Grouphead Maintenance

LUCCA Tempo: Checking the Dispersion Plate Orientation

If you are experiencing difficulty locking your portafilter into place, and the issue persists across different portafilter styles and types of basket, your dispersion plate may be installed upside down. Here's how to inspect the dispersion plate.

Tools required:

  • 3mm Allen key

    Be sure to use a true metric Allen wrench (aka hex key) - "Standard" (English) fractional wrenches will look similar, but may strip the screw in your grouphead! This will make it extremely difficult to remove. If you look closely, the size and unit will be indicated on the side of the wrench.

    IMG_20250723_151008846


Before continuing ensure the machine is switched off and the grouphead is cool to the touch.

  1. Using the 3mm Allen key, remove the dispersion plate and screen from your machine.


    NOTE: It is very important to use the correct size 3mm metric Allen key - SAE hex keys (aka Standard or English) may look the same, but are slightly smaller. This can result in stripping the screw head. If in doubt, STOP!

    tempo_dispersion_plate_removal
  2. Next, verify the orientation of the dispersion screen (left) and dispersion plate (right). These should be assembled such that the dispersion screen fits nicely within the beveled edge.
    tempo_dispersion_plate_assembly
    tempo_dispersion_plate_correct
    tempo_dispersion_plate_incorrect
  3. Reassemble the grouphead, taking care that the small red o-ring remains in the upper groove underneath the dispersion plate:
    tempo_dispersion_plate_gasket_annotated


See also: