Quote:
Originally Posted by Jonsey
johnta/Quick-silver: I wondered if the lifters might be solid based on the way they were acting. I pulled one. Looks hydraulic to me (I can see the plunger/keeper inside). See pictures. I see what you are saying about the lifters pumping up. I have adjusted valves years ago on a running stock engine by sound as well. I guess I could do that here. Why do all demonstrations show adjusting the valves on an engine that's not even in the car? Those lifters haven't had a chance to pump up.
steve25: There never was a coolant leak. I think I made a false assumption on the head gasket being bad based on the two cylinders that had no compression being adjacent. If I had done a more through diagnosis, I wouldn't pulled the head in the first place.
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I have these exact lifters in my engine. On a 7/16-20 stud, they require right at 3/4 turn past zero lash per their instruction sheet.
Mine are noisy and in my quest to solve the noise, I've spoke with techs at lunati who mentioned that the lifters are cleaned/packaged with a water based solvent that doesn't pair well with oil and can cause sludge in the plunger. Their instruction sheets specifically state not to clean the lifters however and not to soak them in oil before installation, just dip them for lubrication and install.
My anecdotal guess here is that the engine was built, those lifters installed, and since you let the engine set for a couple years during restoration, a couple of the lifters developed sludge enough to make them act like a solid lifter. Your preload was hanging the valve open as a result.
Considering you can get compression on those cylinders by not applying pre-load, that's where I would start. Take the lifters from the two offending cylinders and see if you can depress the plungers by hand. There's 120 thousands of travel in those lifters so you can absolutely tell if you depress the plunger.
If they are solid or barely move at all, you know what you're up against. I would in that case, get some mineral spirits and disassemble and clean each lifter (all 16). Re-install and adjust the valves to zero lash +3/4 turn (I go another 1/8th on the set skrew after) and run your compression test again.