These are not the best plugs for these cars...

When I got my xk8 it had a dropped valve seat. A way to check is to pull of the plastic intake housing on the top of the engine and shine a strong light into the hole created by pulling off the intake plenum (on 8) and seeing what you can see. Another is to take a cheap camera plugged into your phone and poking it down the 8 spark plugs hole to look for damage and dents on the top of the piston on 8. Once the camera is in the bore/cylinder you may be able to get lucky and get the camera looking UP to see what you can see...

Don't run the car. A lot of unburned gas will make it into the CAT and then youll have another set of problems.

 

lt will look like the one on the left, or you may find the bits in the intake like jayjagjay. lm in the same boat as you.

 

Yup! Exactly that. Thanks for the boost, Mark!
Cheers!

 

2 bolts cam loose on top row with air ratchet. then the tool became rounded and will not work. the air ratchet cannot even fit for lower bolts

this was a new snap-on socket. most other makes are too large in diameter to fit down bolt access hole

any suggestions

 

I will start the engine removal process next week

 

Before I yank the engine I thought I would give those bolt extractors a try
so i tried rocketsocket 13 mm and got 1 off and the rocketsocket split in two on the next bolt (:
It seems some 1/2" drive sockets fit in the hole and others do not.
I have some 1/2" drive 13 mm 6pt deep sockets arriving this week.
I may try some 1/2" drive 1/2" 6 pt deep sockets

 

The 3/8 drive impact sockets just have too much slop in the hole and gave me some rounding of the bolt head. Same for the 3/8 chrome sockets. And nearly all the 1/2 inch drive impact sockets are too large in OD to fit. So I had a couple machined down to within .01 inch of the hole and these then are stable and I was able to undo all but one of the bolts. The last bolt was the one the broke the 13mm rocketsocket. I used a dremel tool extender to remove the rounded shoulders and was able to use the 12 mm rocket socket to remove the last bolt.

 

I got the heads off. The intake seats on cyl 8 got loose. The markings on piston top are really nothing, no depth to them. I was lucky.
I think a valve job is all I need.

 

Amaaaazing amazing work Steve! Really. And challenging I know! Good stuff.

Hmm. Just thinking out loud, thinking if it were me... Heads for these cars are readily available. Those two indentations on the top O the cylinder, and how many times they actually hit those valves and seats MAY have done more damage than one might expect... Shockwaves thru the head.

I think I would get a new head,,, have it worked and the valves lapped out, new valve seals etc and go that way. With the $$$ you would spend on having that head rebuilt, not really knowing the true (near microscopic) extent of the damage (maybe not being able to find a mechanic who could tell ya) you could have a non knocked around head brought to near new...?

Damn dude. Ya fought the good fight!
That's sumpthin right there!
Good show

 

Can you post a picture of a set of valves and seats that are in place? If you don't mind. I would be interested in seeing the difference between the two.

 

here you go

 

Is it usually cyl 8 that has this issue or just coincidence that the only ones I read about are Cyl 8?

 

Thanks Steve.
Mine was cylinder 8, as well... Didn't know it was a thing

 

Steve.

lm in exactly the same boat as you.

The biggest problem i have with re using the same head is if those seats, not one but two have dropped its 99% likely the car got too hot at some point in its life. My money would be on at some point more will drop.

The reality is you can buy a good used head for way less than a shop (here) could fix those two, as theres bound to be welding and machining involved, let alone do the rest.

Something to think about if you go that route; Buy the complete head, dont try and save a bit by using your cams it can take forever to shim them to a different cam and sods law says you will need shims.

l ended up buying; 1 x good used head, 1 x top end gasket set. 1 x timing chain set (inc chains x 4, guides x 4, tensioners x 4, water pump, gaskets & 4 sprockets) 1 x full set new head bolts, 1 x new crank bolt, 1 x new belt. l belive this is the bare minimum, and im as cheap as yer quintessential European great grandparents.

Best of luck with the build, i will be right behind you, or slightly ahead depending on the shenanigan's of Canada Post

 

markel
Did you have the head checked out? How?
steve

 

Steve.

lt hasn't arrived yet, when i does i will put it on a piece of glass i have and have a poke around with a feeler gauge of a yet to be decided thickness. l dont expect problems as it comes from a reputable seller. l will PM you his details.

 

both heads off with all the other stuff

 

here is how socket fits so there is no wobble and rounding of bolt head

 

i use pvc pipe to hold tappets in place. You cannnot mix them if you plan to put the head back on. I will get estimates for the heads on Monday.

 

Where do I find a workshop manual with all the specs for further disassembly and rebuild? The JTIS stops after head removal.