new lifter ?

By soaking, the lifter plunger is basically stuck full up when you torque the rockers down. It can hang valves open if they dont bleed down under valve spring pressure.I'n many cases this doesnt happen. But the reality is, not having the lifter full of oil will never cause damage. Having it full might. Plus, the lifters are actually pressure fed before the bearings. So they will get oil immediately and they won't hang valves that way.