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I am still working on the 2.8 L chevy V6 I am going to start assembling her this week and want to know how I should brake the motor in. I here all kinds of stories and I know most all of these are wrong. How long is the brake in? How fast should the motor run? How long before my first oil change? I think I know but I want to be sure.
 

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I've heard of several engine break in theories, but only one on the cam; 2000-2500 RPM's for 30 minutes (and just get the thing to start & don't worry about timing it until you actually do the cam break in)... if I remember correctly it is critical to keep the oil pressure up for the cam break in and that is why the 2000-2500 RPM's - otherwise you'll ruin your cam.
 

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Ditto.
 

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I brake mine in very similar to solowookie, except every few minutes after start-up a move the idle up or down a few hundred bouncing between 2,000 and 2,500rpm. Then after about 20 minutes or so adjust idle, timing, and anything else needed. I usually on my own do the first oil change within the first 500 miles. Now here's the funny thing. We install reman engines in cars all the time at work. Mostly under warrenty still for bottom end noises,head gasket leaks, etc.. These are all fuel injected, no distributors or adjustments for the most part. We fire them up, run them long enough to burp the cooling system, then send them on there way. Not much of a fancy break-in but that's how we do every one. Do you really think a guy getting paid flat rate (by the job) is going to waste even 5 extra minutes getting that car out of his bay. Not in any dealership I've ever worked at.

[ April 01, 2002: Message edited by: dmorris1200 ]</p>
 

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I am assuming your cam is from a major manufacturer. Refer to their recommendations and follow them. They will include an assembly lubrication. Use it generously on the cam lobes and on the bearing surfaces. The thing to remember about the cam surface is that it is rough and must be "ground in" to the lifter surface. The cam lobe is splash oiled.....there is no directed spray for the cam, so it is oiled by oil slung away from the crank. If you have a windage tray, this makes things worse because there is less oil being splashed onto the cam lobe surface. So the breakin depends on the assembly lube and oil splash. You don't want to idle the engine for the first half hour or so, it needs to run fast enough to splash the cam. I won't recommend an rpm though I believe the 2500 to 3000 range is good. I repeat, read and follow the mfr.s recommendations. After you are done, you want to change the oil because it is going to contain all the slag, machine work filings, grinding slage etc. that you missed prior to assembly plus the residue from the cam and initial piston wiping.
 
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