OM617 runs perfectly smooth, but exhaust smells more than usual
 

I know that these always smell like diesel exhaust when running. I'm not seeing any more smoke than usual. It smells more like charcoal lighter fluid. What would be the likely possible causes?

Id fill it up somewhere else and see if you got a bad fuel blend

To me, diesel smells completely different after it's combusted. What you could be smelling is some leaking diesel somewhere.

Air filter?

Agree with this. Lighter fluid (in my mind) more closely resembles unburnt fuel. You may have a fuel leak under the hood. Even small leaks can smell strong.

Has your crankcase oil level been dropping for no apparent reason?

Some past members have claimed if the little O-ring on the Fuel Supply Lift Pump goes out Oil small amounts of oil are sucked out of the fuel injection pump where it mixes with the Fuel.

Oil level hasn't been a problem. I'm wondering what the symptoms would be if my injectors aren't atomizing well.

Trust your judgement. Performance changes are often subtle but if it smells like unburned fuel it probably is. Check and adjust valve clearance then do it again, check and adjust injection begin delivery timing then do it again. Check your injector spray pattern and pop pressure. All that is pretty easy to learn with relatively little invested but time and hand cleaner. If any or all of that hasn’t been done in the last year or so you will be amazed at what a little regular maintenance will achieve. That is where I would start. If it’s tuned correctly, has clean fuel, oil, air, and still has a problem then I’d start chasing other gremlins.

How old is your air filter? That is a prime issue on unturned fuel issues.

What appeared to be the original Injector Nozzles were shot on my 84 300D were worn out after 195K+. The only obvious symptom I can remember is after about 10 minutes of driving and the engine was up to operating temp I had hot idle shaking. On start up there was a little grayish smoke till it warmed up a bit.

I have no recollection of any unusual orders.

On the other hand I managed to install they fuel injection pump on my volvo diesel with that impinging extremely retarded and got billowing white fuel smelling smoke out of the exhaust. The whiteness was caused by the unburned atomized fuel and the sunlight on it. If the injection pump timing is retarded enough the fuel won't burn as it should.

On the other hand your fuel spray is directed down at the Ball Pin inside of the Pre-combustion chamber. I believe that the Ball Pin heats up really fast and spraying down onto combustion temp Ball Pin must mask a lot of poor atomization issues.

I dumped some waste motor oil into the fuel tank of my Volvo diesel car that already had diesel fuel in it and it made the exhaust stink months after that only time I did it. I had more then one person walking in a parking lot stop me and tell me how bad it smelled.

Agree. Mine was like that when the soft return lines started to seep.

If in California, try "renewable diesel" from Propel or Union 76. Idles smoother without the smell of fossil diesel. Doesn't smell like french fries either, as raw bio-diesel does.