[Perfectlap]

best case scenario, sticky lifter. Ask the seller if he's tried draining the oil, cycling a thinner weight and using some Swepco type additive, dump that and fill up with some new oil at regular weight. That could possibly get rid of that racket almost entirely and kind of makes sense since the seller says it quiets down after the engine warms up. Old oil sometimes builds up and becomes sludgy/varnishy. A noisy lifter is often a lifter that's stuck on something. Either way, never, ever buy without a PPI that includes both a compression and leak down test. You need both. The seller should provide this otherwise buyers will be running away making it a waste of his time.