I haven't had much luck with used LS engines, they all seem to end up having to be rebuilt-either gummed up, rusty cyl walls, etc.
Anyway, the latest the cam bearings seem fine on the lower side, but slightly rough on the upper side-is this common on what you see-I was just going to throw in a Z06 cam I have, but prob facing another rebuild, lol

 

They all look like that. Run it.

 

X2 Mine looked the same way.

 

Mine too. I hit mine lightly with a little penetrating oil and a green scotchbrite pad to make them smooth again. Go with the bearing if you do it, not across it. I did just enough that it felt smooth with your fingernail.

 

FWIW, scothbrite isn't a good thing to use for bearings. Too abrasive and can embed particles in the babbit. Mahle/Clevite recommends polishing the bearings with newspaper, which seems to work well in my experience.

 

You can get a cam bearing install tool for about $85. Not sure why you would put a new 200-400 plus dollar cam in and scothbright bearings.

 

Newspaper is useless for anything. Whether you want to clean a mirror, polish a boot, or smooth a bearing, newspaper is useless for any of that. Unless you are a homeless person in need of insulation during a cold spell, forget newspaper. BTW, if scotchbrite is too abrasive for something, that something is too soft to go in a motor.

 

Its not a new cam, an old one that had a couple minor rust pits making it unsellable but still useable. I never had good luck installing cam bearings, prob because I tried to make a tool, lol

 

we've had mixed luck with new cam bearings---installed by a fairly decent machine shop.

lost oil pressure and it turned out one of the new cam bearings walked out.

so now we just leave them be. they always look like crap, but the oil pressure is fine.

my .02$

 

GM line hones the block AFTER the cam bearings are installed. Brand new they look like they're shot. Not saying all the time, but I can see issues possibly arising if newly installed bearings aren't honed and are in a journal that isn't perfectly square and true. As far as putting a $200-$400 cam on scotchbrite bearings, is that any worse than just putting it in a junkyard $150 pull-out? Guys do it all the time. Although not favored by some, scotchbriting, newspapering, polishing,etc. bearings all have been done for a long time.

 

Like I said, that's straight from Mahle/Clevite. They may know a thing or two about what you should or shouldn't do with bearings.

 

depending on the application the babbit layer can be really soft. i have no problem believing it could be damaged by scotchbrite--- aluminum oxide bits mixed and extruded with poly propylene

oh man that reminds me of some baloney 90's hotrod crap i used to do....wet sand the babbit layer off down to the bronze IT WAS WORTH 10 HP!!!!!

 

It sounds to me like Mahle really doesn't want you to polish bearings at all, but give you news paper which will do very little, other than make someone feel that they actually did something. I know nothing about polishing bearings, just my take from watching the video.

 

To be fair, that SHOULD be their stance on brand new bearings that they sell you. My comment was directed toward junkyard pulled bearings.