Do me a favor, take the snap ring out of one of them lifters, and see if the spring is broke!
You need to double check you pre load..........................WHAT A MINUTE!
OK you say that the plunger is below the snap ring right!?
You need a new lifter before you can check the preload.
There is only .015" preload because the lifter is already half way down................The spring should be holding the plunger up agenced the snap ring.
Fallow what I'm saying?
I think the push rods are too long and broke the spring inside..........check it out!