I want to give some un-solicited advice to new engine owners on what to do, and what not to do, during break in. I am going to pre-face this by saying I have not received delivery of my engine yet and I have not broken one in.... However I have blueprinted and run-in high performance engines before, and I think I have a pretty good understanding of the Listeroid quirks. My advice comes as a result of some hard won experience.
To the rest of the group here, please feel free to chime in with advice, corrections, or to point out any omissions or add opinions. I am happy to discuss my reasoning here
To start with we are going to assume that your engine has been inspected, and is in fact clean and ready to run.
1) Do not use synthetic lubricants during break-in. Synthetics are great to run in a working engine that has settled in, but you will cause yourself unending headaches if you start out with a synthetic oil.
2) Do not use a high detergent oil during break-in.
3) Do not use multi-viscosity oil during break-in. My personal recommendation for breaking in a Listeroid would be to use straight non-detergent 30W or 40W and I would lean to the 40W during my own break-in.
4) It helps if the oil is pre-warmed for the initial startup (a small immersion heater in the crankcase could be used), and do not start up a dry engine... You should pre-lube everything. Get a pump oiler, put it in a crockpot with a couple inches of water; once hot shoot a squirt of hot oil into the tops of the cylinders, cam bearings, crank bearings, etc. while slowly turning over the flywheel. Be sure to manually prime the oil pump if so equipped, and shoot some oil on all external moving parts. Make sure the fuel rack is clean of paint or gum and put a drop of hot oil on all the linkage points.
5) It does not hurt to put an ounce or two of oil in the fuel tank.
6) It does not hurt to put a couple of strong magnets in the crankcase to collect metal filings.
7) Do not start an engine without water in the engine cooling jacket. People think that they can fire up a dry engine and run it for 2-3 minutes without overheating... This is a mistake. Most of these engines have "wet" cylinders, and hot spots can form nearly instantly... 2-3 minutes can result in damage without coolant. If you wanted to be really gentle on an engine, you would pre-heat the water as well as the oil.
Do not run a new engine, even for a short time, without a load. Diesel engines, especially new diesel engines, have to have a load on them in order to keep the rings from chattering. The pressure created when a load is applied and the rack is open is essential for seating the rings and ensuring that they stay seated and don't scuff and vibrate in the bore. This is especially important during break-in.
9) Don't grab the rack and race the engine up or otherwise permit it to overspeed... Instead, pile a load on it and gradually work the rack open to develop power... These are not racehorses.
10) After a few hours cumulative running with varying loads applied, drop the oil while the engine is hot, open the access panel and mop out the sump, clean the magnets. You can fine filter (2-5 micron) and burn your used engine oil so don't feel bad about making frequent oil changes during break-in... These engines have virtually no filtration system and unless you have modified things with the addition of a bypass filter system for the crankcase sump you will want to remove metal, water emulsion, and any sand frequently. Let used oil settle before filtering and mixing with fuel, and toss the bottom sludge.
11) I would consider the break-in period pretty much over after 100 hours under a load, but some of these pointers can be applied every time you start your engine.
Good Luck!!!