No carbon?

[JeepSJ]

As part of my overhaul I am getting my injectors redone. After I pulled them I used a light to check inside each of the pre-chambers for cracked cups, etc... As I would expect, each of the chambers had a light coating of carbon/soot. Except for #1. It was bright shiny clean. The tip of the injector had a bit of carbon on it, but that was all. Could that injector have been leaking and just cleaned out the pre-chamber, or is it more likely that #1 wasn't firing at all?

[AKMark]

Many years ago on the farm my uncle and I were gonna tear down a big diesel in a farm truck and overhaul it during the winter. It was running okay, but not great, compression was all over the place but no cylinder was dead.

The last time it ran before we pulled it, he slowly and very carefully poured water in the intake while it was running. He did this VERY slowly, and you could hear the motor cough and complain, but he ensured he didn't stall it. I forget how much water he put in altogether, but it was not a small amount.

Two days later the motor was out of the truck, and when we pulled the heads I was amazed to find the piston tops were clean and shiny, the cylinder walls were clean, the heads and even the valves were clean.

I've tried it on a few gas powered vehicles prior to pulling them apart, and while I didn't use nearly the same amount of water as he did, I've seen similar results.

Don't know about why one would be different than the rest unless that injector wasn't working, but you may want to verify that the line feeding the injector isn't clogged.

[More Power]

As part of my overhaul I am getting my injectors redone. After I pulled them I used a light to check inside each of the pre-chambers for cracked cups, etc... As I would expect, each of the chambers had a light coating of carbon/soot. Except for #1. It was bright shiny clean. The tip of the injector had a bit of carbon on it, but that was all. Could that injector have been leaking and just cleaned out the pre-chamber, or is it more likely that #1 wasn't firing at all?

A hot running cylinder will sorta do that too, in that the combustion areas (piston crowns, head deck, precups, etc.) will appear clean or a light grey instead of black/sooty. Jim

[JeepSJ]

A hot running cylinder will sorta do that too, in that the combustion areas (piston crowns, head deck, precups, etc.) will appear clean or a light grey instead of black/sooty. Jim

Hot running as if too much fuel? Or too lean?