I believe you may be right about the ring, but I'm afraid the engine isn't coming out! I've confirmed that the leak goes into the sump. That takes care of that, the head (and tensioner) can stay put!

Thank you to everyone that responded and offered advice, it is much appreciated.

Cheers!

 

Worth trying a bodge maybe? Warm her up, squirt some stuff down the bore that might loosen the ring, let it stand for a day or two, give her a blast and hope for the best? Run that cylinder without the plug and with the injector disconnected for a little while first, to blow out any residual stuff. Someone might know a good product to try, possibly injector cleaner? I have never done it, just an unproven idea ready to be shot down.
Greg

 

Could be a broken ring? Might be cheaper and easier to find a good used engine?

 

She's a non-smoker, low mileage, the engine and the car will stay. If it does turn out to be a broken ring I'll save up to rebuild the engine.

 

Good for you, but honestly, if it is an unstickable/broken ring, "all" you will need to do is get the engine out, pull the one head off and the sump/sandwich tray, crank windage tray shield thingy, unbolt that cylinder's conrod big end, and carefully push out the cylinder. If the liner is shot, get a s/h one, and reassemble with new rings and a head gasket. Everything else will be fine as is for another 150,000 miles!
Some work, yes, but not a huge expense. And while the engine is out you can do a good cleanup, fix any cam cover leaks etc etc, renew the oil pickup pipes O rings, all the belts and water hoses, replace any iffy wires. All good fun not expensive and dead easy with the engine out!
Greg

 

Thanks Greg, if I decide to go that route I'll definitely post, glad it isn't too much of a task, thanks!

 

I've taken many heads off without de tensioning the chain. But you might break it either way.
Leave it alone !!

 

Many thanks melhookv12, great to know!!

 

Taking heads off without taking tension off isn't the problem. Its putting the cam sprockets back in place AND in the correct cam timing position is the problem. Along with the getting the heads off to start with. Don't underestimate doing a valve job on a Jag V12. Its no wonder that so many of these V12 powered cars wind up being parts cars.

 

Super has a point here, I've no experience of trying, but I'm inclined to agree.

Which reminds me, thank you for your advice on freeing up the rings, worked well!

 

I agree. I was taught by an old fashioned master. He showed me that the cam bolts will only go in when the timing is spot on. One of the 4 holes is actually smaller than the others. You should be able to screw ALL the bolts in without any resistance.

 

if the ring has freed up, how is compression now?

 

Try pouring Seafoam or Marvel Mystery Oil in to the cylinder with no compression let it sit for a few days then take the spark plug back out crank the engine to get all the oil or seafoam out so you don't bend a rod, (It will shoot oil pretty far so be ready with rags or something) then start it and see if it burns off whatever carbon was in the cylinder making the ring stick. I know it worked on an old MGB I had an a TR7.

 

Ronbos, the ring is still stuck, so I'm gonna go the carby cleaner route, but it is certainly better, but not right, yet.

89xjsrules, thanks for the advice, I hear both products work well, but I don't know about availability in my part of the world. I might look around.

 

Another product you may consider is PB Blaster. Not sure is is available in Durban, but have used it on a couple of engines with great success.

 

[QUOTE=NathanDD6;1420000]Ronbos, the ring is still stuck, so I'm gonna go the carby cleaner route, but it is certainly better, but not right, yet.QUOTE]

Continue the treatment with something or other (I am a great believer in a 50/50 mix of ATF and acetone by the way). Just keep at it and let it soak for quite a while. Then, having changed the oil, I reckon if you start the engine, warm it up and rev it a bit, drive it a bit if you can, even just round the yard, so it sees some load, and it will free itself.
Greg

 

All those voodoo mixes sound good, I'm a great believer in 50-50 diesel fuel and mystery oil, and soak for few days!

Although the acetone should really do well, it's a powerful solvent!

So far nobody has mentioned why the ring stuck in the 1st place, some times water or condensation has settled in the groove!(gasket,rain,etc)

Like Greg mentioned load it up ,get it HOT, luck may expand the aluminum piston and free the rings up!!

 

Thanks for the replies, like i say I've driven her 1000km's before I figured it was more than a bad injector. Stuck ring I'm sure, got it soaking in carb cleaner as I type this. The car did sit for a long time (a year without running before I got her) and we also have the nasty problem of ethanol in our fuels, which I'm going with for the cause.

 

Did the ring(s) ever free up?

 

Came a lot better, believe it or not I've still got a sliiiight miss, admittedly I should be treating it a bit more, plus one for ATF though