Elcarajillo Doram For anyone buying ‘O’ rings for E 61 mushroom these are the wrong size.
I bought these as spec and they are too thick, they become displaced as the mushroom is tightened= water leaking around the head.
Really sorry to hear they didn’t work for you. :(
I took the specs (3.53 mm thick with 18.64 mm inside diameter) from a few places, for example here, here and here. Maybe there is more than one standard and different mushrooms need different sized o-rings?
I just fitted one of these new ones to my mushroom to check. It does look slightly thicker than the green o-ring I had before, but the o-ring is flexible and stretches, and it seem to fit well (see pic below, the new black ring is 3.5mm on my calliper and the green is 3.3mm, but when I stretch it over the mushroom it becomes thinner). I started the machine, let it get to 3 bar and didn’t notice any leak. Where exactly would I see a leak if this doesn’t seal properly? I will check again tomorrow morning.
New black one:
Old green one:
