I was in my truck today coming home and I go to crank the motor over and it takes about 8 seconds to fire up, and when i got home I smelled fuel somewhere, and I pop the hood and I see fuel all over the main wires by #6 piston, I go to fell all the injector connector lines and #3,4,5,6 have fuel all uder the lines like they are leaking,what do I have to replace? or what is going on?

 

Check all lines for tightness using an open-end wrench, if any one feels loose, tighten it up. Spec torque is 30 lbs so full force of the wrist on a 6" wrench is Ok, even a bit too little. Wipe out the fuel from the top of the head everywhere and start the truck, and watch if you get a leak at one of the injector connectors.
If you have a flare end wrench, use it; on cylinder 6, crow foot wrench is the best if you have it.

 

I had one of these fittings loose on mine. I thought the line was cracked at first.

 

on mine, #5 line cracked right where it ties into the head. just inside the nut. Quick replacement job, and all is well.

 

I had my #3 line crack at the injector pump. I hadn't noticed a hold down bracket had come loose and allowed the injector line to vibrate and break. Fairly easy to replace. One line cost $80 from Cummins. Hardest part was fishing the line out of the bundle and fabracate a replacement bracket. It does make a mess when they break and that VP pump shoots fuel all over the engine bay and on the ground. Lucky I was close to home when it happened. Good luck...let us know how you make out.

 

I cracked at leat 3 injector lines on my '99 over the years.

The hold down brackets rattled loose over time and were replaced yet lines kept breaking. Some of them are tricky to replace depending on the location.

 

On a side note dont use your hand to find the leak. Those are high pressure lines. they will spray fuel into your hand very easily and that could be bad

 

it looks like fuel is somehow getting thru the nut on the injector line and where it screws into the head.

 

DD, that is what mine was doing when #5 cracked.

spray it down with brakleen, dry it with compressed air, and make sure the nut is tight, then start the truck, and watch what happens. If the fuel comes from between the nut and the line, the line is hooped. If it comes from somewhere else, well, that might be a little tougher.

This is just my experience with these injector lines

 

Pull off your #3 line, make sure the seats are clean, pull the connector tube, inspect for any burrs or deformation, replace O-ring, re-install all of it and try it again. Fuel will come out of the line and run back along the head, so look where the puddle forms, not where it ends.