Air up the line with 10-15lbs of air.....Get some Dawn dishwashing liquid....thin it with a little water.....paint the solution onto every fitting and let it sit......You can find the smallest leak with this technique....I had a line I was testing and it had avery slow leak......It was the cap I bought from Home Depot just to test the line.....Made in China and porous.....leaked right thru the metal and this was not the first time for this issue with something from H-D
THANKS! for some reason I didn't think about increasing the air. I googled this problem and found that you shouldn't use teflon pipe dope in a union. Not sure if this is true but I cleaned out the union, used some non-teflon pipe dope, and really tightened it. I then jacked up the PSI to over 15lbs and coated the joints. A Tee hub had a very small leak and the union was still leaking a small amount so I tightened both as hard as I could using big plumbers wrenches and I am now good.
The lessons I learned doing my first LP gas line rough-in installation:
1) CSST is coslty but much simpler and easier than black pipe.
2) Stop by the plumbers supply and get good pipe dope and don't be shy with it (on the male threads only).
3) Use some big plumbers wrenches and tighten the joints harder than you think is necessary. I was straining at times.
4) The black pipe and fixtures made in China can be defective so don't rule that out.
5) If you have a slow leak, jack up the PSI (make sure your guage can handle it) and coat the joints with a thick slurry of dish detergent and water and watch for subtle foaming.
Thanks to all that replied and helped!!!
Keith