Engine: Break in Oil

[drnittler]

For a newly rebuilt engine, what is a good break in oil to seat rings, etc? Thanks.

[PackardV8]

Whatever is on sale at your FLAPS, because you should be changing it at 500 miles. Just don't use any synthetic or synthetic blend.

It really depends on how your block was honed. With today's best science honing, rings should seat quickly.

That's assuming you used standard or moly rings. The old tech chrome rings are another story. They can take a looong time to seat. That's why I don't use them any more.

jack vines

[JohnM15]

Any non-synthetic 30 weight oil with ZDDP additive and change after the first hour of run time. Start engine and keep it at 1500-2000 RPM for 20-30 minutes to break-in the cam/lifters.

[Mike Van Veghten]

There are MANY current/modern...breakin oils....just look within the internet..!

As Jack notes, one way to do this is to use a good quality standard oil (I like the old fashioned Valvoline Racing oil). Then add a bottle of Comp Cams or Lucas, or Edelbrock or Royal Purple, or Amsoil, or..............breakin oil.

Put about 50 miles on it....then change the oil AND the filter to the "same" oil and run it for about 400/500 miles, then swap to synthetic. I like Mobil I.

Why change it at 50 miles, to get rid of the assembly garbage and the initial iron particles coming off the cylinder walls, the rings, the cam, the lifters...the cleaner the better.

Mike

[drnittler]

Thanks one and all.