What in the World?

pastorjeep

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This is after straightening with rubber mallet so I could remove! What causes this? The lifter seems fine thank God!
 

Macrobb

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I'd check the valve spring on that valve, make sure it isn't broken.

edit:
As for 'why' it happened, the answer ends up being that the piston smacked the valve when it came up, the rocker transmitted that force, and the pushrod was the weak link. Probably something lifter related, if the spring didn't cause it.
 

icanfixall

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No matter what you do please replace that lifter. Clearly the valve smacked the piston. Only two ways that can happen. A bad spring or the lifter pumped up because it failed. Run that cylinder piston to top dead center. Remove the spring and check it. I would do that before I removed the intake.. If you need to remove the intake just to insure the lifter is good or bad please mark where the injection pump is currently. Use a center punch and make a mark in the pump to housing joint line. then you can put it back in the EXACT timing location.
You mentioned in the vid that you were removing the 3 9/16 bolts... Nope... they are nuts with a 9/16 hex.. But we all knew what your intentions were all along...
Are you glad you did not start the engine to test run it before you tore into it...
Make sure you remove the passenger side valve cover too. I realize that is the most tight difficult side because of the clearance issues at the ac box. But not knowing the engine condition is a risk many would not take.
 

pastorjeep

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I had to remove the intake to get the pushrod out, so I will check the spring and pull the lifter in the am. Could a leaking injector cause this? Fill the cylinder/hydro lock? The truck was pouring white smoke and missing a little just before I heard the rod bend and it start backfiring through the intake. Yep, I meant nuts, and the IP was marked...but...I am going back with a reman I have on the shelf and get all the injectors pop tested.
 

pastorjeep

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Well Gary, it is a stuck exhaust valve on #4 cylinder. So I think I will take the head to a machine shop and have the valve and guide replaced.
 

Hydro-idi

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If funds allow, take the other cylinder head off and get them both rebuilt. If your having problems with one valve, it's likely the others will go at some point. This would be a good time to put some studs in, replace both head gaskets etc. while it's already apart.
 

Macrobb

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BTW, do yourself a favor when you do so... don't bother putting valve stem seals on the new heads. My own testing shows it doesn't cause smoke, and no noticeable oil burning, but it should lube the valve guides more than now which should make them last a lot longer.
 

Hydro-idi

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BTW, do yourself a favor when you do so... don't bother putting valve stem seals on the new heads. My own testing shows it doesn't cause smoke, and no noticeable oil burning, but it should lube the valve guides more than now which should make them last a lot longer.

I strongly advise that you do not do this. Valve stem seals are there for a reason. If you have any doubts about the seals preventing oil from lubing the valve stems & guides, you can always buy & install 6.9 seals. I have heard they do a much better job at keeping valves oiled.
Btw, doing so will cause excessive amounts of oil consumption and carbon buildup on valves, especially on a worn engine. I've seen many idi cylinder heads with shot valve stem seals and the carbon buildup is unbelievable. Imagine if they didn't have them
 

Macrobb

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Btw, doing so will cause excessive amounts of oil consumption and carbon buildup on valves, especially on a worn engine. I've seen many idi cylinder heads with shot valve stem seals and the carbon buildup is unbelievable. Imagine if they didn't have them
All of the heads I've seen have lots of carbon buildup on the intake valves, whether the seals were intact or not. I attribute this to the fact that you are sucking engine oil down the intake tract(via the CDR), not the valve stems.
Remember, unlike a gasser, you don't have vacuum(or at least much) on the intake tract. And on the exhaust side, it's neutral to pressure.

Also... I did it, and ran that way for quite a while(separate issue with that motor right now), with no smoke or noticeable oil burning. And the guides on the heads I slapped on that motor definitely had some play.

I honestly expected to see smoke or oil usage, but I'm guessing that without a vacuum to draw oil down the valve guides, it's not really much of a problem.
 

Macrobb

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Don't forget about boost pressure on intake valve guides causing blowby for a turbo engine.
This goes the other way, though. Up through the guide and out into the valve cover chamber.
None of the seals I've seen would affect that at all - they are designed to keep oil out, not pressure in.

Of course, this is also why you want to try to get as much oil as possible into the valve guide...
 

plywood

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Valve cover chamber and then intake then smoke.
Worn valve guides are an issue for turbo trucks.
Wasn't touching on the seal subject.
 
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