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Need advise on NOS engine bearings (shelf wear)


JP75

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Hi,

I have an opportunity to purchase a set of NORS rod bearings but, after speaking with the seller I am unsure if they are sound parts. (I can get new but, I prefer period parts if available) Some of the bearings have self wear very fine micro scratches from the cardboard box tabs that laid on the bearing for years. Also 1 bearing has a finger print. I have read this could happen on old bearings and I am guessing this one was touched years ago and then put away. My question is should I pass on these parts or are these cosmetic issues that will not cause any problems? I have been able to find a little bit of information on how the finger print issue is created but, none of the articles state if the bearings were compromised if this happens and no information about what appears to be shelf wear from the cardboard box.

Thanks for your help.

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For what it's worth. I retired from a nuclear research reactor facility. Over my years there, I threw away bearing worth many thousands of dollars due to them setting on the shelf too long. Here's the problem....the earth is always moving, nothing you can feel, but it is moving. As these bearings set on a shelf without being spun once in a while, the earths vibrations will flat spot the ball or roller bearing in contact with the race. Now, these bearing were ,most of the time, very large. How this might effect bearings weighing much less, I have no idea.

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Hi again thanks for the quick responses but, I want to make sure we are all on the same page. These are rod bearings not ball bearings and the old finger print is etched into the bearing and not just a print like on glass. supposedly the oils on your skin mark the surface if left to sit.

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For what it's worth. I retired from a nuclear research reactor facility. Over my years there, I threw away bearing worth many thousands of dollars due to them setting on the shelf too long. Here's the problem....the earth is always moving, nothing you can feel, but it is moving. As these bearings set on a shelf without being spun once in a while, the earths vibrations will flat spot the ball or roller bearing in contact with the race. Now, these bearing were ,most of the time, very large. How this might effect bearings weighing much less, I have no idea.

Was this a government position that you retired from?

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Sorry, I missed that part. If a ball or roller is not involved then this is a mute point.

On the other matter. I worked for a government contractor, Oak Ridge National Labs. They have the highest flux density of neutrons in the world (HFIR). Although I worked in an area devoted to helping mankind move forward such as makingCalifornium 241 (used in cancer treatment), I always liked the saying, "Built in Oak Ridge, tested in Japan".

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I really doubt that the finger print will have any effect. The finger print probably is just a few microns deep and typical bearing clearances are a whole lot more.

Since I dont know what engine you will be using the bearings on, there are different hardnesses and materials used for bearing surfaces. The softer the surface (say plain babbit) the more careful you have to be in cleaning the bearings.

If I were cleaning the bearings for my use, I'd stay away from anything that might be abrasive. Abrasives can imbed in bearings no matter how fine.

As far as the fingerprints go, If the bearings were mine I'd go ahead and use them.

As an aside. It is there is an abrasive called "TIME SAVER" that is used to run in and seat bronze bearings (in my case). It is some kind of a very, very fine "lead / abrasive" powder that when applied, will disipate quickly. I havnt heard of it being used in automotive applications. Any comments on that?

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Guest 1910_Anon

OK...

Lets think about this LOGICALLY rather than technically (even though this is on the technical board)

YOU have a question about the condition of the bearings.

Therefore: in your mind, the condition of the bearings is in question.

The last place where you want to have questionable parts are the rod bearings. The Question "are they are as good as new?" or even "are they good enough" can never be answered no matter how you try to clean them and you WILL worry about it every time you drive the car (especially if new bearings are readily available).

Ergo: Put new-new-stock bearings IN the engine. (And if you want, buy the NOS bearings, clean them up if desired and show them off to your friends Outside of the Engine.)

Q.E.D.

P.S. I see that Rusty posted while I was typing. His final line goes double in your case since you have not bought the bearings yet so nothing is lost.....

Edited by 1910_Anon
include more scope (see edit history)
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Look at some old bearings that were doing fine, not worn, and still measure at original oil clearance to the crank. You will be appalled at what the bearings look like.

Scotch bright as long as you don't grind it into the surface works fine. so does fine sandpaper, like 600 wet or dry. Just use some sense and clean off the bearing's surface afterwards.

GLong.

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