Kubota U50-5 (5 Tonne) Excavator

The Kubota U50-5 (5-tonne excavator) is a reliable and popular machine, but like any heavy equipment, it can encounter specific issues over time. Below are common problems, their possible causes, and solutions:


1. Engine Problems

Symptoms:

  • Difficulty starting
  • Loss of power
  • Excessive smoke (white, black, or blue)

Causes:

  • Clogged fuel filters
  • Air filter blockage
  • Dirty injectors
  • Low-quality or contaminated fuel
  • Coolant issues (leading to overheating)

Solutions:

  • Replace or clean the fuel filter regularly.
  • Inspect and replace the air filter if necessary.
  • Clean or replace fuel injectors.
  • Use clean, high-quality fuel and drain the fuel tank if contamination is suspected.
  • Check the coolant level and ensure the radiator is clean and functional.

2. Hydraulic System Issues

Symptoms:

  • Slow or jerky movements
  • Loss of hydraulic power
  • Unusual noise from the hydraulic pump

Causes:

  • Low hydraulic oil level
  • Air in the hydraulic system
  • Contaminated hydraulic oil
  • Worn-out hydraulic pump or seals

Solutions:

  • Check and refill hydraulic oil to the recommended level.
  • Bleed the hydraulic system to remove air.
  • Regularly replace hydraulic oil and filters per manufacturer guidelines.
  • Inspect and repair/replace the hydraulic pump or seals as needed.

3. Track Problems

Symptoms:

  • Tracks slipping or coming off
  • Uneven wear
  • Difficulty steering

Causes:

  • Improper track tension
  • Worn or damaged track components
  • Misaligned track rollers

Solutions:

  • Adjust track tension to the recommended specification.
  • Inspect and replace worn-out or damaged track rollers and idlers.
  • Realign or repair track components as necessary.

4. Electrical Issues

Symptoms:

  • Faulty controls or dashboard lights
  • Difficulty starting
  • Non-responsive switches

Causes:

  • Battery issues or poor connections
  • Faulty wiring or corroded terminals
  • Damaged sensors or relays

Solutions:

  • Check the battery charge and clean terminals.
  • Inspect wiring for damage or corrosion and repair as needed.
  • Test and replace malfunctioning sensors or relays.

5. Overheating

Symptoms:

  • Engine temperature rising rapidly
  • Warning lights on the dashboard

Causes:

  • Blocked radiator or cooling system
  • Low coolant levels
  • Faulty thermostat or water pump

Solutions:

  • Clean the radiator and ensure there are no obstructions.
  • Check and refill coolant to the correct level.
  • Inspect and replace the thermostat or water pump if faulty.

6. Boom or Arm Malfunction

Symptoms:

  • Boom or arm not lifting/dropping smoothly
  • Weak digging power

Causes:

  • Hydraulic cylinder leaks
  • Faulty control valves
  • Worn-out pins or bushings

Solutions:

  • Inspect and repair or replace leaking hydraulic cylinders.
  • Clean or replace control valves.
  • Lubricate and replace worn pins and bushings as needed.

7. Fault Codes and Alarms

Symptoms:

  • Alarms sounding or fault codes displayed

Causes:

  • Sensor issues (e.g., temperature, oil pressure)
  • Software errors

Solutions:

  • Refer to the user manual for specific fault codes.
  • Inspect and replace faulty sensors.
  • Reset or update the software with the assistance of a Kubota technician.

8. Fuel System Leaks

Symptoms:

  • Fuel smell
  • Visible leaks under the machine

Causes:

  • Loose or damaged fuel lines
  • Worn seals or fittings

Solutions:

  • Inspect fuel lines and fittings for damage and tighten or replace them.
  • Replace worn seals.

Maintenance Tips to Avoid Problems:

  1. Perform regular maintenance as per the Kubota service schedule.
  2. Keep the machine clean and inspect it for wear and tear daily.
  3. Store the machine in a dry, sheltered area when not in use.
  4. Use only genuine Kubota parts for replacements.

If problems persist, it’s best to consult a qualified technician for expert assistance – That’s Us! 

Spares & parts bibliography

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

For all Kubota Parts: KUBOTA Spare parts | We have a considerable choice of KUBOTA Spare parts in stock available for next day delivery!

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