Fault Phenomenon: Hongda HBT100 pumps quietly when cold. After reaching operating temperature (high-pressure pumping), abnormal noise occurs, hydraulic lines vibrate severely, eventually leading to oil seepage.

Troubleshooting Process:
– Checked hydraulic pump coupling: worn elastic block replaced.
– Checked system cavitation: tank breather unobstructed.
– Checked pulsation damper pressure: damping effect normal when cold.
– Measured pulsation damper pressure at operating temperature: found damping effect fails.

Root Cause: The pulsation damper bladder ruptures, losing its cushioning effect.

Required Parts: Hydraulic pulsation damper assembly.