.

4. 4

   Clean or Rebuild

   Thoroughly clean the valve to remove debris. If internal seals are blown or the spool is scored, rebuild it using a spool valve repair kit.

5. 5

   Replace if Necessary

   If the valve cannot be salvaged or the electrical pins are damaged (common on electric spool valves), replace the entire spool valve assembly.

6. 6

   Reinstall the Valve Body

   When reinstalling the valve body, ensure that the stack pipe (tube) is properly engaged in the pump at the bottom. If it is not seated correctly, oil will be pumped straight into the transmission instead of pressurizing the valve.