I thought it was running a little rough...

If you saw my other post about recommendations for selling a non-runner then this will make more sense.

I went through a series of what started as starting problems linked to fueling, went through an inline pump, high pressure pump and new injector before it seemed to be sorted. Then on the way back down the A1 a few weeks later this happened. Needless to say I'm not spending anymore money on an expensive repair or new engine. This is actually the second engine after the crank snapped on the first

Shows what damage poor injectors can cause

wow, that looks very sad!

I'm surprised it was running at all with that amount of crap in it.

freelance said:

Shows what damage poor injectors can cause

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The injectors had been checked prior to this and one was replaced for new, although that was through a garage I wouldn't revisit if it was the only one in a 100 mile radius. This was possibly a long term overheating problem but the garage I trust's view was that given this was cylinder close to the turbo, there was an issue there. In any case further investigation and repair really wasn't worth the effort.

That's been dragging the wall for a long time, impressive that there's a delamination effect going on just above the rings.

Were the thrust bearings in place on the big end or were they missing?

Looks like it's just gradually been dissolved, melted away in places. Ugh, nasty!

That piston has melted above the top ring. This is where the piston is most valuable to high cylinder temps. This it due to its small intersection with the rest of crown.
On a diesel, this damage is often cause by over fuelling on that cylinder. Most likely because of a faulty injector.
It's possible that this was a caused by a past issue that has subsequently been rectified.
If the fault was fixed , an engine can run for many thousands of miles like that.

It would have an unusual combustion knock tho

freelance said:

It would have an unusual combustion knock tho

Click to expand...

I would have thought that it would run a bit rough, particularly at idle.
The second ring has obviously been sealing, so the engine will be running on this cylinder, just not as well as the other 3!