Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Diagnosing and Addressing Issues with the Hitachi EX200-1 Tobis TBP112DT Pump Loaded Condition
#1
Introduction: The Importance of the Hydraulic Pump in Hitachi EX200-1 Excavators
The Hitachi EX200-1 excavator relies heavily on its hydraulic system for effective operation, with the Tobis TBP112DT pump playing a crucial role in powering various hydraulic functions. When the pump is "loaded," meaning it is operating under excessive pressure or strain, operators may experience reduced performance, overheating, or mechanical wear. Understanding the causes and solutions for a loaded pump condition is essential for maintaining excavator reliability and efficiency.
Overview of the Tobis TBP112DT Hydraulic Pump
  • Pump Type: The TBP112DT is a variable displacement axial piston pump designed for high-pressure hydraulic applications.
  • Function: It supplies pressurized hydraulic fluid to the excavator’s cylinders, motors, and other hydraulic components.
  • Control: Variable displacement allows the pump to adjust flow rate based on demand, optimizing efficiency.
  • Load Condition: Occurs when the pump faces resistance or blockage in the system, causing high pressure and strain.
Symptoms of a Loaded Pump
  • Excessive engine load or RPM fluctuations.
  • Increased hydraulic oil temperature.
  • Decreased hydraulic performance or slow actuator response.
  • Audible whining or knocking noises from the pump.
  • Erratic boom or arm movements.
  • Potential activation of hydraulic pressure relief valves.
Common Causes of the Pump Loaded Condition
  • Blocked or restricted hydraulic lines: Dirt, debris, or damaged hoses limiting flow.
  • Faulty control valve: Malfunctioning valve restricting hydraulic fluid movement.
  • Excessive hydraulic system pressure: Overly tight relief valve settings or system blockages.
  • Worn or damaged pump components: Internal leakage or mechanical wear causing inefficiency.
  • Hydraulic oil contamination: Particulates causing valve sticking or pump damage.
  • Incorrect pump adjustment or calibration: Affecting displacement and pressure output.
Diagnostic Procedures
  • Visual inspection: Check hydraulic hoses, fittings, and valves for leaks, kinks, or damage.
  • Hydraulic pressure testing: Measure system pressure to identify blockages or valve faults.
  • Flow testing: Verify pump output against specifications.
  • Oil analysis: Assess contamination levels and oil condition.
  • Pump inspection: Check for signs of wear or damage internally.
  • Control valve function test: Ensure smooth operation and correct settings.
Repair and Maintenance Actions
  • Clean or replace clogged filters and flush contaminated oil.
  • Repair or replace damaged hoses and fittings.
  • Adjust hydraulic relief valves to manufacturer specifications.
  • Service or replace faulty control valves.
  • Overhaul or replace the TBP112DT pump if internal damage is severe.
  • Implement regular maintenance schedules to prevent contamination and wear.
Real-World Example
A maintenance team working on a Hitachi EX200-1 reported sluggish boom response and overheating hydraulic oil. After inspection, they found a partially clogged return line and a worn pump swash plate causing excessive load on the TBP112DT. Replacing the hoses, flushing the system, and rebuilding the pump resolved the issue. The operator noted smoother hydraulic function and improved machine responsiveness.
Technical Terms Explained
  • Variable displacement pump: A pump that can change the volume of fluid it moves per rotation to match system demand.
  • Swash plate: A component in axial piston pumps that controls piston stroke length, thereby adjusting flow.
  • Hydraulic relief valve: A safety valve that limits maximum system pressure to prevent damage.
  • Actuator: A device (such as a hydraulic cylinder or motor) that converts hydraulic energy into mechanical motion.
  • Hydraulic oil contamination: The presence of dirt, water, or metal particles in hydraulic fluid, causing wear and malfunctions.
Conclusion: Ensuring Optimal Performance of the Hitachi EX200-1 Hydraulic System
A loaded condition in the Tobis TBP112DT pump of the Hitachi EX200-1 can significantly impair machine function and risk component damage. Through thorough diagnostics, timely repairs, and diligent maintenance, operators can maintain hydraulic efficiency and extend the lifespan of their excavators. Awareness of symptoms and adherence to proper hydraulic system care are key to preventing costly downtime and ensuring safe, productive operation on the job site.
Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Troubleshooting Common Issues with the 420 Backhoe: A Comprehensive Guide MikePhua 0 1 36 minutes ago
Last Post: MikePhua
  Low Compression in Cylinders: Diagnosing and Fixing Issues on the John Deere 772GP MikePhua 0 1 40 minutes ago
Last Post: MikePhua
  Troubleshooting the Genie TMZ 50 Bi-Fuel: Issues with the Gas Side Powering Up MikePhua 0 3 49 minutes ago
Last Post: MikePhua
  Troubleshooting Recurring Issues with the Volvo L150E Wheel Loader: A Comprehensive Guide MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Troubleshooting Vibration Issues in CAT 312 Excavators MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Understanding and Troubleshooting the CAT D6C: Common Issues and Solutions MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Hydraulic Leak Issues on the Bobcat 753: Troubleshooting and Solutions MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Isuzu YH3XL Injector Pump Leaking at Output Lines: Causes, Solutions, and Maintenance Tips MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Troubleshooting Engine Starting Issues on the Volvo EW180B MikePhua 0 3 1 hour ago
Last Post: MikePhua
  Diagnosing and Fixing Misfire Issues in the John Deere 210LE MikePhua 0 5 1 hour ago
Last Post: MikePhua
  Troubleshooting Speedometer Issues in the 1990 Peterbilt MikePhua 0 5 1 hour ago
Last Post: MikePhua
  Troubleshooting Case 1840 Lift Cylinder Issues MikePhua 0 5 1 hour ago
Last Post: MikePhua
  Troubleshooting Stalling Issues in the Caterpillar 308 Excavator MikePhua 0 5 1 hour ago
Last Post: MikePhua
  Troubleshooting Starting Issues on a CAT D3B Dozer: A Detailed Guide MikePhua 0 5 1 hour ago
Last Post: MikePhua
  Troubleshooting Auxiliary Hydraulics Issues on a 1996 New Holland LX565 MikePhua 0 3 1 hour ago
Last Post: MikePhua

Forum Jump:


Users browsing this thread: