Hydraulic breakers are the “trailblazers" of harsh working environments such as mining, road construction, and building demolition. However, when your breaker experiences weak impact or low efficiency, it can seriously hinder project progress and may signal underlying equipment problems. In this article, we’ll systematically analyze the common causes of weak impact in hydraulic breakers and provide a clear, practical troubleshooting guide to help you quickly identify and resolve issues, restoring your equipment to peak performance.

If you notice any of the following signs, your hydraulic breaker may be suffering from weak impact:

• Significant drop in impact force: The breaker feels “soft" and cannot effectively break through material, leaving only shallow marks.
• Slower working rhythm: Noticeably lower blow frequency and longer operation cycles.
• Abnormal energy consumption: Increased fuel or oil consumption without proportional work output.
• Unusual noise or overheating: The breaker produces abnormal sounds or the hydraulic system overheats during operation.

When troubleshooting, always follow the principle of “from outside to inside, from simple to complex."

a. Excavator Main Pump Pressure & Flow Insufficient

• Reason: The breaker relies entirely on the carrier’s (excavator’s) hydraulic system. If the oil pressure and flow are below rated requirements, the breaker will lack power.
• How to check:
  • Ensure the excavator is switched to the breaker work mode (with dedicated PTO function if available). Standard digging modes typically don’t provide enough flow/pressure.
  • Use a hydraulic tester to measure the breaker’s operating pressure and flow, comparing with the breaker’s specification.
  • Check if the excavator’s main pump is degraded or faulty.

b. Hydraulic Oil Circuit Issues

• Reason: Hydraulic oil is the “blood" transmitting power—its condition is critical.
• How to check:
  • Oil level & quality: Check for adequate, clean oil. Replace oil if contaminated, emulsified, or degraded.
  • Oil temperature: Excessive heat reduces viscosity, increases internal leakage, and reduces efficiency. Ensure coolers are functioning.
  • Filter elements: Check if return filters are clogged. If the bypass valve is always open, contaminants may enter the system.
  • Hoses: Inspect for pinched, blocked, or delaminated hoses causing flow restrictions.

c. Tool (Chisel) and Lubrication Issues

• Reason: The chisel is the final link in energy transfer—its condition directly affects efficiency.
• How to check:
  • Chisel wear: Replace if diameter is below 90% of the original size.
  • Chisel jamming: Excessive clearance between the chisel and bushing wastes impact energy.
  • Lubrication: Ensure automatic lubricators work properly, or manually add grease on schedule. Poor lubrication leads to excessive wear and increased resistance.

a. Incorrect Nitrogen Pressure (Very Common!)

• Reason: Nitrogen in the accumulator stores and releases energy, pushing the piston back. Too little or too much pressure disrupts impact rhythm and reduces force.
• How to check:
  • Before testing, always release hydraulic pressure and position the breaker vertically.
  • Use a dedicated nitrogen gauge (never a hydraulic gauge) to test pressure, following the specification (usually 1.4–1.6 MPa).
  • If pressure is low, refill with high-purity nitrogen (≥99.5%). Never use oxygen or compressed air due to explosion risk.

If all the above checks pass but the problem persists, internal inspection is necessary. We recommend contacting authorized service engineers.

a. Control Valve (Distributor) Failure

• Reason: The control valve directs hydraulic oil. Worn or stuck spools due to contamination cause erratic or weak operation.
• How to check: Disassemble and inspect for scratches or sticking, and clean all oil passages.

b. Piston and Cylinder Scoring

• Reason: The piston and cylinder are the heart of the breaker. Scoring from contamination leads to serious internal leakage and loss of pressure.
• How to check: Disassemble the cylinder and inspect for longitudinal scratches, replacing damaged parts if needed.

c. Seal Failure

• Reason: Worn or damaged seals cause oil and nitrogen cross-contamination, resulting in foaming, abnormal nitrogen pressure changes, or external/internal leaks.
• How to check: After disassembly, carefully inspect all seals and replace as a set if aging or damage is found.

For fast diagnosis, follow this sequence:

1. Check excavator hydraulic performance and settings.
2. Inspect oil level, quality, temperature, and filters.
3. Examine the chisel and lubrication system.
4. Test nitrogen pressure.
5. If needed, proceed to internal inspection and seek professional service.

• Regular Maintenance: Replace hydraulic oil and filters at recommended intervals.
• Correct Operation: Avoid dry firing and off-center blows. Pre-warm equipment before use.
• Maintain Nitrogen Pressure: Check nitrogen every 150–200 working hours or monthly.
• Daily Checks: Inspect chisel, lubrication levels, and hydraulic hoses for leaks before starting work.

When your hydraulic breaker suffers from weak impact or low efficiency, calm, systematic troubleshooting is key. Most issues can be resolved by checking external power, oil condition, and nitrogen pressure. For complex internal repairs, always contact authorized professionals to ensure quality and avoid further damage.

We hope this guide helps you quickly restore your equipment’s performance and maximize your investment return.
For technical support or spare parts, please contact us anytime!