Hard Fuel Line Leak at Hydraulic Head

[Computerdoc08]

the #3 hard fuel line appears to be leaking at the hydraulic head. I've reviewed some TMs and there doesn't appear to be any rubber seal for the hard line within the head that could be leaking. Is there a rubber seal I could install to try and stop the leak or should I replace the hard line? Any tips / tricks to removing? Or just unscrew at the head and injector?

Thanks

 

[cattlerepairman]

I suggest to loosen and re-tighten (not over-tighten) the fuel line at the head. Also, wipe the head dry and check for cracks. That may be difficult if you still have the aluminium plate on top with the line numbers.

No tricks to loosening/removing the hard line. I suggest spraying the fittings with penetrating oil before moving them to help them slide on the line.

 

[Computerdoc08]

I suggest to loosen and re-tighten (not over-tighten) the fuel line at the head. Also, wipe the head dry and check for cracks. That may be difficult if you still have the aluminium plate on top with the line numbers.

No tricks to loosening/removing the hard line. I suggest spraying the fittings with penetrating oil before moving them to help them slide on the line.

Thanks, ill try that later. Ive never done this before, should I expect some fuel to spray out or is it not under much pressure until started?

 

[NY Tom]

Good luck. My head started leaking at #3 as well. Some say this can be a weak spot and develop a crack there. You won't be able to see the crack.

I tried changing the lines, putting on new ferrules, polishing carefully to be sure there were no scratches down in there. Nothing worked.

I have a spare head another member was kind enough to send me which I will install in the spring and hope for the best.

Try the above and hopefully your problem will go away. If not probably need to find a new head.

As for removing - #3 is easy to get to. If it is already wet it probably will come off nice and easy. I had no issues loosening the lines. I have had all the lines off and on and even replaced lines with good used and all the ferrules sealed up nice except for #3 at the head. So the system doesn't seem to be overly sensitive to scratches on the ferrules.

I had my head off because it was leaky and I figured it was the O-Rings - which were leaking. Cleaned everything nice and dry. Started truck and ran it afterwards no leaks and felt really good about it. Once the rest of my repairs were ready and I started driving the truck is when #3 started leaking. I bet it leaked all along but with so much diesel around I could not tell from where. Now it is obvious. Head won't leak at idle or even revved up with no load. Mine has to be under load when the fuel charge is really getting slammed in there hard. Then you will get the leaks so don't think you are OK if it is dry at idle or even running at 2000 RPM with no load.

 

[NY Tom]

I also pulled my #3 injector and replaced it thinking it might not be opening and with no where to go the fuel charge might be squeezing out somewhere. Well that was not the problem either in fact a good injector probably made it worse with the correct pop-off pressure being higher than a worn out injector.

Point being that even after having the #3 line off and on like 10 times it never leaked at the injector connection - so the design of the sealing seems to be insensitive to damage to the ferrules. Once I take the old head off I guess I will try to use crack penetrant to see if I can find the actual crack point.

 

[NY Tom]

A related post here.

 

[Menaces Nemesis]

It'll seem pretty obvious when you're doing it, but it's easier if you revove the lines from front (toward the L. fender) to back (toward the engine) and reinstall in reverse order. An 11/16 flare nut wrench can be very helpful to remove/install the line nuts without rounding them (I've got a dedicated one, just for this purpose, that I cut a bit shorter to get into tight spots). Once you get the line nuts off and pull the lines from the head, I'd suggest you remove that aluminum reference disc. It can mask a leak and make it a pain to tell where you have a leak at. leave it off when you reinstall, just put it somewhere for reference that it won't get lost. Carefully wipe the line ends, nuts, and bores in the head spotless clean before reinstalling.

 

[frank8003]

I don't remember any O-rings, just squashed metal meant to never leak no matter what.
This will lead you to the TM, better information there.

 

[Computerdoc08]

I've had an issue getting the proper #3 fuel line. I attached some pictures of the latest fuel line I ordered. The bends are not in the correct places (at least compared to whats currently on the truck). Am I supposed to do some bending on these or should they be a direct fit?

 

[NY Tom]

I tried to get a new #3 line from TNJ Murray and I received what you received. The fitting was correct but metric on the hex and the compression sleeve came loose when I installed it. Injector side fitting was correct. I think these are made overseas.

The bends were different I made an adapter or two to get them to attached to the mounts.

Because the sleeve was bad the line blew out from the hydraulic head end first time I test drove the truck and applied near full throttle. It is possible that I did not install it correctly and since it had a loose sleeve the line came up out of it and did not crimp properly. 50/50 I guess on that but for sure but the bends were not correct.

TNJ sent me no charge a good, used line to replace it. Bolts right in like the original. Did not solve my problem which was a leak at #3 BUT it was a good line. These lines seem pretty tough to me and seal over and over again in my experience if carefully removed and installed. Why did you replace yours?

 

[Computerdoc08]

My #3 line looks to be leaking up the tube at the hydraulic head. The protective covers arent there and there is rust in all of the recesses. The #3 leaks right in the small recess.

 

[NY Tom]

That's the problem I was having. Tried changing lines and even using a new sleeve. Still leaks.

Many say these heads crack at #3. Can see the crack by eye.

I have another head to try once it warms up and I have some more time. You may need a hydraulic head.