Is there anyway to tell the internal condition of a hydraulic lifter before you install it and run it? I have a externally nice set of used hydraulic roller rockers (no galling, concentric rollers) and would like to check out the internal condition before I put them in. If possible, does anyone know what I should be looking for?

 

if the outside looks good i run them. from what i understand the internals hardly ever fail it's mechanical wear on the exterior that fails most lifters for flat cams

 

Thanks, ede. These happen to be hydraulic roller lifters but you wouldn't have known that because in my original post, I called them roller "rockers". Mistake.

My concern is how can you tell if a lifter was sacked? Say you bought them used.

 

Pulling them apart is easy. I do it all the time.

Just use a pushrod and apply some pressure to the inners, pop the retainer out and use a small magnet to pull the inners out.

I clean them with good old mineral spirits, blow them dry, then throw them back together.

Once you're ready to install them, dump them in a container full of oil and let them sit overnight.

 

Thanks AJ_92RS. What am I looking for besides the obvious broken parts? How can I tell if the lifter is sacked?

 

As ede said (he's usually right), there's really nothing in there to break. The most that could break is the spring, but that's not likely. It doesn't do much except keep the plunger up when there's no oil in the lifter. I suppose it aids a little while the engine is running, but I can’t imagine a whole lot. It’s a very weak spring.

Every once in a while you'll hear someone talk about a “collapsed lifter”, but that’s usually a lifter that got enough crud in it that it seized and won’t compress. Of course with a flat tappet, the lifter usually wipes the lobe on the cam, then you have to replace the cam as well as the lifters (we all know to never use old lifters on a new flat lifter cam, right? ), so the lifter is said to be “junk” and never gets fixed.

I don’t mess with those at all. I only waste my time on hyd. roller lifters Once I have them back together, I push the plunger up and down a few times just to make sure it’s moving, and that’s it.

 

That's the answer I was looking for !! Thanks !