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Old 02-12-2011, 03:09 AM   #1
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Default is this ok? (bearing questions...) with pics :)

hey i was pulling apart this motor and all the bearings exept the center crank bearing looks in very good shape...

this is that #1-#2-#4-#5 look like:

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but the center #3 looks like this... it looks like the crank hasnt touched the outside edge of the bearing...
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is that bad or is that ok?

also, the end play (thrust bearings) on the crank is at 8 tho of an inch, is that ok? my book says 11 to 31 tho of an inch is "with-in spec"... but i just want to check with the pros
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Old 02-12-2011, 03:16 AM   #2
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Replace them.
They are cheap.
They definitely have a good bit of wear on them.

NOT replacing them would be plain stupid.
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Old 02-12-2011, 12:05 PM   #3
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You got it apart, replace them all. Cheapng out here wil just provide you an opportunity to tear it all down again when it spins one.

Put it this way: is it worth pulling an engine to save less than $100?
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Old 02-12-2011, 01:47 PM   #4
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Quote:
Originally Posted by rleete View Post
put it this way: Is it worth pulling an engine to save less than $100?
+1^
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Old 02-12-2011, 06:49 PM   #5
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What everyone said. Shouldn't even be a question. If I'm tearing apart an engine, its getting new bearings.
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Old 02-12-2011, 08:32 PM   #6
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Just reread this. If your question is about #3, that's perfectly normal. A bit undersized journal will do that. Nothing to worry about. Forces on the crank are roughly parallel to the bolts holding in the bearing caps, so side play is nothing, and is compensated for by the other journals anyway.

End play is great. Less than 11 is perfect. Use lots of assembly lube and that motor will be fine.
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Old 02-13-2011, 07:54 PM   #7
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the only reason i wasnt looking to replace them is that im building this motor for a friend and its kind of a budget-ish build...
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Old 02-13-2011, 08:18 PM   #8
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Cut corners other places. You want a good gasket set, and new bearings. It just isn't worth it to cheap out, and have to do it all over - incuring more cost overall.

Hell, as cheap as I am, I'm even lazier. T do it twice would make me want to kick myself.
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Old 02-13-2011, 08:23 PM   #9
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Budget or not, its like taking a shower and putting on dirty underwear.
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Old 02-14-2011, 09:53 AM   #10
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they look warn just replace them like everyone else says so you will not have problems down the road.
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Old 02-14-2011, 06:01 PM   #11
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ok thanks guys... talked to the guy and we are replacing them...
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