New engine breakin/idling

New engine break in has been discussed on here several times before, but I have a specific question.

I'm overthinking this, but I know you should let the engine warm up and cool down good, especially on the old diesels. I also hear that no prolonged idling periods for new engines. How are you supposed to warm up and cool down without idling?? Or are they more meaning, don't let the fresh engine sit and idle for hours and not talking about just 5-10 minutes or so.

Here was a good break in topic from a couple years ago.
http://www.allischalmers.com/forum/forum_posts.asp?TID=113470&title=breaking-in-an-engine

Edited by Allis dave - 07 Apr 2017 at 11:02am

to me,warm up would be fast idle (7-900rpm) til thermostat opens then go to work.Cool down is in reference to an engine that has been loaded (plowing say).Again a fast idle cool down would be appropriate.Will let all parts reach a more or less equal temp and then go to idle and shut down.If not been under load (cruising down road at full throttle) then nothing to cool.

No prolonged idling basically means...don't just run the engine for the sake of running it. A new engine should be warmed up for a minute or two, then worked under varying loads, without pushing it too much for the first 50 hour oil change. As stated, when it has been under load it should cool down at low idle for a couple more minutes before shutting down.

On the newer engines, like what ACdiesel already said, the emissions aren't designed for idling and will cause issues.  Some of what has happened on all newer engines (gas or diesel) is that the water jackets are made thinner and contain less coolant.  Thus by having the fewer gallons of coolant around the cylinders and cylinder head to heat, the new engines warm up a lot faster.

I agree with Mack,,,,, I've broken in several engines and I was always told to warm them up under partial load (say a gear lower) then just start working them, being careful NOT TO DOG them or LUG THEM under normal rpm's!