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  #91  
Old 08-15-2019, 10:52 PM
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MetalWolf MetalWolf is offline
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10/10 on the crank is good, not a lot of loss there. anything more and I would have just replaced the crank with a new one. I've seen shops turn em 20/10 and 20/20 and that is to some people acceptable, but, not to my standards.

Seal power is a good product use to be another one called, Perfect circle, haven't seen them around in a while though... use to use those and TRW but seem to have been bought out or just disappeared over the years.

Sounds like you're well on your way now we await the build pics.
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  #92  
Old 08-16-2019, 08:57 AM
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Shade Tree Welder Shade Tree Welder is offline
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10/10 on the crank is good, not a lot of loss there. anything more and I would have just replaced the crank with a new one. I've seen shops turn em 20/10 and 20/20 and that is to some people acceptable, but, not to my standards.
On the 2" bearings I'd have no issues with going more,
it's a daily driver not a performance engine.
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  #93  
Old 08-16-2019, 08:57 PM
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On the 2" bearings I'd have no issues with going more,
it's a daily driver not a performance engine.
No, I would agree if it's a daily driver not intending to pull a trailer loaded seen too many 20/10 and 20/20 cranks fail. older models of course maybe the more modern cranks are tougher now... don't know that to be true but anything I would build for a work truck having to pul a load I'd stay with stock or turn max 10/10...

But then again these things are, all one's, personal preference.
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  #94  
Old 08-16-2019, 09:09 PM
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Shade Tree Welder Shade Tree Welder is offline
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No, I would agree if it's a daily driver not intending to pull a trailer loaded seen too many 20/10 and 20/20 cranks fail. older models of course maybe the more modern cranks are tougher now... don't know that to be true but anything I would build for a work truck having to pull a load I'd stay with stock or turn max 10/10...

But then again these things are, all one's, personal preference.
Come on its only a 318, it's not like it has any real power...
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  #95  
Old 08-16-2019, 09:43 PM
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Come on its only a 318, it's not like it has any real power...
Ok Point made and received... LOL!
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  #96  
Old 08-17-2019, 04:33 AM
Rob65 Rob65 is offline
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Default Dodgy Engine Rebuild (318 / 5.2L)

I think that the issue with reground cranks breaking has more to do with the radius where the ground journal surface meets the crank web than the actual diameter of the crank journal being slightly reduced.

If the regrinder dresses the grinding wheel straight across and does not radius the corners of the wheel it leaves a sharp corner at either side of the ground journal, this caused a massive localised increase in stress at that point when the engine is running.

I have a little 3 cylinder diesel here I bought with a broken crank that snapped due to this, straight after being rebuilt.

Rob

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Last edited by Rob65; 08-17-2019 at 04:43 AM.
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  #97  
Old 08-17-2019, 10:12 AM
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I think that the issue with reground cranks breaking has more to do with the radius where the ground journal surface meets the crank web than the actual diameter of the crank journal being slightly reduced.

If the regrinder dresses the grinding wheel straight across and does not radius the corners of the wheel it leaves a sharp corner at either side of the ground journal, this caused a massive localised increase in stress at that point when the engine is running.

I have a little 3 cylinder diesel here I bought with a broken crank that snapped due to this, straight after being rebuilt.

Rob
You are correct.

And the guy who ground the crank should be beaten with it.
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  #98  
Old 08-17-2019, 04:21 PM
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No doubt you are correct but there are some cranks you can get away with it and some ya can't, but the safe way is nothing more than 10/10 anything more is a risk... cast cranks predominantly nothing more than 10/10

use to be a nationwide engine builder can't remember the name but they use to put out some squarely shit. engine blocks would be bored different sizes from 10 to 40 over.... cranks turned 10, 20 and even 30 on the same rank shaft needless to say they didn't last long but did last more than 10 years screwing people.

And people would wonder why it runs so rough and never lasts more than a couple of months. that was way back in the day before the dealerships came out with crate engines those Target Masters and they were affordable decent replacement engines. then not long after that Autozone started selling crate engines.
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  #99  
Old 08-17-2019, 09:09 PM
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SmokinDodge SmokinDodge is offline
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Originally Posted by MetalWolf View Post
No, I would agree if it's a daily driver not intending to pull a trailer loaded seen too many 20/10 and 20/20 cranks fail. older models of course maybe the more modern cranks are tougher now... don't know that to be true but anything I would build for a work truck having to pul a load I'd stay with stock or turn max 10/10...

But then again these things are, all one's, personal preference.
That’s complete and utter bullshit. If 20 thou is gonna make a difference you didn’t have an engine or crank to begin with.

Class 5,6,7 and 8 trucks get their cranks ground under all the time. I have no issue with one being 20/20 under, even saw a late model cumins reman that was 20/20.

And no, it’s not personal preferences, most any OEM sets the precedence for what is acceptable by factory spec and bearing availability.
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  #100  
Old 08-17-2019, 10:51 PM
JBFab JBFab is offline
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Agreed. I also agree with a previous poster that the radius at the edge of the wheel is far more critical than how much is taken off.
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Originally Posted by SmokinDodge View Post
That’s complete and utter bullshit. If 20 thou is gonna make a difference you didn’t have an engine or crank to begin with.

Class 5,6,7 and 8 trucks get their cranks ground under all the time. I have no issue with one being 20/20 under, even saw a late model cumins reman that was 20/20.

And no, it’s not personal preferences, most any OEM sets the precedence for what is acceptable by factory spec and bearing availability.
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