This is THE stuff to use...
Thread Sealant
Speed Bleeder Thread Sealant
Used to replace the thread sealant that will eventually wear off if you bleeded your brakes frequently. It is mainly used by racers who bleed their brakes after every race. It comes in a 1/2 ounce bottle with an applicator brush built in to the cap.
http://www.racerpartswholesale.com/p...Speed_Bleeders