Thought you might have a truck engine with solids that needed
adjustment.
The hydraulics do get gummed up, they are very close tolerance,
just a few tenths clearance on the plungers. If your sure they
are getting oil and the galley isn't plugged up, you can pull
the lifter and dissasemble it to clean the varnish. What ever
you do don't use sandpaper or wire brush the them. A solvent
an fine (white) scotch bright will clean them. Also soaking
them in carburetor cleaner can help soften any varnish.
If you do end up disassembling the lifters to clean them, keep
them in order and on the same lobe and be VERY meticulous
about the reassembly. No pliers, no scratches and clean hands,
clean bench, clean lifter when you're dealing with parts have
that close of a fit. Compare this to the average human hair
which is .002"-.004" and you have some idea of how close a few
tenths is.
Denny Graham
Sandwich, IL
