Bubbling around injector

[bvolks73]

One of my small return lines between the injectors was leaking yesterday and I noticed bubbles coming out between the injector and the head where the diesel was leaking down. Is that a bit of compression leaking by the heat shield?

[burn_your_money]

usually it is only the diesel boiling off. Replace the leaky line and go from there

[Doug]

Sometimes they do seem to leak a bit, maybe because the threads are stretched. Try some teflon tape on the injector threads carefully installing the injector so that the tape stays where it is supposed to stay. There are other thread sealants that resemble grease but I have not had any experience with them on the car engine. They are commonly used in industry to seal high pressure assemblies.

[fatmobile]

I've seen several reasons for leaks around the base of the injector.
 Once it was a piece of sand on the heat shield,... another time it was a knick on the heat shield,... another time it was a rough surface on the part of the head the heat shield sits on.
 I check all this real well before installing injectors now.
 I took a long bolt, thin enough to fit through a heat shield, shoved that bolt through a piece of emery cloth, then through the heat shield,... a nut on the back to hold the emery cloth against the heat shield, then I trimmed the emery cloth.
 This was a tool idea I got from Andrew and I use it to clean up the head surface that the heat shield sets on.
 If you haven't been playing with your injectors, I'm not sure why they would suddenly start to leak.... maybe the previous owner reused the heat shields.
 Thanks for posting this in the troubleshooting section.

[neimis]

I took a long bolt, thin enough to fit through a heat shield, shoved that bolt through a piece of emery cloth, then through the heat shield,... a nut on the back to hold the emery cloth against the heat shield, then I trimmed the emery cloth.
 This was a tool idea I got from Andrew and I use it to clean up the head surface that the heat shield sets on.

Do you do this with the head still on the block? I would really hate to have the loose abrasive particles from the emery cloth ending up inside my cylinders....! I don't think that would be too good...

[fatmobile]

The pieces are small enough that I'm not worried about it.
If you are worried about it, you could remove the head,... or try used emery cloth and wet it.
 Or maybe you can figure out another way to surface the seats without anything falling into the cylinders.