When sourcing a used block machine, the most critical technical factor is the hydraulic system integrity and the cycle time. You must verify the clamping force and vibration frequency, as these directly impact the density and strength of the produced blocks. Ensure the mold condition is checked for excessive wear; a worn mold will result in dimensionally inaccurate products. Additionally, confirm the PLC brand (e.g., Siemens or Omron) to ensure that software updates and replacement parts are globally accessible.