The general conclusion is replace all "soft" lifters-if you can easily press in the "button"
You may want to fill the lifter with oil at the "air/bleed" hole on the side with a syringe and try again.
The lifters should be stored in oil with the side "air/bleed" hole UP.
A 10 percent solution of oil and SeaFoam is also suggested to loosen up the deposits inside.
Replace the lifters in the same bore they came out of.
New INA lifters have a reputation of failing----this may have been solved in the last few years. I do not know.
Good used "hard" INA lifters are suggested.
Information from posts. Quite a few in fact.
Britwrench is a master mechanic and very knowledgeable.
Question about lifters
What constitutes a BAD hydraulic tappet (lifter) ???? - Rennlist Discussion Forums
John