Hey guys, i finally have a night to work on my 454 and of course the first thing i try to do ends abruptly with a problem. I am trying to adjust the valves and while rotating the motor i realized the plungers in the lifters aren't even moving. I had two sets of the same lifters (long story short- bought a new set, they got rusted so i bought another set. Same prt.# and everything) the old ones i could take a push rod and push the plunger down, sure it took some muscle but it still went down. I tried it with the new ones- no such luck. I put ALL my weight (about 250 lbs. of it!) on the pushrod and the plunger didn't budge. Someone said thats how it's supposed to be so i installed them. Now, adjusting them, it has me worried. SHould they really be like that? Thanks guys!

maybe the new lifters are actually solids?

even if they're pre-filled you should be able to make one bleed down by pressing on the pushrod cup for awhile. What is the part number on the new box? are they name brand or generic white box?

They might also be solid lifters that the manufacturer put into the wrong box..

They are comp cams 812-16. They do look different then the first set i had but members here just said it was a newer style? Thanks