On the first start up, keep an eye on each joint you had apart. Sometimes the cone that the flared pipe seals to is worn enough, new line don't seat well and you really have to torque them down. Thats were some light grease or oil helps on and under the fitting, teflon tape also works in this case as a lubricant only on the threads. And remember the rules of teflon tape, never get it over the front edge of any thread because it always comes loose and gets stuck in the needle and seat!
Joe
