How to make your Diesel last a long time.

[Duckhead]

Relatively new here so I hope nobody minds if I chirp in. While looking over some of the posts I noticed quite a few questions on the expected longevity of diesel engines. While I don't claim to be the lord-of-diesel... many useful points have been picked up as a diesel mechanic in another life.
Do as you want with these suggestions, this is from personal experience and various diesel courses from different manufacturers.

Synthetic Oil - doesn't need to be said does it? Use synthetic, not a blend (there are 5 grades). In the US, the oil companies got the labeling changed so they could add as little as one drop of synthetic to their Dino oil and put synthetic or synthetic blend on the label. The container must say "fully" or to that effect synthetic. Oil change intervals can usually go beyond what the oil companies state, use the engine makers oil change recommendation.

Don't idle a diesel engine for long periods. Of course you must give it a chance to warm up the piston(s). Diesels were made to work, when they loaf the rings don't fully seal causing cylinder glazing and excessive blow-by diluting the oil.
Idling causes undue wear on the connecting rod bearings (refered to as the lower end).

If the engine is not working, instead of idle have it rev at approx 1/3 of redline.

When working your diesel rev it up, again this can hurt the bottom end if it's run too slow.

Spinning big alternators is "work" don't do this at or barely above idle.

The color of exhaust smoke generated by diesels is very indicative of it's health... learn to recognize the teltale signs (white vs. dark) there is many sources of info on this online. For instance leaky injectors have a certain color, vs. bad rings etc.

As we all know it's the high compression that makes diesels what they are. High torque, fuel economy, clean burning - most of what comes out the exhaust is pure soot (harmless carbon), hardly any monoxides and tiny amounts of hydrocarbon.

What to watchout for - Diesels, because of their compression have a very low exhaust temp. On some truck engines the exhaust manifolds are a light-weight tin stamping and the paint doesn't even burn off. Try that on a gas engine. So if you suspect a high exaust temp, (yes it's hard to tell with water in there) something is wrong with compression

Cheers Duckhead