D7 17a fuel injector leak

Any ideas on this???
My 17a has developed a leak where the fuel line attaches to the injector on top of the head. First I tried to just tighten evrything up but nothing was really loose, so no help there. Then I took fuel line off-and injector hold down pipe-and injector out of the precup. Gaskets looked bad so replaced them, which did not help. After studying I determined the gaskets do not really seal up fuel only keep dirt out. Looking at the fuel line swaged end I noticed what looked like smashed down pieces of grease (or something). OK that must be where it is not sealing, cleaned up with fine emery- still no seal. Went to injector repair company and had 1/2" cut off and re made the swage. Still not sealing although a little better. If I try to tighten any more something is going to break. It did hold for a bit but after engine warms up gets worse again. Looks like it is leaking around the nut for the fuel line and also the pipe hold down for the injector. Any ideas or tricks????

The ends of the injector lines are not swaged. There is a ferrule fitting used. These ferrules have been known to split, requiring replacement of the line. In my opinion, those folks that like to bleed lines using the nut instead of the injection pump bleeders are more inclined to have this problem.

You will probably, if it is the capsule type injector, find that the hold down nut has been overtightened sometime and squashed the capsule, the fuel now leaks through between the holder and capsule then back up inside the nut, it is also possible that there is a hairline crack in the threaded area of the holder. Check that the top nut does not go right on to the chamber. you could also swap the injector with another to se if you move the leak. Whichever way you go, a new injector line with the correct ferrule on it is needed, they do wear with the pulses through the fuel lines.