Bought core block

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lspann3525

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Oh, I'm sure you know this, but when you torque the main cap bolts to the first torque pass, you are supposed to smack the crankshaft back and then forward a few times each with a dead blow hammer (to seat the thrust bearings). Then proceeded with the final torque-to-angle specs.

Then you should check the crankshaft endplay for specs. A cheap HF magnetic base and dual indicator is best, but I've seen guys use feeler gauges to measure the gap between the thrust bearings and machined surface on the crank.
No I did not know this but thanks. Once I get my hands on some 30w engine oil i'll start the torque sequence I was hoping that assembly lube would work for the bolts the price of oil here is 7 bucks a quart
 

strutaeng

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No I did not know this but thanks. Once I get my hands on some 30w engine oil i'll start the torque sequence I was hoping that assembly lube would work for the bolts the price of oil here is 7 bucks a quart
Here's my adventure on my recent rebuild. I encourage you to see the PDF reference on post #18. Although different displacement, the overall specs should still apply to your engine.


I hope this helps.
 

tom3

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I have a question on the cylinder hone finish. Seems lately I'm not seeing the usual crosshatch pattern. Looking at this refurbed block the cylinder finish seems to be more circular? Is this a new practice? Is this something for the new thinner ring packages? I'd worry some about this.
 
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lspann3525

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That's what I'm confused about now I seen one article online that stated to hand tighten inner bolts then use screw driver or prybar then torque..the other one followed the same procedure you mentioned about torquing the inner bolts first pass then smacking the crankshaft with rubber hammer back and forth.

Which applies to the Gen 3 5.3?
 

strutaeng

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That's what I'm confused about now I seen one article online that stated to hand tighten inner bolts then use screw driver or prybar then torque..the other one followed the same procedure you mentioned about torquing the inner bolts first pass then smacking the crankshaft with rubber hammer back and forth.

Which applies to the Gen 3 5.3?
I'm assuming you are talking about setting the thrust bearings? I used the smacking the crankshaft. It's the method that the author of this book does: https://a.co/d/1iKGrYb

I believe he is a mechanical engineer of some sort fwiw.

But you are right, I've seen a video on YT someone just using a pry bar...

BTW, the "LS" engine families are the same architecture, so this applies to 4.8, 5.3, 5.7, 6.0, 6.2 (Gen III and IV.)
 
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j91z28d1

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smacking the crank back and forth with the bolts tight seems odd to me?


what you're trying to achieve is even contact on top and bottom half of the thrust bearing when the crank is pushed forward by the converter and or clutch. depending.

you don't want to have say the top half of the bearing to touch the crank and the bottom still be off it a thousandth. that would put more load on a smaller section. nothing forces the crank backwards while running, so that's less of a concern.

my experience is this all matter way more in other engines.. the ls isn't know for thrust issues, up until you go drag racing with crazy high stall speeds, but by then you'll have a tranny builder on speed dial haha.

the last one I did, I did the finger tight, pry the crank forward and snug the bolts so the bearing shells don't move. after tq is complete, check your total end play by prying it front and back. as along as that's in spec, shouldn't be a issue.
 
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lspann3525

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Thanks guys. Got the crankshaft torqued and thrush seated. What's the cheapest way to measure??

Also I was looking at the crank and the machine shop said it was fine but I noticed a hair line scratch or crack

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strutaeng

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Hard to tell. Does it catch your fingernail? I think that's going to be fine. I wouldn't really worry about it.

Are you asking about measuring bearing clearances? I assumed the machine shop already did that? If not, plastiguage from AutoZone is really the best way.
 
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lspann3525

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Hard to tell. Does it catch your fingernail? I think that's going to be fine. I wouldn't really worry about it.

Are you asking about measuring bearing clearances? I assumed the machine shop already did that? If not, plastiguage from AutoZone is really the best way.
Yes it does catch my finger nail.

I was trying to measure the thrush bearing to make sure it has been set correctly.
 

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