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The bearings look ok.
More important, how do the journals look?
No nicks and no grooves?
 

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Discussion Starter #4
Thanks. I cant feel anything with my fingernail. The reason for dismantling is because the engine is going to have the edelbrock e street power package mounted (321hp). So i am checking if the bottom of the engine is healthy. I am just debatting with myself wether to get new bearings, While the engine is open anyway. I just have a budget..
 

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Since you have gone this far you might as well check clearances?Plastigauge
 

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I would mike the journals to be on the safe side first, then plastigage. Miking the journals will tell you if they're a) round and b) not tapered and then the plastigage will show you if the crankshaft bore alignment is okay (plastigage in 3 places top and bottom, all the way across the bearing).
 

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the bearings also look good to me, i am a bit concerned, though nothing to worry about, that the journal seems to be a tad larger in the center than on the ends, judging from the polished strip in the center of the bearing. the difference isnt bad, and as i noted isnt anything to really worry about. and it might be just a sharp edge on the oil hole, like the shop didnt chamfer the hole after machining the crank.
 

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Going against the grain versus the above posts, those bearings exhibit signs of contamination. Please see page 8 exhibit 5 of the attached link, your bearing is identical to the second picture. It would be even more obvious on a tri-metal style bearing, not so much on those bi-metal ones. Ideally, the engine is torn down and measured with a quality micrometer on each journal. At minimum, Plastigauge should be used with a new set of bearings that will give you a pretty close idea of what's goin on clearance wise. An experienced machinist can look at the surface finish of the journal and quickly determine if it is scoured and or needs work, if visually visible. There isn't much back story to your original post, but since you claim "it should have been rebuilt about a year ago", it likely was but lacked cleanliness and or prep. Just my opinion on this. However you go, at minimum swap those bearings as they are inexpensive and the ROI is great versus risk.

 

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I'd have to agree with Emberglo. If you have a polished crank journal against a new bearing shell, you should have a smooth wipe pattern. Your wipe pattern points to something abrasive or a journal that wasn't smooth. The clean stripe down the center matches with the oil hole in the block.
 

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Going against the grain versus the above posts, those bearings exhibit signs of contamination. Please see page 8 exhibit 5 of the attached link, your bearing is identical to the second picture. It would be even more obvious on a tri-metal style bearing, not so much on those bi-metal ones. Ideally, the engine is torn down and measured with a quality micrometer on each journal. At minimum, Plastigauge should be used with a new set of bearings that will give you a pretty close idea of what's goin on clearance wise. An experienced machinist can look at the surface finish of the journal and quickly determine if it is scoured and or needs work, if visually visible. There isn't much back story to your original post, but since you claim "it should have been rebuilt about a year ago", it likely was but lacked cleanliness and or prep. Just my opinion on this. However you go, at minimum swap those bearings as they are inexpensive and the ROI is great versus risk.

Looks more like accelerated wear (page 24) to me.
 

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The bearings do look like they were replaced recently. The person simply put new bearings on a used crank. the uneven wear pattern is due to the irregular surface of the used crank. Emberglow is correct there is "some" evidence of contamination but in "my" opinion not enough to cause bearing failure. Putting new bearings on a used crank isn't "always" bad but if the journals are not smooth , you will get this kind of results. The material on the bearing surface ( in this case) is soft and will "move" a bit to compensate for irregularities on the crank as seen by the shiny areas. While not perfect , those bearings "could" be reused.
Randy
 
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