help with new lifters tbi 5.7

[eran tomer]

I bought a set of new GM lifters. some of them slid down part of the way and stopped, I had to press on them and they rubbed the bore although I used the GM break in oil. After a week or so (without running the engine) I tried to get them out with a magnet so they come out maybe a 0.25 inch out of the bore and get stuck.

 

[Schurkey]

That can't be good.

Is this a block that's recently been in service? No rust in the lifter bores? Hasn't been to a machine shop and cleaned via a shot-blasting cabinet?

Possible counterfeit lifters? Not made properly?

This is a TBI, so flat-tappet, not roller lifters...right?

 

[eran tomer]

Flat tappet yes.
Block wasn’t touched.

 

[packer0440]

I just tore down a TBI 454 recently and had a similar experience. Lifters would come out a little bit, but had to grab them with vise grips and spin a bit to get them out. Motor had 300k and they looked brand new, so it obviously wasn’t causing an issue. But I’m no expert on this by any measure, so maybe others can share their knowledge.

 

[Schurkey]

OLD lifters that won't pull up, can either be stuck with varnish (no big deal, solvent removes the varnish and they pull up easily) or they can have severely worn bottoms that have been "mushroomed" at the lower edge due to being "wiped" by the cam lobe.

No amount of solvent will remove the deformed metal at the bottom.

The steel of the lifter will tear-up the iron lifter bore as the mushroomed metal scores the bore when you force the lifter "up".

Better to remove the cam, and push a deformed lifter "down" to remove it from the lifter bore.

But none of that applies to Eran, since he's putting in new, not worn, lifters.