Silicone oil is used to lubricate pistons only. It is not suitable to form the rigid seals on screw threads for eyedroppers.
Silicone oil is easier to work with compared to silicone grease as it does not leave a very greasy residue.
- If filling mechanism can be isolated safely, use a q-tip and apply modestly on the rubber rim of the piston.
- If filling mechanism can not be isolated safely or requires a special tool (Lamy 2000, Montblanc 146/149, Visconti power fillers) then apply a moderate amount on the inner wall of the pen. Then, operate the piston immediately to apply the grease onto the piston.