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6.0 Heads and Head Gaskets

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Okay, sorry to drag this topic from the technical to the political but I have recently seen a new resurgence of posts on the "other" web sites about warranty. Specifically, What's the difference between a stock truck that works really hard and pukes coolant and a modified truck that pukes coolant?

Nav has been doing a lot of testing on this issue, and it boils down to overpressurization of the power cylinder. Obviously, mods can cause this, but it's also possible with a stock motor.

 

The most common cause of the problem is heavy acceleration on a cold motor. On a cold motor, there are a bunch of "correction factors" to deal with cold/sluggish engine oil, and it's effect on the injectors. There are also factors that prevent white smoke, and others that account for the fact that some trucks are sluggish when cold. Under certain circumstances, when all of these factors align just right, it's possible for a stock motor to get too much fuel and timing, thus exceeding max CP. That may stress the head gasket, and lead to failure, though the symptoms may take some time to appear.

 

There is some testing being done to determine if altitude also plays a part in this. So far, that does not look to be the case. Both high altitudes and cold conditions generally warrant more timing, but altitude also works to lower CP since the engine doesn't breathe as well. Al things being equal, the whole in-cylinder pressure trace is reduced because the engine starts with a lower manifold pressure. The tests seem to bear this out.

 

So, the most obvious answer to this problem on a stock motor was that it was floored or heavily loaded when cold. Engine oil needs to reach about ~60C to be safe. It has nothing to do with the various rumors of bean counters reducing the # of head bolts, quality of the gasket, etc. It has everything to do with poor code control in respect to the design limits, and mfg'ing variability tolerances. Apparently, some MY and PCM revisions appear to be worse than others, but I don't have any data as to which.

 

Regards,

Jay

 

PS -- The 7.3L also suffered slightly from this same issue. However, the 7.3L injectors were better in the cold, and the motor had a higher "safety limit."

 

PPS -- Every Nav engineer I know notes that they consider the 6.0L as being "chipped from the factory." None recommend any sort of power mods.

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Every Nav engineer I know notes that they consider the 6.0L as being "chipped from the factory." None recommend any sort of power mods.
That has been my position from the beginning. Many owners don't realize that these engines are cranked-up versions of Navistar medium duty designs. Great post by the way :cheers-jeers: but I don't see how it ties into the quote. I think it's funny that chipped and stock engines both exhibit coolant puking and many customers fail to see why the chipped engines are not warranty. Seems like an unfortunate paradox and even "we" have to admit that the rules are sometimes unfair.
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  • 1 month later...

I agree with AMCTech. IHC is an engine and truck company that builds ther own products. Ford subcontracts them out just like Dodge does Cummins. Since Ford cannot compete with Chevy and Dodge with the ICH engine in stock form, they have to "juice" them up. A stock IHC 6.0L puts out just over 200 hp while the Ford 6.0L puts out 350, BIG jump. Yet both can yeild the same torque rate. Throw a chip on top of that and you are asking for it. as far as the gaskets blowing goes, the updated ones have been out for while now and are just slightly thicker (never see it with the naked eye). also the torque sequence has changed. If you replace heads, make sure they have the "Certified" X on them near the exhaust ports.

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  • 3 weeks later...

In a response to another thread on FRT, I measured a stock 2003 6.0L head gasket and a brand new supposedly updated gasket from head gasket kit #5C3Z-6079-B (TSB 05-17-13)Both measure 1.35MM thick with 5 layers. I was told that the gaskets were thicker. Could that have possibly been in reference to the blue sealant printed on the gaskets? /forums/images/%%GRAEMLIN_URL%%/shrug.gif

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  • 2 weeks later...

well it happened ..had to do a set of head/gaskets in the truck ...was unable to lift cab because of firetruck add ons and did not want to pull the engine it is a standard and unable to lift ....so anyways I thaught gee lets follow the book and see how bad it could be...well worst mistake i ever made .. the worst part of the whole job was drivers head bottom last bolt ..book says lift up and secure well there is still no room ..hits fire wall and binds ...comming off not so bad (do not have tobe so gentle as going on ) anyways never again in house will remove engine or lift cab from now on ...oh ya one last note ..torquing the botls down for a 5'10 160lb guy sucks....

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well heres another one for ya ....04 e450 skipping ....injectors 2 and 8 broken ...pieces missing ... also number 4 exhaust rocker retainer ( plastic clip) broken and off ..and the only way to replace it is new rocker ..and the only way to replace the rocker is pulll engine ..makes sense ha ...pull motor to replace a ten cent piece of plastic that is now a ball and spring way to go ford

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after reading about this issue and inspecting heads and gaskets another tech had apart this week i have come to the conclusion that it is the heads that distort not the gaskets failing. the tech noted dark areas on the gasket beetween the cyls and blamed it on combustion gasses although the fire rings were intact. any input would be appreciated.

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I believe Ford calls that discoloration staining and they state that it need not be removed when cleaning the sealing surfaces. I know some guys have replaced heads that were not within specification but the two I have done were damn near perfectly flat after cleaning. I was under the impression that the brownish stains were cooked coolant.

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the 12 or so i have done ...more than have the heads were the issue not the gaskets ...i am talking about the ones that have not been driven till the stop but the ones cust notices coolant pushing out of degas bottle under load ... the heads are always warpped .... /forums/images/%%GRAEMLIN_URL%%/banghead.gif :jeers-cheers:

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We have replaced alot of gaskets since the parts have been available from the TSB. Early on we had one head we did not like so a new one was ordered. The new head had .004" warpage out of the box. Hotline said to use it, so we did. No problems resulted so we rarely do anything but the gaskets. According to TSB 05-24-09 the torque sequence was changed and the torque was increased(on the lower row of bolts). What warpage/pitting we have come across has not resulted in a come-back at this point.

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