Scotchbrite to clean up rust spot on cam lobe

Overthinking.
More importantly: Did you check lobe taper and lifter crown profiles so you will have rotation? YES? You are good to go to a proper wear in.View attachment 177466

All lash adjusters and cam followers are brand new along with the cams, and the rollers all contact centered on the lobes. I checked cam bearing clearance with plastigage before final installation, and the clearance at all of the journals measures out to between .0017-.0024 which is within spec.
 
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I just called the local dealer to see if they had any of these camshafts in stock while considering my options, and about dropped out of my chair from the insane markup when I asked about the price. He first quotes me $575 for the RH Intake cam when the MSRP is $432, and then says he could sell it for MSRP when I called him out on it. What a bunch of sharks!

I then mentioned that other dealers are selling them online for $288 each, but he says that MSRP is the lowest they would sell it for. I purchased the first set (which I already returned) from a dealer in Illinois that sells online through MyMoparPart.com, and the second set through RockAuto which was drop shipped from a different dealer in Wisconsin all for about $288 each. They all have the correct markings and were packaged in Mopar boxes with recent manufacturing dates.
 
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We do understand that cam lobes are ground to shape using abrasives. Sometimes micro polished with a scotchbrite wheel. Yes, with the very same embedded mix of abrasives, that include silicon carbide, aluminum oxide and Ti dioxide. Depending on the spec.

The risk of abrasives is very real. However they can be cleaned off Without too much effort. Brakeclean is a chlorinated solvent that will do the job well. A variation of which was used for almost a century to clean such parts.
 
We do understand that cam lobes are ground to shape using abrasives. Sometimes micro polished with a scotchbrite wheel. Yes, with the very same embedded mix of abrasives, that include silicon carbide, aluminum oxide and Ti dioxide. Depending on the spec.

The risk of abrasives is very real. However they can be cleaned off Without too much effort. Brakeclean is a chlorinated solvent that will do the job well. A variation of which was used for almost a century to clean such parts.



You are right according to these couple of articles I found. Camshafts and cranks are ground with much harder abrasives than the base material including aluminum oxide, silicon carbide, diamond, and cubic boron nitride superabrasives. Cylinders are typically honed with silicon carbide, aluminum oxide, and diamond. The article on cylinder honing with aluminum oxide states that typical cleaning procedure is just washing with warm soapy water. If harder abrasives tend to embed into softer materials, why isn't this an issue for these processes but is often cited as a concern for an aluminum oxide scotch brite pad?
 
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Lube it up and run it. Sounds as if you made a conscientious attempt to get it clean. A microscopic particle or two won't be noticed by the engine.
 
Don't understand the concern with a 4v roller on the heel. I thought this was about a flat tappet on the ramp or nose.

Weak point again will be the 'torrintons' on the fingers.
 
I got a response from an abrasives engineer at 3M regarding the use of their white scotchbrite pad on the camshaft lobe, and he said it was unlikely the particles would become embedded in the metal. He said that my cleaning process was adequate, and suggested it wouldn't be an issue even if I use the more aggressive maroon colored pad with aluminum oxide abrasive.

I attached the GM service bulletin 00-06-01-012J prohibiting use of scotch brite on engine parts in my email to him, and he commented that these pads are used throughout the automotive industry and there is little concern for the residue when suitable cleaning practices are used. See the attachment for the full response.
 

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I got a response from an abrasives engineer at 3M regarding the use of their white scotchbrite pad on the camshaft lobe, and he said it was unlikely the particles would become embedded in the metal. He said that my cleaning process was adequate, and suggested it wouldn't be an issue even if I use the more aggressive maroon colored pad with aluminum oxide abrasive.

I attached the GM service bulletin 00-06-01-012J prohibiting use of scotch brite on engine parts in my email to him, and he commented that these pads are used throughout the automotive industry and there is little concern for the residue when suitable cleaning practices are used. See the attachment for the full response.
I would tend to believe 3M over the many deceptions GM has pulled over the years or excuses for their quality.
 
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