6.2 injector leaking at fuel line

[CWW]

My number 7 injector (last one on drivers side) was leaking when ever the truck sat for a few days and that bank would smoke when running cold. So I replaced the injector and now the connection between the injector and threads for the fuel line is leaking when the truck is running. I checked to make sure the rebuilt injector wasnt leaking. Just wondering if I need a new fuel line, or is there something I could do to stop the leak? Thanks for any input. The truck is a 1984 Chevy cucv K30.

[DmaxMaverick]

Whatever you do, DO NOT use a thread sealer, of any kind. The seal is metal to metal. Your fuel line may be out of alignment, the sealing surface could be damaged, the line could be cracked (usually right under were the nut meets the line), or there may be some debris interfering with the surface. If it is debris, the surfaces may now be damaged. They will usually clean up if they aren't too bad. You may need an inspection mirror, but you need to get a good look at the sealing surfaces. All this assuming you don't have an issue with corrosion. In which case, all bets are off, and the line(s) need to be replaced.

[Subzilla]

Make sure it's not as simple as the rubber return line leaking and squirting onto the metal line fitting. Sometimes looks can be decieving. I had my rubber end cap leaking last month and it appeared that the injector itself was leaking.

[CWW]

I checked the rubber fuel return lines, they are not leaking. I am going to see if the hard line is place properly in the injector.

[CWW]

I have tried to adjust the hard line to see if the line would stop leaking, but it is still leaking just as bad. I think the hard line is bad. Just wondering where is a good place to get another line? Also wondering if the intake maifold needs to come off to change the line? Thanks for any input.