JCB 85Z-2 Mini Excavator

The JCB 85Z-2 Mini Excavator is a versatile and reliable machine; however, like any heavy equipment, it can experience issues over time. Below are some common problems associated with this excavator, along with possible causes and solutions:


1. Hydraulic System Issues

  • Problems:
    • Slow or unresponsive hydraulic movement.
    • Leaking hydraulic fluid.
    • Overheating of hydraulic fluid.
  • Causes:
    • Contaminated or low hydraulic oil.
    • Clogged filters or faulty seals.
    • Air in the hydraulic system.
  • Solutions:
    • Regularly check and maintain hydraulic fluid levels and quality.
    • Replace clogged filters and worn-out seals promptly.
    • Bleed the hydraulic system to remove air.

2. Engine Starting Problems

  • Problems:
    • Difficulty starting the engine.
    • Engine cranks but does not start.
  • Causes:
    • Battery issues (low charge or faulty connections).
    • Blocked fuel filters or air filters.
    • Faulty starter motor or ignition system.
  • Solutions:
    • Inspect and clean battery terminals, and charge or replace the battery if needed.
    • Replace fuel and air filters regularly.
    • Check the starter motor and ignition system for faults.

3. Track or Undercarriage Wear

  • Problems:
    • Uneven track wear or slipping.
    • Difficulty in manoeuvring.
  • Causes:
    • Misalignment of tracks.
    • Insufficient track tension.
  • Solutions:
    • Adjust track tension according to the manufacturer’s guidelines.
    • Regularly inspect and align tracks.
    • Replace worn-out tracks promptly.

4. Electrical System Malfunctions

  • Problems:
    • Non-functional controls or dashboard indicators.
    • Blown fuses or wiring issues.
  • Causes:
    • Corroded wiring connections.
    • Damaged or loose electrical components.
  • Solutions:
    • Inspect and repair corroded connections.
    • Replace blown fuses and damaged wiring.
    • Ensure all electrical components are properly secured.

5. Overheating Engine

  • Problems:
    • Engine overheating during operation.
  • Causes:
    • Low coolant levels.
    • Clogged radiator or cooling system.
    • Faulty thermostat or water pump.
  • Solutions:
    • Regularly check and top off coolant levels.
    • Clean the radiator and cooling system periodically.
    • Replace a faulty thermostat or water pump.

6. Boom or Arm Movement Problems

  • Problems:
    • Erratic or jerky movements.
    • Difficulty holding positions.
  • Causes:
    • Worn-out hydraulic cylinders or seals.
    • Insufficient hydraulic fluid pressure.
  • Solutions:
    • Replace damaged hydraulic cylinders or seals.
    • Inspect and maintain proper hydraulic pressure levels.

7. Fuel System Issues

  • Problems:
    • Loss of power or stalling during operation.
  • Causes:
    • Dirty fuel or clogged injectors.
    • Air in the fuel lines.
  • Solutions:
    • Use clean and high-quality fuel.
    • Clean or replace fuel injectors as needed.
    • Bleed air from the fuel system.

8. Cab Comfort and Control Problems

  • Problems:
    • AC or heater not functioning properly.
    • Unresponsive control levers or joystick.
  • Causes:
    • Faulty HVAC system components.
    • Damaged or worn control linkages.
  • Solutions:
    • Inspect and repair HVAC components.
    • Lubricate or replace control linkages if necessary.

Preventive Maintenance Tips

  1. Regular Inspections: Conduct daily checks on vital components, such as the hydraulic system, engine, tracks, and electrical wiring.
  2. Scheduled Servicing: Adhere to the manufacturer’s recommended maintenance schedule.
  3. Operator Training: Ensure operators are trained to use the machine correctly and report any issues promptly.
  4. Proper Storage: Store the excavator in a clean and dry environment to prevent corrosion and wear.

By addressing these issues early and maintaining a proactive approach to maintenance, the JCB 85Z-2 Mini Excavator can deliver optimal performance and longevity. For persistent problems, consult a professional technician- That’s us!

Spares & parts bibliography

For all spares and parts we recommend our sister company – HTS Spares

For all JCB excavator parts: JCB Style Excavator Spares | All products shown are quality replacement parts and are not genuine JCB products. 

Spoke to Jeremy at HTS Plant on Monday morning about a generator they had in stock agreed a deal, arrived onsite Tuesday lunchtime "excellent service" Hard to find likeminded honest genuine company’s these days HTS are spot on. Jeremy even took the time to phone making sure everything was ok.
Paul B, Developer in Asselby