engine rebuilt, ways to transition

Rebuilt by whom? The warranty on the engine will probably have some specific requirements, so be sure to find those out from the rebuilder themselves. Also, there's really no such thing as "any generic engine". Different engines require different procedures, based upon whether the block or head is made of aluminum or iron. If you've rebuilt it yourself, the rebuild kit instructions might mention it.

Has the engine been run for the first time yet? Usually this involves setting the idle up around 1500RPM and letting it run with no load for an hour or so (depending). But this might be different for your engine. Usually you want to change the oil at the first 1000 miles, but check with the rebuilder/remanufacturer. They may insist that you have them change the oil (so they can inspect it).

Once again- take all this with a grain of salt, but get documentation from the rebuilder. They will have a very specific procedure for all of this, along with things like head bolt retorqing intervals, valve adjustments and the like, if necessary.

-phaeton

I, perhaps singularly, always recommend frequent oil changes.

At first, do not over stress the engine. Drive it for a few hundred miles near home and at reasonable speeds and accelerations just in case something wimps out on you.

After 200-500 miles, approximately, you can probably rest assured that the engine was put together reasonably, and that the likelihood for a sudden failure is decreasingly small.

Everything depends upon the quality of the machine work, parts, and rebuild technique. A rebuilt engine can be as good as, or better than, the original, but some arent.

Give it a calm and decent breakin, and take care of it .. I wish you well.

One thing I've always heard about rebuilds is to vary the speed and load applied to the engine for the first 3-5 hundred miles This is supposed to help the piston rings/newly honed cylinder get acquainted process. Also, just my $.02. When I used to rebuild Volkswagen and Corvair air cooled motors, I'd change the oil and filter after the 1 hour initial

2000 RPM run-in period, again at 50 miles, and again at 500 miles. Reason being, in that first hour, there's a lot of internal "machining" happening. Main and rod bearings, cam bearings, ring and cylinder wear patterns being established, etc. That all liberates metal (most of it very small) and puts it into the oil. I just felt better getting that floating around metal out of the engine asap. And time your run in. An hour of running at 2000 RPM seems like 10 when you're standing there waiting for it to pass.

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