Replacing a lazy lifter

They used to say soak them (submurged) over night or for a couple hours. That was then. Time has shown that not filling them with oil is a better thing for startup. The lifters get oil before the crank does with the mopar oiling system, so they pump up quickly in most cases, and it means when you tighten down the rockers the preload is properly applied. If you've ever tried to compress a hyd lifter in it's bore, especially an anti-pump-up deal, you'll understand why it's best to leave them empty until it's fully assembled and pre-oiled.