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Posted

Get a mechanics stethoscope, have a listen at valve covers, oil pan.

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Posted
On 5/27/2023 at 6:12 PM, swathdiver said:

 

Fellas, should he do a compression test first?  Inspect the plugs first and do a compression test.

 

 

That and a leakdown

 

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Posted
On 5/27/2023 at 6:12 PM, swathdiver said:

 

Fellas, should he do a compression test first?  Inspect the plugs first and do a compression test.

 

 

That and a leakdown

 

  • Like 2
Posted
On 5/26/2023 at 3:39 PM, newdude said:

That sounds like a broken valve spring or a shot cam.  

 

Or its a rod about ready to depart the block.

 

Either way, time to open it up.  

 

You nailed it on the rod. The bearing was gone on the cylinder I could here the knock the best on.

I have a new question, the crank and rods do not have visible signs of wear fitting metal on metal contact. What I mean by that is the are smooth with no tracking. However, I am noticing where the bearing was shot that the crank has a noticeable step on the compression side and if I didn’t know any better I would assume it was turned that was. 
 

Is it possible to just replace the bearings or do I need a new crankshaft?

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Posted
On 5/28/2023 at 7:32 AM, diyer2 said:

Get a mechanics stethoscope, have a listen at valve covers, oil pan.

I did use one, the knock only resonated through one cylinder, but all lifters, injectors, and valves were functioning and consistent. I didn’t check the oil pan with it, but did pull it today and it is a rod bearing failure.

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Posted

Shaun, Thank you for posting your knocking problem and especially for your follow through.  I am experiencing the same issues.  The video you posted was spot on!  I knew better than trying to drive it but I was just as cautious in running the engine at idle to isolate the sound.  I’m new to the forum and I’m grateful to all who shared their experiences and processes of troubleshooting.  I’ll perform my due diligence and ask in advance for any counsel available.  “Put me in coach!”

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Posted
10 hours ago, Shaun Toole said:

I have a new question, the crank and rods do not have visible signs of wear fitting metal on metal contact. What I mean by that is the are smooth with no tracking. However, I am noticing where the bearing was shot that the crank has a noticeable step on the compression side and if I didn’t know any better I would assume it was turned that was. 
 

Is it possible to just replace the bearings or do I need a new crankshaft?

IMG_2624.jpeg

IMG_2621.jpeg

IMG_2620.jpeg

I haven't done a motor in years but a machine shop can tell you whether that can be fixed and run larger bearings to compensate.  Used cranks are plentiful I'm told.

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Posted
On 5/29/2023 at 5:11 PM, Christopher Strode said:

Shaun, Thank you for posting your knocking problem and especially for your follow through.  I am experiencing the same issues.  The video you posted was spot on!  I knew better than trying to drive it but I was just as cautious in running the engine at idle to isolate the sound.  I’m new to the forum and I’m grateful to all who shared their experiences and processes of troubleshooting.  I’ll perform my due diligence and ask in advance for any counsel available.  “Put me in coach!”

My neighbor worked as a machinist for GM, the other an engineer for them but only on conflicts. This forum has been super helpful to say the least because “just replace it” isn’t helpful on a $6,000 engine. I’ll post a follow up when I get it back together. It’s a very doable project considering I’m doing it on a gravel driveway in 90 degree weather.

Posted

Good Luck Shaun. To be young and determined, that's a good thing.

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