Hoping someone here can shed some light on this problem.
I just completed the build on my stroker motor it’s a 440, 0.60 over bore, 4.15 stroke crank and new rotating assembly,cam, roller rocker valevetrain etc… no apparent assembly issues, engine was pre-lubed with Joe Gibbs break in oil and assembled with assembly lube on all bearings.
The engine fired right up and ran for 25 minutes at 2,000 – 2,5000 RPM to break in the cam before the valvetrain stared seizing.
Now it’s torn back down and we have a mystery.
The valve spring seat pressure was not out of line, the cam broke in well, but 4 out of the five cam bearings are toast. One spun and three are severely “wiped “ including the #4 cam bearing that feeds the heads. The mains and rods look great, so there was no lack of oil or pressure, the engine had 70 PSI from the get-go. Since the mains and cam bearings feed from the same source, there would not be any reason oil was not reaching the cam bearings. New cam bearings were installed as part of the block prep and the cam turned freely in the bearings prior to final assembly. You can still see the oil hole (although mostly wiped) on the 3 bearings still in the block from the feed hole under the mains, so the hole was lined up correctly.
Any ideas?