Breaking in an overhauled motor

What is the best way to break in a fresh overhaul. I have access to a dyno, and i have a D-282 706 that i need to break in and was just wondering what everyones ideas might be

Light to medium loads for 1 to 2 hours, with lots of variability from near idle to high idle. Then going to brief full load periods of 5 min or so, then medium speeds and loads for 10 minutes between peak loads for till you get to about 5 hours total time. Then I would use the tractor on real work, avoiding full tillage or grinder work for the next 10 hrs. I would then use it as I needed to. I like to change the oil after 25 hours or no more than 40 to make sure there are no floating grit in the system. Keep an eye on the pressures and temps. Jim

Put it to work, Just don't abuse it.

Jim,

Have you seen grit on a new rebuild?

Yes. When polishing components, finishing the cylinder walls. sliding in inserts in cam journals, are deposited or hidden away in nooks and crannies. When breaking in the rings, tiny sharp metallic fragments are worn off of both the cylinder walls, and the rings and pistons. These metal and ceramic items in the .5 to 5 micron range get flushed out by the break in operation. My choice is to change the oil and filter after 20 to 40 hrs. Jim

Good, I had to pull the pan on the MH44, and found some in there. The oil pump was missing a coupling so there was no oil pressure for about a minute.

It scared the crap out of me. I am glad to here it is normal.

I have always been told to work the engine for the first few hours to make sure the rings seat. My Dad had his 1020 overhauled back a dozen years or so and he just putted around on it like a loader tractor does. Sure enough, it uses more oil than gas since then.
I should have took it when he wasn't looking and put the tiller on it and hit the bean stubble for an hour or two. Oh well, it is what it is.

ya but, the micron's jim's talking about you can not see, so if you found grit in the oil pan that is not normal for a new rebuild.its probably just sloppy or careless work.

(quoted from post at 19:55:26 12/31/12) I have always been told to work the engine for the first few hours to make sure the rings seat. My Dad had his 1020 overhauled back a dozen years or so and he just putted around on it like a loader tractor does. Sure enough, it uses more oil than gas since then.
I should have took it when he wasn't looking and put the tiller on it and hit the bean stubble for an hour or two. Oh well, it is what it is.

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I have heard and seen the same thing.

One of the absolute MOST important things when beaking in a new engine is to change the engine speed as you work it. Running it up to a high idle and leaving it there will produce bad results, as the rings will NOT seat properly. One of the best workouts you can do is take it on a road trip, running through all gears and at various speeds. "Pulling" up some fair sized hills in 5th (or 4th depending upon your tractor.....or 3rd for that matter) is about the right amount of work. definately, do NOT lug it under a heavy load.

2ndly, as Jim and other have stated, an oil change and filter change after the first 20-30 hours of run AT OPERTATING TEMP is also very important.

Last item, do NOT work it hard until after the first 2 items above are completed. Even then, I would ease into the hard work over a 30-40 hours period. You don't have to baby it, but I surely wouldn't go plow 40 acres of virgin sod with it before the first 30-40 hours of run time.

as always, IMHO, and as some say "your mileage may vary"......

Taken from an older IH service manual for the D282 engine:

Start the engine and operate at approximately one half throttle until operating temperature is reached.

Stop the engine, retorque the cylinder head bolts and readjust the vlave lever clearance.

Attach tractor to a dynometer and operate at full throttle part load until the engine temperature has stabilized.

[u:487a8508a5]Caution:[/u:487a8508a5] New engines or newly overhauled engines must not be loaded enough to bring the engine speed below rated load speed except momentarily.

[u:487a8508a5]Important:[/u:487a8508a5] It is very desirable that the tractor engine be operated under load for the first few days of operation.

[u:487a8508a5]Never[/u:487a8508a5] operate the engine at no load for an extended period of time during break-in, however it is also important not to overload the engine during this period. The tractor operator should be instructed in this break-in procedure. Also caution the operator to follow instructions in the Operators Manual under maintenance for valve clearance adjustment on a new engine.

This is what a newer service manual has:

Ignorance is bliss.

Any fresh motor we had back in the day got put to work immediately.

No break in by today's standards.

Dad and Granddad worked the snot out of them with no problems.

I had my SH rebuilt about 4 years ago. Engine builder said just go use it, don't abuse it. No special break in.

Well Dean, no doubt many farmers and others over the years did exactly what you said. And the engines work. Break-in is mainly about seating the rings and also flushing out the assembly lube and and left over garbage from overhaul such as honing, turning, cleaning/boiling out etc. It is absolutely not going to cause instant failure to NOT break in an engine.

My Dad used to say, "There are many ways to do things and get a decent result. There are very few ways to do things and get a good lasting result". To that point, oil consumption and overall life of the engine will be effected by taking time to break in an engine. Required? No. Strongly suggested, Yes.

So, this is NOT an "in your face" commentary. It is more a respectful disagreement. Happy New year my friend.