Crane Roller Lifters OH NO!

[512Stroker]

Here are some pics. As those of you with vision will see, the two lobes on cylinder 4 are probably not going to buff out. Also, there is a crack on the intake lifter where it should be attached to the link bar, and the rivet holding it together is gone. Therefore the lifters were able to move sideways. Now it's just a matter of finding out what problem caused the other problems.

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First the lifter body cracked thru the rivet hole this then caused the rivet to fail.
The damage to the cam is collateral for the lifter rotating in their respective bores.
When I was a Engineering Lab Tech for an engine manufacture I found that the majority of failures came from the small parts, then those small part failures caused catastrophic damage.

 

[Mopar Sam]

First the lifter body cracked thru the rivet hole this then caused the rivet to fail.
The damage to the cam is collateral for the lifter rotating in their respective bores.
When I was a Engineering Lab Tech for an engine manufacture I found that the majority of failures came from the small parts, then those small part failures caused catastrophic damage.

Any thoughts as to why the body cracked?

 

[yellow rose]

I’m saying that’s a cam issue. Unless you have a bore with taper in it like PRH was saying, I think the cam had issues. Of course, a tapered or oversized lifter bore isn’t a lifter issue either.

Any little thing that causes the roller to skid or get loaded off perpendicular to the lobe will kill the lifter.

 

[Mopar Sam]

Well, I guess the next move is getting the motor out and apart. If the lifter bore is messed up, I have several LA and Magnum blocks, one of the magnum blocks already has the rocker oiling holes in the block.

 

[512Stroker]

I’m saying that’s a cam issue. Unless you have a bore with taper in it like PRH was saying, I think the cam had issues. Of course, a tapered or oversized lifter bore isn’t a lifter issue either.

Any little thing that causes the roller to skid or get loaded off perpendicular to the lobe will kill the lifter.

YR I hear ya
IMHO if the cam was the problem you would see similar damage on all the lobes.

 

[512Stroker]

Any thoughts as to why the body cracked?

I would take a real hard look at the valve springs for that hole and the pushrods.
Inspect the rocker arm tip to valve stem alignment.
It my be a combination of factors, kinda like the perfect storm.
Something loaded up that roller body that caused it to crack.
Nice pic's by the way, they always tell the real story.

 

[Mopar Sam]

I would take a real hard look at the valve springs for that hole and the pushrods.
Inspect the rocker arm tip to valve stem alignment.
It my be a combination of factors, kinda like the perfect storm.
Something loaded up that roller body that caused it to crack.
Nice pic's by the way, they always tell the real story.

We will give every thing a good look over.
Brian, badvaliant, took the pictures.
We will check the springs on the rimac.
I cut the pushrods to length when he went roller .095 wall. The rockers have one thread showing.
I haven't checked the others yet, but both of #4 pushrods are straight.

 

[512Stroker]

We will give every thing a good look over.
Brian, badvaliant, took the pictures.
We will check the springs on the rimac.
I cut the pushrods to length when he went roller .095 wall. The rockers have one thread showing.
I haven't checked the others yet, but both of #4 pushrods are straight.

Nice, check anything that loaded that cracked lifter body even the valve guide and valve stem. The lifter bore may tell you a lot.
Check all the other lifter bodies for cracks.
It may be the start of material fatigue or manufacturing issues.

 

[Mopar Sam]

I got the motor out and measured a few of the lifter bores. The one where the lifter body cracked is .0009 out of round, but very little taper. It measured .9055 parallel with the cam and 9.064 perpendicular to the cam. I measured a couple others and they were a couple tenths smaller, but also out of round. I was worn out, so I only measured a few.

I measured one of the good lifters and it was .9035
So I have about .0029 clearance in the thrust direction.

After Talking though PMs with a member, it is possible that the loose clearances caused the lifter to be out of plane enough with its paired lifter that it eventually caused the body to crack and fail.

We will save this block until I can obtain a Lifter Tru.
We will just start with another block, after thoroughly checking it of course. we have several blocks to choose from.

 

[512Stroker]

I got the motor out and measured a few of the lifter bores. The one where the lifter body cracked is .0009 out of round, but very little taper. It measured .9055 parallel with the cam and 9.064 perpendicular to the cam. I measured a couple others and they were a couple tenths smaller, but also out of round. I was worn out, so I only measured a few.

I measured one of the good lifters and it was .9035
So I have about .0029 clearance in the thrust direction.

After Talking though PMs with a member, it is possible that the loose clearances caused the lifter to be out of plane enough with its paired lifter that it eventually caused the body to crack and fail.

We will save this block until I can obtain a Lifter Tru.
We will just start with another block, after thoroughly checking it of course. we have several blocks to choose from.

Well there you go, nice detective work.
I wouldn't doubt that you find more lifter bores out of wack.
You know what it will take to fix it.
Good thing it did not destroy the whole engine.