Maybe the injector being tight in the bore is a sign of slight warpage of the head and that warpage is whats jamming up the valve stem?

This is yet another dropped valve at the rear of the head.
Why are there never any broken valves at cylinder #1?
I'm seeing a pattern here.

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U.S. Army Retired

To be honest, I don't know. I thought the first time it was jammed because of all the grime and crap that was around the injector body. Don't forget that these bores are enormous, and only really sealed by the crush washer at the bottom, and the O-ring for dirt and debris. It might have been stuck today because of all the damage underneath. The end of the valve stem was shoved right through the glow plug hole. So it's possible that it was actually jamming the injector hole too.

Fixed the pictures. What may not be obvious is that the piston is NOT LEVEL in the cylinder anymore. When you rotate the crank, there is a slight movement of the other pistons... The #4 doesn't budge. Then there is a *clunk* heard from UNDER the #4... And still no motion in the crown.

If this is like the one that a dealership in Atlanta destroyed, the entire piston may be cocked sideways in the bore. This kind of violence happens at 70mph / 2000+ rpm when big bits leave their assigned duty stations. I am still wondering if the valve stem snapped first halfway up the guide and just fell in. As you can see from the bits on top of the fuse box, the top of the stem was picked up from above (and was next to the rocker gallery laying flat on the top of the head) and is cleanly sheared off. WTF is going on with these engines?

If someone could prove beyond a reasonable doubt what the flaw is, I'd happily pay them $200.

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Proud supporting vendor of LOST Jeeps
TRAVELING CRD TECH. I come to you!
Need help? Just ask! I've taken it apart more than most.
Email jeep [at] maincomputer [dot] com - BOARD MESSAGING IS BROKEN
Over 225 CRDs currently driving with my valves, timing belt, rockers, or ARP Studs.
Bad noises = REALLY bad things.

Yeah, all this madness convinced me to put an almost new head on mine vs the 1 for 1 ARP's. But, I had one lying around I got off another CRD, and my engine has 180k miles on it. I'm still paranoid about the valve on mine that snapped a misplaced rocker in half (previous owners failure, probably a dealerships work), and I wished I would have just had the machine shop replace it. They did say it was strait

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05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Can you post a high resolution closeup of the fracture surface in the upper half of the valve stem? Assuming it hasn't been beaten up, some information could be gleaned from that, but you really need a microscope.

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05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

Another dropped valve, in the rear half of the engine. Hmmmm.......

I can't, but only because I don't have the parts. Naturist (the owner) may be able to get some scans of this though. The bits are wrapped in a glove in the parts bucket in the back of the car so they are all together and protected. The rest of the valve stem is still jammed in the bottom of the head which is also in the back of the car.

I'll ask him if he can scan this at work or something, he might have access to an electron microscope. I'm not sure what it will show, but I'm also not a metallurgist.

Before you removed the head did you check to see if the timing was still correct? After such an impact I guess it broke the belt or caused a cam sprocket to slip but it would be nice to know what you discovered.

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2005 KJ RENAGADE 2.8 CRD 6 SPEED NP242 FULLTIME 4X4

I discovered that the crank would move only about 10-15 degrees. Checking the timing was not an option.

The biggest discovery was that the piston was stopped at TDC, and the crank would still move only 10-15 degrees with the pistons exposed. The #4 had no signs of motion, but there was a *clunk* from below the crown of that piston. Obvious rod damage.

At that point, it was obvious that this was a confirmed kill. I want to know what is the root cause for this like you have no idea. The *only* thought I have at the moment is that the oil just is not staying clean enough and is gumming in the passages. I would not suggest shorter change intervals OR any kind of additives to treat the problem however. The only thing I would suggest is the Amsoil bypass filtration kit. If the oil is then returned by a port tapped into the valve cover, it can help lube the top of the valve stems from there with freshly-purified oil and maybe that will offer some help. As it is right now, I am dubious about the head design overall, and deeply concerned about how to get more oil to the areas that need it most.

There is a pressure port right on the front of the engine or three on the main gallery that the oil kit can pull from, all you need to do is get it past the belt or the turbo and up to the top to meet the filter kit.

Actually, while the vehicle had 200,000 miles on it, the head was only at 50,000 miles. The original head gasket blew and the original head cracked at 150,000 miles, and a reconditioned head was installed at that point.

The turbo has no play at all that I can feel, and while Tanner has expressed interest, he's "thinking about it." Somebody else already got the ECU, but everything else is still up for grabs. I will be posting some pictures of my own as soon as the sun comes out (currently raining here).

x2 with concern of lack of lubrication going to the rockers and cam shafts. My 2005 crd even after a total rebuild including new rockers and lash adjusters sounds a bit like they are not taking up the slack, its ok on short journeys but after a 100 plus mile constant journey it seems to get more noticeable.
I installed an oil pressure gauge to monitor oil pressure and that's fine so its not oil pressure related but maybe the lack of oil flow to the head. My older 2003 crd always sounded good and removing the oil filler cap would coat you in sprayed oil, on this 2005 hardly a spot of oil? Maybe they decreased oil flow to the head to help increase oil pressure for the bottom end but than I am just speculating.
Good luck with it and hope an answer can be found.

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2005 KJ RENAGADE 2.8 CRD 6 SPEED NP242 FULLTIME 4X4

Looking at the photo of the piston it don't look like its laying flat with the block.
I have heard of a few cases that a piston has broken into 2 at the gudgeon pin/ wrist pin. might be worth seeing if you can pull the top part of the piston out of the bore. But even if broken I guess it would be difficult to know if it was broken by the valve or the valve broken by the piston. What was first chicken or the egg.

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2005 KJ RENAGADE 2.8 CRD 6 SPEED NP242 FULLTIME 4X4

The top of the piston is not even with the top of the block. There is no doubt whatever that the piston lies cockeyed in the cylinder. In fact, we did try to move it via turning the crankshaft, and that piston is solidly frozen in place. Don't know how you'd pull the top of the piston out, there's really nothing good there to grab on to.

The valve stem sticks out of the head like the curly tail of a piglet.

There have been enough folks asking for photos, so I guess I, a professional photographer, have been summoned to work, eh?