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This is the engine that was almost stuck. I had to take it apart. after a fair amount of work i had the engine turning free. I had it running several times for about a half hour each time.2 cylinders had no compression. I thought it was 1 intake and 1 exhaust valve sticking. i removed the valve cover thinking maybe the springs broke. I found valves are moving freely but 2 lifters take a fair amount of force to push down all the way and are holding the valves open slightly. the lifters look nice and shinney what could be causeing this? I thought if i ran the engine they would come loose but after an hour of total run time still not going the last 1/8 of an inch.

Are you sure if it is the lifter not returning fully or if the valve has crud on its stem and won't return? In either case, I'd say that, barring mechanical interference under the lifter or between the lifter and valve stem, that it's likely some crud - whatever was binding the works to begin with - has left a bit of residue on either or both sticking items. It could also be some residue inside the lifter, I suppose.


I'd try shooting some carb cleaner on each of the offending parts and then work them back and forth. It may take several applications. Maybe some acetone if it doesn't work. Be sure to change the oil afterwards as some of that mess will likely get into the pan somehow or another.


Barring that, sounds like there will be some disassembly, cleaning, and reassembly.


Good luck with it.


e/t/a: It could be bent valve stems, too. I had two of those on the last set of 356 valves that I removed. Hope not.

The lifter body is tight in the lifter bore. When i push down the lifter body the valve closes by itself. I have to use a pry bar to push it down

When a stuck valve is forced open by one of those hydraulic lifters the oil pressure within the barrel of the lifter skyrockets. That can cause them to permanently expand slightly and consequently jam in the bores.

You could try running the lifter up all the way and wrap a strip of 1000 grit paper around it and polish it down a tad.

Gee, that sounds like lotsa fun. I reckon that it beats tearing half the engine down - or a stick in the eye.