Where is the leak?
Take a spray bottle and mix it with 4 parts water and 1 part liquid soap. Put pressure on the line and spray the mix on it. If it's leaking even a tiny bit, you'll be able to see the solution bubble. It's saved me a lot of time and headaches. Just make sure the line has pressure on it and you clean it aftewards so no soap or water gets in the line.
Dave


