Rancilio Silvia Steam Wand/Valve Shaft O-ring
O-RING 6,07 X 1,78 EPDM 105, 36402001. Stock O.E.M. replacement part Rancilio Silvia Steam Wand/Valve Shaft O-ring. In the pre-2008 (Versions 1 and 2) Silvia, you will more than likely need two each of these for both the steam wand and/or valve. In the post-2008 (Version 3, 4 and 5) only two are needed for the steam valve, and they are not used in the wand.
Also used by Rancilio as a solenoid flange o-ring, as well as the Epoca (one group) group head flange.
As with any o-ring and moving parts, lubrication is highly recommended.
Went in easily and works well! Just make sure you're careful not to twist the inlet pipe when you remove the valve!
Great service from Dave at Espressoparts. He gave me clear direction about installing those misbehaving o-rings. Ms. Sylvia has never worked this well.
I think it likely that all steam wands with o-rings will eventually leak because rubber deteriorates, and heat likely accelerates the process. My V1 Silvia is 8 years old, and although I do not make many milk drinks, the steam wand started to leak small amounts on startup. Taking the steam assembly off and rebuilding it is not difficult, but requires good wrenches, a vise, and an illustrated guide such as one finds fairly easily on line. Apparently one cannot use just any o-ring which looks right, but need these OEM ones to get the perfect fit, 4 of them.