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Discussion Starter #1 (Edited)
Had a knock when hot, and only when hot. Pulled the engine and dug into it and didn't find anything that screams "bad bearing", but I did see that the center mains were polished to a mirror like shine. The crank journals were all perfect. Zero defects whatsoever. What do you all think?

Rearmost cap has some weird horizontal scars.


Cap 2:


Cap 3:


Cap 4 - has a gouge in it. You can also see the different color of the 'gray' bearing surface up by my thumb. The rest of it has been polished-off


Front cap:


Some of the rod bearings also had horizontal scars:




All of the rod bearings also had these odd deposits on the bearing surface. Could not be wiped off. Not able to actually feel anything, though




Cam lobes looked ok. This one looked a bit weird. Probably get it polished pre-install


For reference, someone asked to see the oil pump gear on the cam. Here it is - in perfect condition:


Anyway, if anyone wants to offer any ideas, I'm all ears. I don't want to do this again.

I also noticed a lot of oil-scale on the tops of my pistons. I am going to get the heads checked out and make sure the valve seals are good.
 

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The horizontal marks could be from someone measuring bearing clearance before assembly.
Shouldn’t be that pronounced though.

For whatever is embedded in bearing(s).
When it was assembled was assembly lube used? Could have been contaminated/dirty?
 

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The junk in the bearings could be from machining the crank, that was missed in the cleaning process.

Did you check piston pin clearances?

Mic. the bearings and journals for proper clearance.
 

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Discussion Starter #8
Journals on the crank looked fresh from the machine shop. No coolant leaks. I cut open the filter and there were tee-tiny flecks of metal in there, which when coupled with the knock under load, is what led me to pull the engine and tear into it. I am suspicious of the lifters as it appears that some of the external coating on the rollers has started to flake off. Yes, you can catch a nail on these defects. These are Crower 6630 lifters. I am replacing them.




 

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I assume you have communicated with Karl about this and shown pics. What is his opinion?

The lifter wear is concerning as the cam lobes show wear also. Might want to confirm with a machine shop if a "polish" will suffice for the cam or the hardened surface of it has been compromised

Not seeing anything that would cause a "knock"...but checking piston skirt/cyl wall clearance would be prudent

I would put new bearings in for crank & rods since the motor is apart. Ideally the crank will just need a polish
 

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Discussion Starter #10
The cam is shot. I took it out in the sun and gave it a good once-over. All of the lobes show damage that correlates to the damage seen on the lifter surface. Karl has seen all of this, as well as a bunch of videos I've taken over the past few days. The rods have side clearance that is a little too generous for my tastes, as well as his, but he is of the opinion that it isn't the source of the noise. I am leaning towards the oil pump being bad. Its very 'catchy' when turning by hand. That, and the bad lifter(s) were more than likely the cause of the clacking at speed..

This is the worst lobe and has chunks missing. CompCams custom cam via Lloyd Elliot.
 

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yep that cam is junk

I had a custom comp cam wipe a lobe....but that was due to the builder lashing the Comp "R" series lifters 1 1/2 turns. The metal wiped all the bearings....and yeah there was a major "knock" sound in that motor

you caught your issue early before major carnage

The loser rod side clearance may be more the cause of your knock
 

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Quick question,

This engine, you got from Karl as a short bock , right?

You did heads, pan , oil filter adapter, external lines, etc?

I do see a couple of "opps " assembly bits of dirt embedding, that while it would be nice if they weren't there ,are not causing issue.

Lots of dirt going on that may not be tied to initial short block assembly.

Whats the story on the cam and lifters , came with this short block?
Was the valvetrain clattering?
New Billet cam for the win ;)

While it would nice not to leave a mark from repeated checks with a bore gauge on a bearing, it did not cause issue and any one that hasn't done that at least once hasn't built many engines.



Not finger pointing just asking questions.
Gerry
 

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Discussion Starter #13 (Edited)
No offense taken, Gerry. This was a shortblock-only from Karl. Lifters came from Karl as well - they're Crower. Cam was provided from Lloyd. I did the assembly of everything as its not my first rodeo. Way back when, I posted something about one of the lifters not 'feeling right' when setting the lash. Coincidentally, it was the lifter that was on that lobe on the cam. It took at lot less pressure with the wrench when going to 3/4 turn past zero lash. Hindsight being 20/20, I should have given everything a much better inspection than I did at the time. I also had to take the intake off and re-set it due to it sucking oil from the lifter valley, so this thing has been opened up at least twice. Totally likely that I wasn't clean enough in my work and that the dirt was added to it by yours truly.

This is actually the second engine from Karl. The first one had excessive piston slap. It also had a groaning oil pump (Melling 10552) . I noticed the groan when it was primed on the stand. Karl said that the pump is known to make "some noise" and that it was ok to run. That same oil pump was transferred to this ERE shortblock and the groan followed it. With the pump out, it is really really catchy/grabby when turning it. Makes me think that the pump has something wrong with it as well, so I am getting one of the new Melling SharkTooth pumps to replace it.

EDIT: Karl said that he doesn't suggest getting new bearings. He said that they're the top-of-the-line King bearings and that they're made to take a lot of abuse. I pressed him on this and I said I don't have an issue spending the $. His reply was "it's a waste. They're good to go"

To be clear - I don't think Karl's work had anything to do with this failure. Karl's stuff is always top-notch, and continues to be with this engine. It would appear that I got a bad batch of Crower lifters, though.
 

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I’d agree that lifter wear is disturbing.
I’d contact crower and ask if they have any batches known to be bad?

A buddy of mine’s blower was destroyed by 2 bad holley carbs. Delaminating/poor castings blower ate bunch material and had to be rebuilt.
Holley gave him 2 new carbs, but costly for him.
They knew about it too, yet no communication to general public about it.
 

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Discussion Starter #15 (Edited)
Piston pin to piston clearance is wholly within spec, so that's out. Bearings are all within tolerance, so I am going to let them ride, which was Karl's suggestion as well.

I have the filter media I cut open weeks ago that led me to tear down the engine. The metal flake in the filter is eerily similar to the missing metal from the lifter's roller surface. It would make sense that the flakes made their way around the engine before they hit the filter again, or bypassed the filter on cold start, and caused at least some of the scratches in the bearings and (obviously) the cam lobes.

Karl requested I send the images to Lloyd and Crower for their perspective. I suspect Karl is eager to see what Crower says in regards to the failure since he uses these lifters in all of his builds. As Babywag suggests, it could be a bad batch that Crower is either unaware of, or hoping isn't traced back to them. I still have the box-top with some identification #'s, so maybe they've got some info in the books. I personally would love to know which failed first - the cam or the lifters. I suspect the lifters, but I've also read where other CompCam customers have gotten cams that had a failure of the surface-hardening.

Also, Karl agreed with Ballss and thinks that the rod side-clearance could be the source of the knock. If it is, he thinks its more of an annoyance issue than a problem that's detrimental to the engine's longevity.
 

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This is the worst lobe and has chunks missing. CompCams custom cam via Lloyd Elliot.
I had a COMP camshaft do the same thing in my GTO's LS1 with GM lifters. Every single lobe was bad. Luckily no other damage. I've read of similar on the various LS vehicle forums. Needless to say, that car now has a Lunati cam in it.
 

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Atlanta..

Maybe the Crowler lifters were defective, maybe the cam was in terms of its hardened coating...or maybe the lash was to tight. The later I suspect you have done enough to do right

Crowler, like any other parts maker/provider can have a "bad batch". The metallurgy of the stock they get to make the parts may have been corrupt. Maybe they changed suppliers or bought components from a "lower price" source...IDK but it happens. Like the Comp 918 Bee Hive spring fiasco when they switched suppliers. Later a "batch range" of their springs was regarded as bad...I had springs from that batch....and guess what...one broke. So this kind of stuff happens

If the "knock" is due to a wider rod to piston clearance issue that is not going to change if you put those parts back in. IDK how to "fix" that with the same parts...maybe Karl can advise. If different rods, or pistons, are used the rotating assembly will need to be re-balanced

Only good news out of all of this is you caught what would have been more serious engine damage from the failing lifters/cam lobes. Not the reason for your knock but the motor damage at this point from them is no big deal

As Gerry noted, and you confirmed, debris got into engine during assembly beyond short block so lesson learned on being more prudent on work habits putting the next motor together. You are not alone with making that mistake
 

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Discussion Starter #18
As open as I am to taking the hit on making grime inside the engine, it's entirely plausible that the grit seen in the bearings is due to the lifter rollers. Likely, even. Regardless, it is what it is at this point and I can only move forward and be sure to keep near clean-room conditions in reassembly.

Lloyd was of the opinion that the lifters did not show any signs of poor install or valve float. Instead he thinks the lifter surface simply failed, and took out the cam with it. Had I continued to run them, eventually I'd have had a catastrophic cam failure. Good times. I'm looking for other vendors to get the cam from this time.

Now the heads are going off to the machine shop to get the [email protected]*@ temperature sensor drilled out as it appears to have welded itself to the threads. Then they'll have the pressures checked and get all cleaned up.
 

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Like my PM suggested a couple days ago , STEEL cam ?
Even the OE was steel , as opposed to some cast POS.

While there are Melonized gears, ( bronze out of question when you have to pull the intake to inspect-change ) are are also steel billets with pressed on iron gears now.

Since names have been dropped in this thread already,


Advanced Induction - Ai System LT1 Cam Kits
 

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Discussion Starter #20
Like my PM suggested a couple days ago , STEEL cam ?
Even the OE was steel , as opposed to some cast POS.

While there are Melonized gears, ( bronze out of question when you have to pull the intake to inspect-change ) are are also steel billets with pressed on iron gears now.

Since names have been dropped in this thread already,


Advanced Induction - Ai System LT1 Cam Kits
Thanks Gerry. FWIW, I emailed AI and they no longer do cam-only jobs. They will only cut a cam in partnership with a head package.
 
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