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Discussion Starter · #21 ·
250k to 280k is around where many cams and liters seem to take a dump. While they have been used in other Powerstrokes and other engines, they are highly stressed in this motor due to the spring load and leverage of the rockers.

In both International's and Ford's manuals, part of the inspection process is to check for deflection, warp, or out-of-flat across the widths. I personally think this is where the major issue is, but it's rare to find people who have checked it. And due to Ford's insistence not to machine the heads, what I call "tenting" is never addressed on many head gasket jobs. Which means they will fail later. The gaskets will not achieve full compression at the center of the head if they are not flat.

The other flatness spec, down the length, is not that important to me, although it should not exceed 0.004". Most machine shops look at the length flatness and call them warped but don't check the width; again, to me, the most critical.

A quick check to see if the head has been machined is to check the head thickness. The minimum spec is 3.74" or 95mm. They can be thicker than that, but many find they are at the minimum from the factory.
That is the kind of detailed explanation that has me lurking so many old posts around here. Thanks and I will ask for that to be checked for sure. I expect a text from the mechanic tonight or tomorrow morning and when it comes I'll ask him about the machine shop inspection.
 

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That is the kind of detailed explanation that has me lurking so many old posts around here. Thanks and I will ask for that to be checked for sure. I expect a text from the mechanic tonight or tomorrow morning and when it comes I'll ask him about the machine shop inspection.
I'm curious, with the failed lifter, did your truck have a tall oil filter cap on it or the shorter one?


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I deeply regretted not changing my heads the first time I tried to fix my truck!


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Without hunting for it, did you have the surfaces machined flat?
 

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Discussion Starter · #25 ·
I'm curious, with the failed lifter, did your truck have a tall oil filter cap on it or the shorter one?


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The IPR kit, unless I'm mistaken replaced the factory cap. I've never heard of it being an issue though.

I deeply regretted not changing my heads the first time I tried to fix my truck!


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That's definitely something I'm thinking about. I trust my mechanic all the way, but to be honest I doubt he's going to suggest I reuse them.

Without hunting for it, did you have the surfaces machined flat?
I can't speak to the previous job because it happened before me, and the current job is in progress. They'll be machined on this one regardless
 
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Without hunting for it, did you have the surfaces machined flat?
I think you were asking me, if so the answer is yes. The machine shop I took mine to said they were out of spec and they machined them. .004 out if I remember correctly. Afterwards I learned that that was actually still in tolerance.
I used UCF Machine shop for the new heads. I sent my old ones back as a core. I actually didn’t think they could be re-used, they appeared that cracked (visibly). They said they were fine to be re-used.
 
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