The Stovebolt Site Forums The Shop Area Engine Shop Old cam new lifters?

My 6 cyl. has a couple of hydraulic lifters that will not stay up while pushing down on the respective pushrods. This engine has about 60,000 miles on it. Hotrod L. could I just replace the 2 old ones with 2 new lifters. Sounds a little risky to me. I don't even see how the engine even runs as good as it does with this here issue? Yeah with the engine off valve cover off I can push down on # 3 pushrod and # 5 pushrod, all the others don't even move. Maybe its not in the lifters I don't know?

Yes, you can replace a couple of lifters pretty safely. Just do the 20 minute run-in at fast idle like you would do with a new cam/lifter installation. Stovebolt lifters seem to have a chronic problem with being unable to purge air out of the lifters, so you might also try putting a shallow groove in the ball-shaped bottom of the pushrod with a Dremel tool. I think there's a tech tip on that somewhere on the website. It's also possible to remove the lifters that are giving problems, take them apart, and do a thorough cleanup with spray carb cleaner and reinstall them. Just don't try to intermix parts- - - -dismantle and clean one lifter at a time.
Jerry

I'll give that a try, I just don't understand why the engine runs so dam good.You see, I posted an earlier thread about a pinging noise which I am still trying to find and found this here little problem. I'm about to try your little hot water in a 1 qt. wiskey bottle and dribble it in there. Thanks.....

Your oil pressure at the gallery may be borderline - enough to properly inflate those tappets at the power test time, but not enough to keep them up when the pressure drops at reduced RPM.

While your lifters may leak down when manually depressing they may be perfectly fine when operating in a running engine because they don't have to provide resistance to leak-down for an appreciable length of time to adequately open your valve and can pump up again before the next valve opening assuming you have good oil pressure. Id say if the wear pattern on both lifter and cam is good and the engine is quiet don't worry but would ask if you are pretty certain the pinging you hear is not actually a push rod (or two) rattling? Good luck in your problem solving...

Being able to collapse a lifter with just finger pressure on the rocker arm is NOT normal. Either clean and reassemble, or replace any lifter in that condition. While it's possible to make a lifter bleed down with a heavy, constant pressure against it, like with a pry bar, it should not be able to be compressed easily.
Jerry