Scotty,

I installed a reman engine ($4700) in a 2007 Xterra about two years ago.  Warranty is for three years.  Less than 18k miles in two years and one of the crank bearings spun out.  They were happy to send me a warranty engine at no charge, but before I installed it, I put it on a stand, filled it with oil, fogged the cams, lifters etc and put a little marvel mystery oil on top of the pistons, primed the engine via the oil pressure switch port and rotated the engine until I saw oil coming up the vvt ports. Then installed the vvt solenoids and performed a leak down test. Now I expected to have leakage on the pistons because the engine isn't hot, but at TDC for each cylinder, all exhaust and intake valve leak. I sprayed some fogging oil on top of the valves and can see bubble baths.  This is true for each cylinder.   I did not expect this, but need your opinion on whether some leakage is expected and I am being too picky.  I didn't expect to see any leaks.