I'm in the process of putting a '99 4.6L v8 back together. I examined the lash adjusters from my original '98 engine and the '99 replacement engine I'm rebuilding and thought they didn't seem to be behaving the way I thought they were supposed to. They seemed completely frozen to me. No matter how I stuck a paperclip into the "pee hole" on the end I could not get them to bleed out. There were only a couple of them that I could get to depress about 1/32". So, I figured they were probably worn out. I ordered a new set of Enginetech L4600 lifters from RockAuto. They arrived today. I know that you are supposed to install them primed with oil, and in that situation they are extremely hard to depress. I figured I would try to bleed one out though, just to see how they are SUPPOSED to behave. To my surprise, they don't. No matter what size paper clip I stick in them, I can't get them to bleed out at all or depress. I'm not real keen on sticking them in a press just to see them depress, because with my luck I will destroy one.

Is this normal behavior for these things? I'm starting to wonder if my old lifters weren't bad at all ... or if perhaps the new ones themselves are bad ... sitting on a shelf for years or something.

Thanks,
Steve
Kissimmee, FL

 

The factory lash adjusters were ok. If the lash adjuster is collapsed and will not pump up then it is defective. Try inverting them and pressing them they will bleed down in that position. You just spent good money on new parts when the old ones were just fine. We have probably all done the same thing at some point....Live and learn.