Bringing this back. As stated by the OP, there are a million discussions about this on various forums but I have yet to see a definitive answer. However it does seem the general consensus is that if they are solid and not compressible by hand they are good.
I currently have my engine apart for rebuild and these lifters are giving me a headache. I do not recall any lifter tick. I had 7 lifters that were uncompressable; #6 was able to be compressed by hand but would not pump up in oil. The lifters are all currently in 5w30 oil. I wanted to clean them so I used a syringe to remove the oil from #1, however it would still not compress afterwards. I assumed this was due to the check valve inside. (944 lifter opened -
youtu.be/ZCucAyf56Ik) I then placed it in a vice (in a towel) and very slowly compressed the piston slightly. The lifter now compresses smoothly although it will not get hard again when in oil. So now I have 2 lifters that will not become solid in oil.
Here are my questions on this:
1. Will the lifter not become stiff because the oil is too thick to flow through the 3 pin holes when not under pressure? Or did I somehow break the check valve in #1?
2. Could someone else discuss their lifter experiences. How do you remove the oil from the piston? Or other cleaning methods?
3. Has anyone used compressible by hand lifters with good results once installed?
Thanks!!