Clean the cylinders then squirt, it'll be fine. As for the lever I take the hose and grub screw out, poke the piston out of the lever body with a spoke (through the hole where the grub screw was) clean everything with water and a lot of kitchen towel. Then stretch the old spring, douse the 'plunger'/piston and lever in lubricant replace spring and poke in plunger. Reassemble lever with hose and blade then bleed. That's what I do anyway. Oh and I dont use anti-freeze with my water bleed (never really gets cold enough to freeze down here).