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Old Cam, New Lifters?

Old Cam, New Lifters?

Old Cam, New Lifters?

(OP)
Greetings,

I know that it is advisable to install new lifters when you install a new cam.

Whats the current thinking on putting NEW lifters to an OLD cam?

Can someone expound on this?

Denis Kefallinos

RE: Old Cam, New Lifters?

I would think it rather rare that a tappett would fail alone without a similar failure on the cam lobe...
Having said that, I do have a set of Cosworth L-1 cams from the mid 60's that I recently installed in a Lotus Twincam engine for a vintage racecar.  Cosworth L-1's are rare but not all that uncommon.  This particular pair are, however, unusual in that I have used them in several different engines over the years...each time with NEW tappetts!
All I can say is, contrary to "common knowledge", the camshaft lobes are still "as new"(profiled for me by Isky Cams).
It is always advisable to use new lifters on any new camshaft as, in my experience, it's the lifter that wears in to the cam lobe and not the other way round.  I don't have all that much experience with pushrod engines, but intuitively, I don't see a big problem.  If there is, I am sure someone will point it out!

Rod

RE: Old Cam, New Lifters?

Shouldn't be a problem at all.  Troubles frequently start when the convex contact surface of a lifter gets flat.

RE: Old Cam, New Lifters?

I've installed used camshafts (American pushrod v8 and L6 engines) with new tappets on several occasions successfully.  The camshafts had proper wear patterns in all cases meaning nice and smooth across the nose and toward one side on the flanks like you would expect when running against convex tappets.  Also, the old tappets appeared to be in excellent condition in all cases but I pitched them and installed new.

That's been my experience anyway.

RE: Old Cam, New Lifters?

The opposite is the one that causes a problem- a new cam with used lifters. The lifters might contact at a point or might not rotate. Lifters usually pit before the camshaft, but once they start the wear rapidly increases and will take out the lobe. These comments are for flat lifters. I could be different for rollers.

RE: Old Cam, New Lifters?

Should be just fine. A great many OHC heads that have broken timing belts have had the lifters (and valves!) replaced, but kept the camshafts.

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