lets talk hydraulic lifter tech

[Fast68Chevy]

ok ive run into an enigne repair project for a friend in which cylinder #5 exhaust lifter flew out of its bore and the top end of pushrod got sheared off. as i was attempting to adjust all lifters a bit ago, i noticed that the plunger body inside the bodies of the lifters are not collapsing/traveling down in the bores, only a few of the lifters are acting correctly- same as the new lifter i soaked and installed ot replace the ejected one.

now, am i correct in saying that the lifters- that have plungers that wont give any at all and are stuck at top of their travel inside the main body of the lifters- have a problem?

i disassembled a couple of these that were jammed at top of travel and cleaned them out with carb cleaner and then reassembled them and now they work fine and travle up and down in there. i assume that that is how they are supposed to act unlike before i cleaned them and reassembled them. i told him to go ahead and get 15 more lifters and just replace them all and get it over with


who knows what on this subject ?