I am very curious as to HOW LONG people leave break-in oil in the engine, as while it is all good and fine to get the cam and lifters broken in properly, having anti-scuff additives in the oil will make it difficult, if not impossible, for new rings to bed in.
I have Brad Penn Break in oil 30 wt + ZDDP additive in mine right now, and have already run through the entire camshaft break-in procedure, as well as taking it out on the road a few times to seat the rings, only to realize that the rings aren't seating as well as they should, and am suspecting all the slippery stuff I assembled the engine with, plus the break in oil, plus the ZDDP, might be a bit much for the cylinders to get a chance to wear in properly.
Aircraft piston engines use straight mineral oil to seat the rings after an overhaul, or multi-weight ashless dispersant, but anything with an anti-scuff additive is avoided at all costs during break-in....and these engines have flat tappets. It sure gets the rings seated properly.
Should the break-in oil be tossed after the cam run-in? That would make sense to me....
Last edited by Norcal Dave; 03/01/2018 8:58 PM.
