Gasket and shower screen
What is in the group, and which gasket
Bezzera treats a worn group gasket as technician work: its manual says to call a specialised technician to replace "the seal under the cup", and its warranty excludes wear parts such as seals. The method in this job is a retailer's and an owner's, not Bezzera's.
The BZ group is not an E61: E61 gaskets and screens do not fit. From the top down: the group body, an O-ring, the bell (Bezzera's "coupling ring") held on by socket screws, the red gasket inside the bell, then the shower holder and screen, both held by one centre screw.
When: Bezzera gives no interval. Its signs are water round the portafilter, or a handle that locks further right than it used to. Fine Coffee Company changes the screen with the gasket.
Bell off, screen out
From SalesRista's BZ10 video and Whole Latte Love's BZ-group rebuild video, read from the pictures (no commentary was transcribed).
- Switch off, unplug and let the group go cold.
- Take out the portafilter and lift off the drip grate.
- Undo the socket screws holding the bell with a hex key, and lower the bell.
- Holding the bell, undo the M5 × 16 centre screw with a flat-blade screwdriver.
- Take off the shower screen and its holder.
- Pick the old gasket out of the bell.
New gasket, back together
The same videos, in reverse.
- Brush the gasket seat in the bell, and the holder, clean.
- Press the new gasket into the bell.
- Refit the holder and the screen, and do up the centre screw.
- Offer the bell up and tighten its screws evenly, a little at a time.
- Lock the empty portafilter in to check it seats.
- Plug in, heat up and watch for water round the portafilter on the first shot.
A centre screw that will not turn: Fine Coffee Company folds the old screen to get pliers on the screw head, unscrews it, and fits a new screen.