Carburetor shaft seals

[boeing7873]

Do carburator shafts have seals? I do not remember seeing anything non metal in the shaft ends. Thanks.
JC

[Hotzenplotz]

JC

My original carburetors were series 1 and had no seals.
I bought used series 2 carbs with identical throttle blocks, and there were seals on the shafts.
item 5 on the pic are the shaft seals part-Nr 7121085401


I refurbished both pairs last winter, and both got seals

[boeing7873]

Are these seals made of what material? Is it some kind of rubber or plastic? Do these fail often? Not really in the mood to remove the carbs again....

[Hotzenplotz]

I honestly have no idea what the seals are made of.
I cleaned the old ones in petrol, and they did not dissolve...
later I decided to replace all gaskets including these rings

No idea if they fail often i replaced them "just in case"