I guess this belongs in here since you have to build the lines.

I recently built a line to go from my fuel filter to the fuel rail using Earl's fittings and stainless steel braided line. One of the ends was seemingly difficult to tighten when installing the hose end to the line, however the other end wasn't so bad. Maybe I did something wrong?

I tried to follow the instructions on ANplumbing.com. After assembly I pulled on the hose pretty damn hard to see if the hose ends were loose, definetly didn't budge so I assume they won't leak. Does anyone know a good way to test so I can be sure?

The only other way I could think of would to be start the car and let the pump prime the line and then check for leaks.

 

nobody ever done this before or what? come on.

 

Pegasus racing sells some -AN plugs with schrader valves on them in order to do low pressure bubble testing. I'm sure you could fab somthing up or find these caps elsewhere.

 

+1. You could make your own test pieces or just buy the testing kit which is nice to have. One time investment to make sure you dont leak whats most likely a flammable liquid on a hot engine

 

when you start the car cold set the base to like 80psi, you will know right away if that line is no good.

 

AN fittings are always tricky it seems. There's a couple little tricks to do though. The toughness you had threading them together is usually pretty normal. It shouldnt be REALLY hard to turn, but should have some tension on it. The one that went together easier probably was because you didnt have the hose pushed up into the red piece of the hose end far enough. It will more than likely work, but you usually want the hose to be just below the threads in the red piece..this makes them a BITCH sometimes to get started, but its the right way to do it. Also, never-size(nickel based preferably) is a MUST on al AN fittings. This is so overlooked by everyone, but it makes a world of difference...and when you take them apart for whatever reason, they wont be all marred up and you can actually use them on something else! haha.
Kyle

 

Earl's fittings sells a pressure testing kit. I believe they may be available seperately if you dont need the whole kit....$$$