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Discussion Starter #1
Posting as separate thread for visibility. Made the mistake of replacing connecting rod bushings in my 1974 2L Nord engine. Mistake as in, I have discovered the original bronze bushings are no longer available. What I have appear to be aluminum and do not machine well. After final reaming they feel smooth to the touch, but scratching is visible. Also, cannot get them perfect - see pictures of small gouges. I tried sets from two major suppliers. Both same issues.

Are these ok to use for street use? Car is a fair weather daily driver and used regularly for long distance road trips so I am going for longevity, apparent poor quality surface finish of these bushings makes me worry. The engine shop doing the machining work said not to worry and they are fine, I could use an Alfisti's opinion before I begin bottom end assembly.
 

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I can't tell you how they will hold up.

The machine shop I use has had no problem machining the currently available bushings. I 've had 4 sets done in the last couple of years.
 

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Pin bushings are honed to size, so will show a pattern, but that looks like it was done with 50 grit. So I would be concerned about the work, yes.
Andrew
 

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Discussion Starter #5
Should have mentioned, I brought the machinist the wrist pins as well. He fit each small end to the correct wrist pin. I can't verify his work beyond that other than to note this pattern is concerning. Paul Spruell said not to worry, that these look fine... but as you say @Andrew @mtbjeff the pattern inside the bushing looks to me like it was not done with a fine enough tool. I might bring these to another shop I use and see if they will comment.

Jim do you have any pictures? Do they look smooth and gouge free like one would expect? I'm racking my brains with the variance in opinions about these things.
 

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I have a set of rods just pulled out of a 2002tii, the fit feels very good, will get a pic. There should be no perceptible side movement.
Andrew
 

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Sorry. I don't have any pictures. There all in running engines now.

But the finish looked like very fine honing. Not polished.

Your look like they didn't have the right grit hones to do the job.
 

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Here's one of my tii rods. Not recently honed, but came out of a running engine a couple years ago and I cannot feel any slop by hand. So this is what I'd call a typical running appearance.

Can you feel the grooving on yours with a fingernail?

Andrew
 

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Looking at your pics again, the material looks not just heavily sanded but where the Xs are, torn, like the honing machine was ripping, maybe at too fast an rpm? I'm not a machinist, just commenting on how it appears.
Andrew
 

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Discussion Starter #10
I can feel the large gouges with a fingernail. The mild scratching I can feel too, I checked the original bronze bushings and I can feel that as well. I can't perceive the difference so I won't comment if they are the same. The wrist pins feel like they fit without slop but at any rate, it seems like a good idea to bring these to another shop for a third try as I agree it appears this place likely did not have a fine enough hone. Third time hopefully the charm. I think the place I have rebuilding the engine head should have the resources to do this job.
 
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