Help!!! With getting main bearing to roll in

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80BrownK10

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I rolled out my rear main bearing but can't seem to get the new one in. It hits the block. There .010 bearings like the crank was stamped. I don't have a mic but used my calipers to measure the leading edge of the bearing and it measures the same as the old.
I have all main caps loose what are some tricks here.

Only think that comes to mind is to taper that edge against the block so it will start but something tells me that's probably not a good idea:evillol:.
 

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I'm not sure if loosening every bolt that holds the crank in place will help, (from the balancer to transmission)
 

80BrownK10

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I'm not sure if loosening every bolt that holds the crank in place will help, (from the balancer to transmission)
I have done that. So do you think I need to snug them all back up? They were snug at first and it didn't help. I'm my mind it I thought would allow some tiny, tiny amount of droop. But it seems to not have mattered
 

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Are you doing them one at the time with all caps slightly loose? Few months ago I did same procedure on my elco. Would just lay oiled half on the journal and it would roll in.
 
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I've done this several times with no problems.... hmm.
 

80BrownK10

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Are you doing them one at the time with all caps slightly loose? Few months ago I did same procedure on my elco. Would just lay oiled half on the journal and it would roll in.
Yes that's what I tried.
 

80BrownK10

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Are you doing them one at the time with all caps slightly loose? Few months ago I did same procedure on my elco. Would just lay oiled half on the journal and it would roll in.
Yes that's what I
I've done this several times with no problems.... hmm.
I have found a fourm where a guy had the same problem, he eventually got it, never said how he got it though.

Maybe my cotter pin that keeps slipping is too small to roll it in effectively?
 

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If you have a standard transmission maybe the input shaft is holding the crank up, if an automatic maybe it's the torque converter/flexplate.
 

80BrownK10

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Success!! I even went as far as loosening the flex plate bolts.

I kept looking closely and noticed it was the thrust side of the bearing that was hitting the block. It was the inward side. I have been dinking around for hours with this think. About six blows on a counter weight on the crank with my small dead low and it moved the crank back the thousand of an inch or so that I needed. I was able to start it by hand then roll it in with the cotter pin. I was starting to have visions of having to pull this motor to fix this:oops::rolleyes:
 
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idahovette

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Ata boy Nate.....whiskey or beer always helps!!! Glad you got it
 

QBuff02

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Success!! I even went as far as loosening the flex plate bolts.

I kept looking closely and noticed it was the thrust side of the bearing that was hitting the block. It was the inward side. I have been dinking around for hours with this think. About six blows on a counter weight on the crank with my small dead low and it moved the crank back the thousand of an inch or so that I needed. I was able to start it by hand then roll it in with the cotter pin. I was starting to have visions of having to pull this motor to fix this:oops::rolleyes:
This is correct, when most main bearings have wear the thrust bearing is worn as well. Generally a flat blade screw driver or small prybar used to pry between a crankshaft counterweight and the main webbing on the block is all that is needed to move the crank forward enough to get the new bearing in.
 

80BrownK10

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This is correct, when most main bearings have wear the thrust bearing is worn as well. Generally a flat blade screw driver or small prybar used to pry between a crankshaft counterweight and the main webbing on the block is all that is needed to move the crank forward enough to get the new bearing in.
I tried this but couldn't get the prybar I had in hand in and was also worried about what I was prying against. Good tip , and hope this will help others in future.
 

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