Massey Ferguson 0A.43.1B: External Hydraulic Valve 4 Issue

Malfunction or fault associated with the fourth external hydraulic remote/spool valve. Often electrical or connection-related, though it can also be caused by mechanical sticking or jamming.

• 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 wiring harness and electrical connector at External Hydraulic Valve 4 for loose pins, corrosion, or damaged wires.

2. 2

   Check for hydraulic fluid leaks at the quick couplers, hydraulic hoses, and the valve block itself.

3. 3

   Check the hydraulic fluid level and condition for contamination like metal shavings or dust.

4. 4

   Verify if the valve is physically sticking due to debris or internal wear.

1. 1

   Relieve Pressure

   Turn off the tractor and relieve all hydraulic system pressure by cycling the hydraulic levers/controls before beginning work.

2. 2

   Disconnect Electricals

   Disconnect the electrical harness connected to External Hydraulic Valve 4.

3. 3

   Remove Hoses

   Place a catch pan underneath the valve block. Disconnect the hydraulic hoses and quick couplers attached to the valve.

4. 4

   Unbolt the Valve

   Remove the mounting hardware securing the spool valve to the lift cover or main hydraulic block.

5. 5

   Clean and Inspect

   Clean the mounting surface. If the issue was purely a leak, replace the O-rings/seals. If the valve is electrically dead or internally jammed, prepare the replacement valve.

6. 6

   Install New Valve

   Mount the new hydraulic valve and torque the bolts to OEM specifications.

7. 7

   Reconnect

   Reattach the hydraulic hoses and plug in the electrical connector.

8. 8

   Fluid Maintenance

   Top up the hydraulic system with OEM-spec UTTO fluid (e.g., 10W40) and replace the hydraulic filter if contamination was found.

9. 9

   Clear Codes

   Use a compatible diagnostic tool to clear the 0A.43.1B code from the system and test the remote valve for proper operation.