Massey Ferguson A.21.11 – Autotronic 5: External Hydraulic Valve 2 Issue

Malfunction in the auxiliary/remote hydraulic spool valves. This can be caused by improper hydraulic system pressure (too high or too low), fluid aeration, a failing solenoid, or internal leaks/seal degradation within the valve body.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 5400 series
• 6400 series
• 7700 series

1. 1

   Check Hydraulic Fluid Level: Low fluid is the most common cause of sluggish or failing hydraulic response.

2. 2

   Inspect Fluid Condition: Check if the fluid is dark, smells burnt, or has a milky appearance (indicating water contamination). Degraded fluid loses viscosity and can trigger valve faults.

3. 3

   Inspect Hydraulic Filters: A clogged filter (even 70% contaminated) restricts flow and forces the pump to work harder, which can cause valve actuation issues.

4. 4

   Test System Pressure: Use a hydraulic pressure gauge to test the system. Pressure that is too high (above 3600 psi) causes oil overheating and seal damage, while pressure that is too low (below 2200 psi) results in a lack of power at the external quick couplers.

5. 5

   Check for External Leaks: Inspect the valve body, couplers, and hoses for seeping fluid, which robs the system of pressure.

1. 1

   Relieve System Pressure

   Ensure the tractor is off and actuate the hydraulic levers to relieve any residual pressure in the system before uncoupling lines.

2. 2

   Disconnect Lines

   Carefully detach the supply pipes and hoses connected to the external remote valve.

3. 3

   Remove the Valve

   Unbolt the valve body from the hydraulic block/stack.

4. 4

   Disassembly

   Carefully disassemble the valve, taking pictures as you go to note the exact location of all components, springs, and spools.

5. 5

   Inspect and Reseal

   Minor issues and external leaks can often be repaired by replacing the internal O-rings and seals using a model-specific seal kit. Inspect the spool for scoring or wear.

6. 6

   Reassembly

   Reassemble the valve components in the exact reverse order.

7. 7

   Reinstall and Test

   Mount the valve back to the tractor, reconnect the hydraulic lines, top up the hydraulic fluid, and test the system for leaks and proper pressure.