Pieces of steel in cylinder??

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Boy as tough as those cam bearings look you would have figured the cam journals would be toast too.

Bearings took the hit again, and boy did they.

And thank goodness!

What's the block lookin like now?
 
Boy as tough as those cam bearings look you would have figured the cam journals would be toast too.

Bearings took the hit again, and boy did they.

Originally I was going to reuse the cam, but since I have the motor completely apart, I’m going to replace just about everything. I’m still wondering what caused all this. Could it have been solely through overheating? Or is there another factor here?
 
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And thank goodness!

What's the block lookin like now?

I was anticipating replacing the core plugs, but they look pretty good to me.
 
Do all the cylinders look that good? That came out alright! I think you're gonna make chicken salad outta chicken ****!
 
Replace them, they are cheap, they rot from the back side, where you cannot see the rust.
Just sand the edge of the plug, and the block with 180 grit sandpaper, use permatex, and install with a large socket, they are easy to do.
Mancini Racing Brass Freeze Plug Kit
I agree, they are real easy to replace now. Not so much later.
 
Originally I was going to reuse the cam, but since I have the motor completely apart, I’m going to replace just about everything. I’m still wondering what caused all this. Could it have been solely through overheating? Or is there another factor here?

Here is my observation again,.

Just like the pistons bottoming out against the broken valve seat chunks in the combustion chamber. With the force going down to the crank bearings, rotational force and extream downward pressure smeared the aluminum alloy crank bearings at the crankshaft.

Now same thing with the cam bearings, the valves that were trying to open were bottoming out against the broken seat debris in the combustion chamber, so the force was traveling back down the pushrods back to the cam and the extream high pressure and rotational force smeared the bottom halfs out of the cam bearings. All the force here was pushing down on the cam bearings, so the bottom half took the hit.

Have seen worn out cam bearings before from normal wear, and they are wore out all the way around 360 degrees, not just big gouges out of the bottom half like you have here.
 
Replace them, they are cheap, they rot from the back side, where you cannot see the rust.
Just sand the edge of the plug, and the block with 180 grit sandpaper, use permatex, and install with a large socket, they are easy to do.
Mancini Racing Brass Freeze Plug Kit

You will be glad you replaced the frost plugs, especially the ones on the back side of the engine. They will start dripping after 45 years and that would really tick you off when everything is bolted together.

Pop the old frost plugs out and you get a chance to clean the rust scale out of the bottom of the water jacket with a heavy wire and small tipped vacuum cleaner. Now the new engine will cool better too.

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And krazykuda on here made an excellent article to make sure that all of the plugs are in place, I suggest you read it, because there are some hidden ones that can bite you on a rebuild.
 
Originally I was going to reuse the cam, but since I have the motor completely apart, I’m going to replace just about everything. I’m still wondering what caused all this. Could it have been solely through overheating? Or is there another factor here?

Yes good idea to replace the cam, the lobes on the old cam were put under undue force when the valves bottomed out. They will likely chew out any new lifters you put on top of them, even though they look OK at a glance.
 
And what would that be?
Just in case..... You had better check the the valve train to see if the valve retainers were hitting the tops of the valve guides. Any bent pushrods?

Was this extreme cam bearing wear only only a couple of the cam bearings, like 2 and 4, or on all of them?

Put them in order largest to smallest (front to back) and see if the wear is more on one end than the other. Probably not, but just chekcin'.....
 
This thread has gotten really huge, 5,000 views in a month.

Interesting . . good study of what happened to this engine.

Thanks everyone for contributing, very unique what happened to this engine failure and why.
 
the force was traveling back down the pushrods back to the cam and the extream high pressure and rotational force smeared the bottom halfs out of the cam bearings.

That would explain the bent pushrod.

And krazykuda on here made an excellent article to make sure that all of the plugs are in place, I suggest you read it, because there are some hidden ones that can bite you on a rebuild.

Thanks for the tip, I've been browsing the how-to section quite a bit the last few days. Lots of really great info there.

Just in case..... You had better check the the valve train to see if the valve retainers were hitting the tops of the valve guides. Any bent pushrods?

Was this extreme cam bearing wear only only a couple of the cam bearings, like 2 and 4, or on all of them?

Put them in order largest to smallest (front to back) and see if the wear is more on one end than the other. Probably not, but just chekcin'.....

One bent pushrod, I believe it was #7 exhaust (?). Obviously I'll be replacing all of them. The extreme wear was on the middle three bearings, and about the same on all three. The two on the ends looked worn, but nowhere close to the ones I took pictures of. The guy at the machine shop said it looked like I lost oil pressure, and I had a long conversation with a buddy of mine who's very knowledgeable and he agreed. He also advised all of the same you guys have been saying - freeze plugs, cam, everything. Especially since I have it apart and it's much easier now than after I put the engine back in (plus I'll have peace of mind knowing everything has been gone through and done right). Of course, this conversation was before I got on here this morning and read the comments, so don't think I'm second guessing you guys!

So, I'm adding an oil pump to the shopping list, and more overtime...
 
This thread has gotten really huge, 5,000 views in a month.

Interesting . . good study of what happened to this engine.

Thanks everyone for contributing, very unique what happened to this engine failure and why.

Absolutely, thanks a bunch everyone. I was a little nervous joining and asking what I thought might be stupid questions, but everyone here has been nothing but helpful.

Great forum :thumbsup:
 
Lack of oil [oil pressure] to the camshaft and crankshaft bearings.


This is correct too. But you don't always see a trough where the cam is getting smashed into the bearing like that unless something is just forcing the cam into the bearing.

Lack of oil will smear the bearing materiel pretty evenly (is evenly a word???) around.
 
Is that a stock or aftermarket cam

I honestly don’t know. I tried searching for info by the numbers stamped on it, but found nothing. I don’t have a degree wheel yet, so if I was to measure it I’d have to wait. I’m going with a new cam anyway.
 
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