Link Bar Lifter Failure

[skinny z]

is it a weird pic or are there some witness marks on the buttons holding the link bars.I see shiny spots on the 2 on the far right?Tom

maybe oil droplets?Tom

Picture quality. There are no unusual markings anywhere. As I posted above, even the broken set has wear marks on the lifter body that look no different than the surviving sets.
I'll post additional pictures later.

[skinny z]

Hydraulic, plain bearings, not that it would matter?
Any wear on the other links look excessive?
That link is almost friction-less at low revs & wouldn't have mush stress at high revs from trying to rotate unless the lobe or roller or lifter bore is off.
How are those buttons retaining the link staked on?

Good luck.

Yes. The rivets are staked on. It's almost impossible to tell if the rivet let go, the link bar hole got wallowed out or a combination of the two.
Looking at the damaged lifters, one was obviously rotating as the lifter wheel now looks more like a ball bearing. The other is in much better condition. Still trashed though. Maybe once the link bar turns up in the oil pan, it may tell a story too.

Thanks.

[skinny z]

Hard to tell in the photo put it almost looks like the button under the link bar in the pic pulled out (not staked in proper) and the other button failed as the first button started to work its way out of the lifter . Dan

Kind of my thinking as well.

[skinny z]

Is it me, or do some of the marks on those buttons look like the lifters had been installed the wrong way?

And if so what could that type of loading done to the retention fit of those buttons?

Orientation of all of the lifters with the link bar lettering were all the same. One of those assembly details to pay attention to.
Some additional pictures with the parts on the bench might provide a better visual.

[skinny z]

Is it me, or do some of the marks on those buttons look like the lifters had been installed the wrong way?

And if so what could that type of loading done to the retention fit of those buttons?

I think it's just you. Those pics aren't high definition enough to make any sort of determination about what, caused the failure. You're just guessing going by crappy pics on the internet.

Yep.

[skinny z]

A few pictures to show similar wear on the damaged set and a working set.

IMG_20211005_102129049.jpg

All lifters have the same markings.

IMG_20211005_102524840.jpg

The rivet holes on the failed lifters don't appeared to be damaged. The black oxide is still intact. With the body of the lifter being tool steel and I imagine the rivet is not, it's understandable what the weak link is in that assembly.

IMG_20211005_103039320.jpg

The rivets look to have the peened over section snapped off.

There doesn't appear to be any indicator that the other rivets are at the point of failing although the joint does appear a little sloppy. Without a fresh set to compare too, I can't say how much movement is within spec.

[skinny z]

Why does everything look so dry in the lifter valley, did you spray it down?

Sorry mag. I misread your post. I thought you were commenting on the poor housekeeping.
It's dry (rather than dirty) because the engine hasn't been run in a while. The last start up was to turn the car around a couple of weeks ago.
The spray down with rust inhibitor came after.

[swampbuggy]

It does not matter who you buy from or how much you pay for it, if you run parts long enough they will fail. 35k miles on roller lifters is a Lot without a rebuild . Mark H.

[novadude]

It does not matter who you buy from or how much you pay for it, if you run parts long enough they will fail. 35k miles on roller lifters is a Lot without a rebuild . Mark H.

Really? This is the first I've heard about link-bar roller lifters having such a short lifespan.

[skinny z]

Interestingly, the surviving lifters look to be in good shape.

[dannobee]

Years ago, we saw the tie bars fail more frequently than we had hoped, so it's been a problem for years. If you notice, the oems rarely if ever use tie bars and normally use some version of flats machined on the lifter body and corresponding forks or plastic covers to keep the lifters from rotating. There must be something to that.

I've also seen lifters with a "rivet" installed in the lifter body that matched up with a groove machined in the lifter bore. If one was careful and machined the groove incomplete at the top and installed the lifters from the bottom, it would appear at first glance to be a mushroom style lifter when viewed from the intake valley side. (Not to say that anyone would blatantly misinterpret rules like that or anything) But I never saw that type of lifter fail.

[skinny z]

Years ago, we saw the tie bars fail more frequently than we had hoped, so it's been a problem for years.

That in itself says something.
But as I said, this is new to me (us). Then again, I've the highest accumulated mileage in our group.

[stealth]

WTF....???

Why are these all bitched up???

[skinny z]

WTF....???

Why are these all bitched up???

A photographic illusion. Here's the same set under different light.

IMG_20211006_191940874.jpg

As I mentioned, other than the black coating on the lifters worn from the lifter bores, all the other parts appear to be tip top. So much so, that even at 30k+ miles, I'm tempted to re-use them.
Why the one let go is still a mystery.