ShotPulled › Gear › Piston seal replacement
Fix a leaking piston seal, replacing it if needed: Cafelat Robot
Before you start
- Tools
- None listed
- Supplies
- Robot piston seal (red silicone, Cafelat; a consumable outside the warranty), optional; silicone grease (silicone-based, such as Dow 111 (Molykote 111))
Warnings
- Never brew with the red piston seal missing. Source: Cafelat Robot user manual 2.0, June 2020 (linked from cafelat.com/robot.html)
- Do not let the arms drop or press only one lever; use even force on both. Source: Cafelat Robot user manual 2.0, June 2020 (linked from cafelat.com/robot.html)
Steps
- Rule out overfilling first: leave roughly 5-8 mm between the water and the top of the basket.
From the manual: “Basket has been overfilled with water. Leave around 5-8mm gap”
- Re-seat the seal by running thumb and forefinger around it a few times until it looks even.
From the manual: “Silicone seal is not fitted correctly – ensure it looks even”
- Give the seal a little Dow 111.
From the manual: “Silicone seal could do with some Dow 111”
- Brew again with steady pre-infusion pressure and even force on both levers so the seal flares out.
From the manual: “The seal needs to flare out to form a seal”
- If it still leaks, fit a new piston seal (Cafelat rates this as unlikely to be needed). Only when: only if the leak persists
From the manual: “Silicone seal may need replacement (unlikely)”
- Seat the new seal evenly by running thumb and forefinger around it a few times. Only when: only if the leak persists
From the manual: “run your thumb and forefinger around a few times to seat it”
- Grease the new seal with Dow 111, just to a sheen. Only when: only if the leak persists
From the manual: “only to give the seal sheen”
Sources
Researched on .
Published: the sentence is on the maker’s own page or in the maker’s own document.