Next step before committing to anything might be to see if getting a small camera through the spark plug hole would be possible. These tools used to be on the expensive side, but I believe some members have used cheap USB cameras off of eBay for work like this. Might tell you if the problem is, in fact, a dropped valve seat, or something else like a head gasket or some foreign object keeping a valve open. Might even be possible to get the camera in through the intake port for a different angle. Just a thought, but I agree with others that it is looking increasingly likely the head will have to come off.

Best of luck, keep us posted.

 

Hi... So it goes.... See attached pictures.

I made progress today. Was also able to have a conversation with a mechanic I like down the street. He tried (it seemed) to scare the BEEJesus outah me about the job. I took note, then headed right home and got to work... Took off the things I needed to,,,, to GIT to the things I needed to GIT to,,,, and OFF cam the intake manifold. And BAM! There it was. One good sized piece and a few small chips of an intake valve seat (the intake valve closest to the firewall) that had dropped and was blown back up and into the intake manifold. When I took the manifold off they were rattling around in there. With a shake - they hit the floor. I was like DAMN... All that engine digging with more to go, for that.

Then, looking down into the space, the intake inlet for the corresponding valve, I could easily see (I dont know if you can make it out in this picture) a big old chip broken off of the area that "holds" the seat around the valve... The aluminum seat frame setting.

I have a camera coming but dont think I'll need it now. Tomorrow I'll finish the pull and get the Cylinder Head off. I have a couple of questions. One is to do with removing the harmonic dampner, to remove timing chain cover. What can I do to stop it from turning while I try to loosen the 24mm bolt that holds the dampner to the crank shaft? The second,,, is looking for tips on actually pulling the harmonic balancer..? I hate the specialty tools thing - but I've read that all other pullys simply bend under the load of pulling the harmonic. Any suggestions would be welcome.

Anyways there is a $196 dollar XK8 Cylinder head on ebay that I DONT have the cash for right now but SHOULD tomorrow. But I'll have to see something after taking the head off ---- I will pray that the bore, the piston and area in the cylinder is not to beat up from the pieces that didnt end up in the intake manifold. Im guessing (praying) that the missing parts of the ring (see pic) shot out of the exhaust quickly. We'll see how badly it roughed up the bore, cylinder and other exhaust valve outlet area and,,, tomorrow.

More pics to come. Pics below. Advice welcomed...

http://imageshack.com/a/img923/6873/f0bxvA.jpg
http://imageshack.com/a/img923/2642/JmIlkx.jpg
http://imageshack.com/a/img921/8996/EVsEZU.jpg