No 6 plug is very very stiff but started to undo a fraction of a turn.

My mechanical feel for when bolts are about to sheer suggests I am at an oh feck moment.

So I am working it fraction back on forth but not seem to budge.

Going to squirt some wd40 and see if that loosens it up.

Gut feeling looking at plug 5 is that the plug penetrates the chamber by 5 mm or so. Plug 5 was clean thread from hex down to this area then appears almost quite corroded onwards to tip. Cylinder 6 has been misfiring a little on start so it might be in worse condition inside the chamber so corrosion and deposits on the threads there might be what is causing the problem.

So next thought is warm engine a bit or lots? Not sure if they remove better with cold engine.

Any advice welcome Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

Last edited by SMUTT on 25th Sep 2015 7:46pm. Edited 1 time in total

don't rely on wd40 -it's too general purpose, and its really a water displacer...get some gt85 or research for better penetrating fluid/spray. it really is worth doing this carefully with the right stuff. overnight soaking... sounds like if you are moving it just a tiny amount, and its feeling like its moving, that its got rust, or carbon build up on the bottom, and this could break up completely, and/or score the threads when coming out. if this is suspected, order a plug thread tap on ebay, to gently rethread the hole, in case you cross thread the new plug. (use grease of cutting compound to stop swarf dropping in.. they are about £7 assuming it comes out good. often you can get a little tighter on the plug turning, and then back just a tiny bit. to get the thread moving, and fluid working its way through..i did mine, some were a bit tight, but I made sure I had a good angle of 'force' with a 10 inch breaker bar/tommy bar... in case it slips and force is applied too steeply and causes plug to bend/snap.
you really don't need to do them up tight. use a tiny bit of grease too. if you had oil in the plug wells, (I did) you need to soak that up, and/or rinse it with petrol, and again soak up, so that the gt85 is at the point it needs to be. can be rinsed out with the straw tip etc.
engine will smoke for a half minute on start up...

Good luck!
I was fixing a small leak on a thermostat gasket on a V6 Granada Ghia we used to have, got two of the 3 bolts out but the third one was one of those 'this feels a bit ti... oh !' moments!

Ended up having to drill the bolt which had sheared off flush with the inlet manifold, using my dads screw extractors, snapped that off as well!

Ended up having to get an inlet manifold from a scrappers, which was not easy as it was between Christmas and New Year, hence why any mechanical work on cars is done now by a garage!!

If in the very unlikely event that you have stripped the cylinder head thread all is not lost.

I stripped a plug thread on my old 3.9L petrol RR, I took the head off and Heli-coiled it.
Occasionally the Heli-coil came out with the spark plug when I changed them but just screwed everything back in.
It was like that for about 6 years till I sold it with no problems.

Peter

Thank you Gentlemen for your time ...

@JohnBoy
- I was hoping you would drop by on this subject - so glad you made it to the party ... and first inline as well. Thank you for your sound advice on WD40 before I went and fubared it all. Oddly although I had used WD40 for years in such cases I never had success with it but since the item eventually was freed by say Hammer, Chisel, Drill, Sawing I also never researched an alternative. Often when freed the nut was dry inside - WD40 clearly never penetrated it.

So now I have done research and found "PlusGas" - excellent reviews on Amazon, with a few people using it in my situation when their local garage gave up and they freed the plug themselves. Totally agree a job like this requires steady patience - the worst happens when you get tired and frustrated and think one last push on the spanner will solve it

@PaulTyler
- had similar experience with Ford Cortina on a Cold winter Sunday night - needed the car ready for Monday morning.

@Strider
- thank you for the helicoil tip - never used them before and hopefully if I take my time (SWMBO makes me stop for tea breaks) I won't need them - would not really fancy trying to helicoil these so deep inside the head and poor access.

So it is off to Amazon to purchase PlusGas. Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

try putting the rest of the plugs back in and running the engine up to temperature and and then taking the plug it usually frees them up on most engines L322 2008 vogue
R53 Cooper S Works tuned beyond the works SOLD
R33 Nissan Skyline in rebuild 400bhp atw

Thanks Ivor. I had warmed up previous cars but due to conflicting Internet info I found suggestions that the bmw alloy was better left cold.

Not wanting to reach the oh feck moment, I instead reached for the kettle, made a cup of tea, had a think and consulted the forum.

Years of experiencing many oh feck moments finally teaches you that tea is better than tears.

Thanks for the advice Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

Hi SMUTT haven't tried it myself, but some people I heard of have used coca cola, soak overnight, mechanic did it on my sons audi when he couldn't get the injectors out. It worked.

I use the cup of tea method when removing the bottom off of skyline engines apply pressure have tea come back apply more pressure have tea and repeat until it comes off ,theres also a spray called shock and unlock it's basically a freezing spray same principle as heat except reversed L322 2008 vogue
R53 Cooper S Works tuned beyond the works SOLD
R33 Nissan Skyline in rebuild 400bhp atw

@gregdav - thank you - I had heard stories of people getting old engines that had sat rusting, to work using coke to free them - basically removed spark plugs and poured coke in the cylinders - left for a while, and it freed them up.

Plusgas arrived today - going out to start with it soon - oooooh exciting.

I also read many positive reviews concerning 50/50 mix Acetone and ATF - prbably best mixed in metal container and not allowed to touch anything but the metal you wish freeing but it eats through rust like nothing else apparently. I have Acetone already so might mix some up for freeing up the notorious Front Damper lower bolts. Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

@Ivor - thanks for your input. I have a theory similar to that that the tiny twisting movement you induce needs time to work its way through the whole fixing. By applying too much movement in one go leads to - well hell sometimes! Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

50/50mix of diesel and ATF is an excellent releasing agent

@47p2 - thanks for the input.

SUCCESS!

Poured "Plus Gas" (comes in Aerosol and 3in1 type oil can with spout) down the plug well and soaked overnight.

Large Breaker bar and Plug socket used to ease the plug back and forth. Perhaps 10 times in a session then leave for an hour or so. A little more was gained each visit. You just can't rush a job like this. The stakes are too high (cyclinder head off )

So over the course of a coupe of days eventually got the plug out this afternoon. Looks like it has been in there for years - perhaps previous service attempts gave up as it is different to adjacent plugs - they changed the others and probably thought uh-oh I ain't touching that one.

I used a large breaker bar, not to apply huge force, but to give me more accurate control for keeping the socket and extension bar square on to the plug hex. I swung it using one finger tip while holding the pivot end connected to the extension bar firmly in place with the other hand.

regular squirts of Plus Gas, regular rest breaks finally got the result. I am so happy.

As for the plug that came out it was a wonder it ever sparked at all. BMW Bosch marked one could even have been factory fitted. Engine much smoother now on tick over

Special Thanks to JohnBoyAirey for pointing out the error of my ways and diverting me from WD40 and possible path to hell. Howard
____________________________________________________
2002 4.4 V8 LPG Tartarini
Have RSW AllComms in Cheshire J17 M6 - happy to help.
*Gone: Classic Vogue SE Auto V8 3.9

well done that man....
just a follow up, WD40..... the WD is 'Water Displacer' i think there is a rumour, that its mainly fish oil... but here.. https://en.wikipedia.org/wiki/WD-40 parhaps not.
i use it, here and there, but i have a can of some funny trade name stuff, that works, like plusgas.


often, with a seized bolt/nut, a few sprays and soaks, works, if not, then you can try sharp hammer blows, and resoaks, and finally localised high heat. all these are not really possible on spark plugs. so patience and afore-thought is the way forward. in all such instances, back and forth, is the way.

Well done Howard, glad you got that out OK...  Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-