Master cylinder leak

[Glennster]

 I've got a new master cylinder and new lines going into it.....but the one in the rear leaks. I've tightened it to the point that I know I should not go any tighter. Is it a good idea to use teflon tape on the threads? Is there something else I should use on those threads?
THANKS!!!

[Moparal]

I am quite sure that you should never use any type of sealant from what I've read. Sounds like either the tube is bent a little not giving a full seat, or the dbl flare has a small crack in the bend

[hemiken]

  with Alan, i would be looking hard at the flare to see if it has been made correctly, if not it is a simple case of cutting off the flare and flaring a new end,  that is of course if you have a double flaring tool or access to one.

[Chryco Psycho]

as said above the threads have Nothing to do with sealing the line so the tubing must be damaged , you may need to replace or just re-flare the end of the line