Stuck sparkplugs - How to loosen?

P

Paxe

New Member
The sparkplugs on my P6 V8 are stuck, and I´m afraid of damaging the engine if I use to much force to loosen them. Is there a danger of cracking the material around the hole where the plug goes in or of breaking the plug in two, making it impossible to remove it? Any useful ideas on how to loosen the plugs?
 
Yes the plugs can break in the head, but you won't know until you try to get them out. Also the plug, if it does come out can bring out all the thread from the head with it. If this happens and you can get to the hole, with care they can be helicoiled in-situ. You could try filling the recess in the head with a good penetrating oil before you try removing them, but at the end of the day you won't know what's going to happen until you actually do it. You may find when you really give it some grunt they just come out, or someone may have crossthreaded them in the past and you have problems.
 
Paxe,
Any success yet? Are they all tight? If they haven`t seen daylight for a long time then they will normally be pretty stubborn anyway. I would concentrate on just the one, and as others have mentioned you won`t really know what will happen until you try. Use a good quality plug tool, one that fits well, and give it some welly!
All the best, Drew ???
 
Further to all the above I should add that the plugs that tend to give most problems of this type of thing are the taper seat variety as fitted to the Ford Pinto and BL O series, not plugs with washers as fitted to the P6. Also P6 V8 heads have short reach plugs so less thread to seize (SD1 heads have long reach plugs)
I have had heads that have cracked between the water jacket and the plug hole and those REALLY seize in (but we won't mention that!)
 
When I had a really stubborn rear plug on my V8,it was nigh on impossible to get a good position for leverage with a std plug socket and wrench :(
I used a very good strong,tight fitting socket with a breaker bar,got my brother to hold it in position while I slipped the 5ft long handle off my trolley jack onto the breaker bar to give HUGE!!! leverage :O and with very little effort,and relief it went, CRACK!! as the seal was released,and it could almost be undone by hand after that,
once its out clean the thread on a plug,use plenty of wd40 and screw the plug in and out by hand to clean the tread as good as you can.
:p good luck!!
 
I would agree, most of them come out, sometimes shattering the porcelain as they do, it's just a matter of having the bottle to really give them some grunt, the longer the bar the better! Go for it!
 
What about putting loads of wd40 around the plug seat then run the engine til warm. with the plugs warm try and get them and see if this helps to make them budge.


Colin
 
Hot aluminium and stuck bolts will result in stripped threads so not recommended. Most manuals tell you not to do this

Using a breaker bar on a spark plug is something I've never had to do - a brave man indeed !
 
The use of a long breaker bar won't mean you're any more likely to snap the plug.It will either break or it won't, and the effort to do either won't be any different regardless of how long the bar is that you are using.
 
Probably better to do when cold as suggested, but worth spraying the wd down, then run the engine and allow it to cool (probably next) - a couple of heat-cool cycles will help the wd to work its way in.
 
Thanks to all for useful tips. I´ll have a go as soon as my garage thaws. It´s freezing outside right now. Will post results as soon as I´ve got any.

Thanks again
 
from what people say, doing it when it is really cold is the best way.

put wd40 or even better specail penetrating oil overnight.

sometimes trying to do them up a tiny bit cracks the seal, not sure I'd do that for risk of stripping the threads.

a s mentioned, a longer lever allows you to put a lot of force in a very controlled manner - the longer lever menas you need to move it less then with a shorter lever.

worst case you damage the heads; I've got two pairs of p6 heads, ready to fit for little money (sorry don't mean to advertise but if you bugger up, you know there is a solution) - pfew v8 comapanins e.g. Rinmmer are not interested in the older heads.

clean up the threads by malking a longitudinal cut oin an old spark plug thread - the slots picks up garbabe as you do it up.

finally Good luck.
 
I hope he is not!!!! BUT??? after 2 yrs,is he still trying to get them out!!!??? :roll:
Could be the record for a plug change though!!
 
Yes, I would be interested aswell! I'm trying to undo my 4-cylinder's plugs after at least 31 years in situ! (Not running in all that time).

I put WD40 in the recesses about 2 weeks ago, & haven't dared to go back to it yet :LOL:

Phil.
 
WD40 No good, you can't beat the old Duck Oil, wheather you can buy it these days,I don't know, but I always used it, when the Ambulace workshop closed and they put the work out to the Main Ford dealers in Swansea ( the worst move they ever done ) now after nine years the are thinking of going back to In House again, I took two cans of Duck Oil with me, and all that is left now is about 2" in the bottom of the bottle, and to think I left about two dozen in the store room. Anyway I've had my say now!!!!
Julian.
 
JULIAN BEST said:
WD40 No good, you can't beat the old Duck Oil, wheather you can buy it these days,I don't know, but I always used it, when the Ambulace workshop closed and they put the work out to the Main Ford dealers in Swansea ( the worst move they ever done ) now after nine years the are thinking of going back to In House again, I took two cans of Duck Oil with me, and all that is left now is about 2" in the bottom of the bottle, and to think I left about two dozen in the store room. Anyway I've had my say now!!!!
Julian.
Click to expand...
Sorry to have put that " No good" bit in, WD40 is a good product, but I have always found Duck Oil to be a better product, and there again my father used to say there is no better releasing fluid than paraffin, it will creep in everywhere ! I'm posting this now because I've only just read what I posted earlier, and realised that it wasn't a fair comment to make.
Julian.
 
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