PC55 Main Relief Valve for Komatsu PC55MR-2, PC55MR-3, PC55MR-5 Excavators

   The PC55 Relief Valve is engineered to maintain the performance standards of Komatsu's most popular 5-ton class mini excavators. Given that the PC55MR series often works in tight urban environments with high-frequency cycling, the relief valve must be incredibly responsive. This cartridge-style valve is built to handle rapid pressure spikes, ensuring that the excavator maintains steady breakout force without "stalling" the engine or damaging the hydraulic circuit.

The SPARKLING MACHINERY NEW PC55 Relief Valve Photo:

Why Choose the SPARKLING PC55 Relief Valve?

• • • • • • • • • • • • • • • • • • • • • • • • •    - Multi-Generation Fit: Designed to meet the flow and pressure specifications across the Dash-2, Dash-3, and Dash-5 generations.

                                                •    - Shock Damping: Features internal damping to prevent "hydraulic hammer" effects when functions are suddenly stopped.

                                                •    - Corrosion-Resistant Coating: The exterior is treated to resist the harsh conditions found in the excavator's engine and valve compartments.

                                                •    - Factory-Calibrated: Arrives ready to install, though it allows for fine-tuning to meet specific attachment requirements (e.g., thumb or hammer circuits).

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                                          • Compatible Komatsu Models

                                            This valve is a direct fit for the following PC55 compact excavator models:

                                            Machine Model	Generation	Typical System Pressure
                                            PC55MR-2	Dash-2	Standard 24-27 MPa
                                            PC55MR-3	Dash-3	Standard 24-27 MPa
                                            PC55MR-5	Dash-5	Advanced Sensing Hydraulics

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Q&A Section

Q1: How do I know if my PC55 relief valve is failing?

A: If you notice a general loss of power (the machine "groans" but can't lift a full bucket), or if the hydraulic oil is getting excessively hot very quickly, the relief valve may be stuck open or its internal spring may have lost its tension.

Q2: Is the relief valve for the PC55MR-3 the same as the one for the PC55MR-5?

A: Generally, yes, as they share the same base hydraulic architecture. However, always check your specific serial number. Komatsu sometimes updates the valve internal seal kits or pressure settings between generations.

Q3: Can I clean the relief valve instead of replacing it?

A: If a piece of debris is stuck in the poppet, cleaning might solve the issue. However, if the internal seat is pitted or the spring is fatigued, the valve will continue to "leak" pressure internally, and only a full replacement will restore 100% power.

About SPARKLING MACHINERY:
   - Founded in 2013, SPARKLING focuses on high-quality excavator parts across hydraulics, undercarriage, engines and electrical systems. We prioritize stability, precision and continuous service, offering worldwide distribution, tailored solutions and strict QC to help customers reduce cost and increase uptime.

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