The head still looks OK in the photos. I've seen worse that were reused. Go look for a junk engine. Pull both the piston and liner and swap them. If the head looks better, then swap it as well. The interior only looks like it needs to be restuffed. Give it a chance.

Go for it.
 

Nothing wrong in just replacing the damaged parts. At least that's my experience from replacing a bent connecting rod in my S350. Cylinder walls do not look too bad. Do remember to compare the connecting rod lengths to see if the force from the ball bent it. You could go crazy replacing every little wear part and spend thousands in a rebuild, but that's overkill IMHO. Use Hylomar on the head gasket when you reassemble. Worst case is that it dies after another 20 kmi. Could go another 100. If the head's not cracked, I'd use it as-is. the indents will lower compression a bit, but it will still run. Your potential loss is about $400 in parts and some time that will be a good learning experience. I had a blast when I did mine.

-Dave Walton
87SDL, 94S350, 99E300

Glad I followed up on this post. Too bad about your engine, I wonder if the Dents were caused by the original pc chunks, the GP end, or parts of the PC? can you tell what the piece of embedded metal is? the large hole in the pc let the gp end drop in? hard to belive. maybe something fell into the open GP hole before you got the new one in... those dents are from something SOLID, I can't believe the gp end is that sturdy. pull it out of the piston and find out what it is.
it may be a berring from something else like a turbo gone south and finding it's way into the intake and be completely unrelated to the GP booboo.
John

Interesting, verrrrrryyyyy interesting....
 

Is that li'l metal ball, the metal embedded in the piston crown...solid??

It almost looks as if it is a ball bearing from somewhere......

I looked at all of the photos......I don't think that little metal ball is from anywhere within the Injection system/prechamber......

could you post a photo of the intake valve port, for that cylinder??

So far, my train of thought seems to lead to a "foreign" object passing from the air cleaner, thru the turbo....and then kicked up into the engine.....it just happened to land in that particular cylinder......

SB

the pictures in this thread are stunning, but...What is the ball for? does it serve a purpose like the marble in a spray can?

Answer
 

The ball improves aerosolization = better combustion.

Precombustion chamber
http://en.wikipedia.org/wiki/Indirect_injection#Precombustion_chamber

diesel injector prechamber aerosolization
http://www.google.com/search?hl=en&rls=com.microsoft:en-us&ei=oH49S7nRKY7mnAfO1ciBCQ&sa=X&oi=spell&resnum=0&ct=result&cd=1&ved=0CA0QBSgA&q=diesel+injector+p rechamber+aerosolization&spell=1

I'll second that sentiment. W116's were a giant leap forward in their day. Sad to see them dropping off the roles of daily drivers....

And, what's the theory behind the huge holes in the sides of the prechamber? As I recall the little ball is attached to a thin rod with a wider flange at the end that "fills" the hole it is inserted through. What caused it to come off? Maybe I have been lucky, but I have never seen one come loose. I have seen them pitted and eaten away, but never loose. And looking like such a ball. I see no evidence of the rod it is mounted on in the photos.

Oh well, sorry to see this end so dismally.

Jim

The shaft that the ball rides on is pressed into the side wall of the prechamber. Over time, this connection loosens. On the SD at 180K, the shafts were all a bit loose. They were not in danger of disengaging from the wall of the prechamber, but the guess from Metric was that they wouldn't go another 100K. I replaced them all.

I believe it's quite common for these shafts to get loose once the engine gets over 200K. Whether they disengage is anyone's guess. I suppose it is related to the manufacturing process of the prechamber. The thin outer wall of the prechamber is not ideal for holding the shaft for an indefinite period of time.

I have never dissected a prechamber so I am not clear on how the ball is mounted on the shaft, but I thought it was actually one piece from peering at it through the opening the injector screws into. I also thought it was anchored on both sides, not cantilevered from one side. Again, based on gross observations. The ball in his photo in one of the earlier posts with pictures shows what looks like a pretty intact ball. Just seemed peculiar to me - the shaft it was mounted on is gone, and the ball is intact, without any evidence of a shaft having been attached or a through hole for the shaft to go through. Just seemed odd.

Jim
Jim

Yes, the ball and shaft are one piece and the shaft is anchored on both sides in the wall of the prechamber.

I can't explain the presence of an intact ball unless the "shafts" have disintegrated. They are quite thin near the prechamber wall.

And it seems the holes the little "flanges" at each end of the shaft are shrink fitted into have also departed, leaving a large hole. The one side shown in the photo shows the damage from shearing the glow plug shaft off. I wonder what the other side looks like?

The photo of the bore in the head the prechamber fits into looks like the entry into the main combustion chamber above the piston and under the valves seems intact - other than where one of those "flanges" appears to have pounded an indentation, but at a diameter that would be closed off by the inner tip of the prechamber once installed. Which, in the photos does not seem particularly damaged . The observations would lead one to conclude the design, intended to preclude the shaft ends or ball from dropping into the combustion chamber, was still capable of achieving its design intent. All very mysterious.

Jim