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Old 10-06-2019, 07:55 PM   #12
cadillac512
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Join Date: Apr 2019
Location: Kansas
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Default Re: 8ba rod bearing problem

Quote:
Originally Posted by 3739ford View Post
Well, sometimes my memory is not what it use to be. I went back to the barn and the old bearings were .20 under. I found the paper the machine shop guy wrote the bearing sizes down on I needed and it was .30 under. Here are a couple pictures of measurements from my cheap HF tool. The current bearings are .30 under.



Those two measurements are of two different crank journals? The 2.106" is .032" undersize and the 2.115" is .023" undersize! It may be that you have a crank that's been previously ground to different sizes on different journals...was done sometimes back when. Obviously a dial caliper isn't accurate as a mic would be but close enough for what you're diagnosing. You may need to measure with a mic, and maybe either get different bearings for different journals (not the best but will work) or have the crank ground to .030" on all the journals (if the existing ones check out.)



Terry
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