Spark plug not tightening or loosening just spinning

So I decided to change my spark plugs, and the first 5 were just fine, with the last one (closest to firewall on passenger side) I got it undone fine, put the new one in and tightened it fine, then when I went to put the black bit back over it it wouldn't go all the way on, so it took it off and put the socket over the spark plug again to find it was spinning with my hand in either direction but not getting tighter or looser. I did not over tighten (if anything I do all bolts under tight just to be cautious, always so theyre firm but no further). I have googled it and every thread says the plug/area it screws into is threaded and that the engine needs pulling apart to fix it. Before I part my car out or sell it as is because I cannot afford to get it fixed and don't have the time knowledge or money to do it myself is there anything else that could cause this/I can try to fix that doesn't involve pulling the engine apart?

 

I don't know how you could have done that if you have only done what you describe.

you need to check that the thread on the old plug is OK.
take the new plug out.
check that nothing has fallen now there making is seem like you were screwing the plug in.

when you put the new plug it did you have any trouble turning it or was it easy to turn?

worst case scenario you might need a new head.. can be done with the engine in the car but better off out and might as well do timing belt and water pump.

 

it is possible to helicoil for plugs I would hate to do it insitu though

 

Thread on old plug is fine. Can't get new plug out, it just turns in either direction but seems to get neither tighter nor looser, Was easy to turn new plug in, exactly the same as all the others.

And yeah, have no idea how it could be threaded from just what I did either as I was being careful not to let anything like that happen. That is why I am hoping there is another possibility for why it could be doing this.

 

From your description...

....it sounds like you have cross threaded the plug.
As the head is made of aluminium & the thread on the spark plug is steel, the spark plug has cut another thread into the cylinder head when you've tightened it, causing the thread to be damaged.
When you have attempted to tighten/remove the spark plug, the thread has stripped.
The thread can be repaired using a "Helicoil", however part of the process requires re tapping the thread with a larger tap & inserting the helicoil insert.
No big deal except when re tapping the new thread, aluminium shavings will drop into the cylinder & end up on top of the piston.
Also, the helicoil insert has a piece of metal used to drive the insert into position, this piece of metal has to be broken off the insert & there is a probability this piece of metal could/will end up in the cylinder with the aluminium shavings.
Hence the requirement to remove the cylinder head.

 

A mobile thread repair guy like the link below is what you will need, they say they do spark plug threads, how they clean out the swarfs I don't know, maybe a vacuum cleaner. Find someone in your area, let us know how it goes and how much.

http://www.mobilethreadrepair.com.au/

 

couple of things spring to mind straight away.......

1/
have you had a look down the plug hole ????
sparkplug sockets have a rubber grommet inside them to help in 'holding the sparkplug, this grommet can with age or excessive use become dislodged and will either fall out and become a hidden item somewhere in you shed or will stay with the plug you've just fitted or removed.....
If the grommet is sitting on that plug there's a good chance the socket wont engage the nut and therefore wont turn.....
Fingers crossed for you .....



2/
have you started the engine since the issue ????
if the thread is that shagged there's a likely-hood it will shoot the plug straight out..... usually denting the bonnet on its exiting trajectory... a blanket thrown over the area will stop the dent .... don't ask how I know this ....

2ndly..... some cylinder pressure from a running engine will assist in getting a stripped plug out, sometimes its a pressure thing, other times it may be from a small carbon deposit or even the engine heat can help...... sometimes....




don't panic yet, all is not lost......
a helicoil can be fitted to replace the damaged thread without having to remove the head or engine, you simply use compressed air through the inlet side (plenum) to constantly blow air into the cylinder thus keeping it clean and free of debris from the helicoiling......
( yes you'll need to rock the engine around so that the inlet valves are open before doing this )

good luck !!!!

 

Was in a rush to get to work because I was trying to get them done before nightshift tonight but when I had a look down there did seem to be a tiny bit of something black at the base of the spark plug sticking up a little, was going to have a closer look tomorrow, but due to the location of this particular spark plug its hard to see down, hard to get into, hard to everything lol, had to use 3 extenders on my socket thing just to get in there.

I thought about it but I heard this isn't too good for the engine, can shoot it out and damage the car (didn't think of the blanket thing) and 2 figured fuel pouring out the cylinder probably wasn't a good thing either. Also I heard that if it is threaded there may be some shreds of metal in the cylinder already and starting it up could damage it?

Will have a look in WA for a similar service and give them a call tomorrow if i'm not lucky enough that its just the rubber grommet badzx mentioned.

Thanks for the responces btw.

 

Use the camera on your phone. Set it to Macro and turn Flash on then you can see in the hole. You can also zoom in on the picture to see the inside easier.

 

What if he can't fit the Zed into the Phone box?:br:

 

There's a tool for this. Its 50 bucks, slides into the cylinder then expands then you turn and pull to cut a new thread. All shavings stay outside. VEK TOOL had the only one I've seen.

 

This is worth a try!

You should buy syntax a slab for this info!

POWERBUILT 14mm Back-Tap Spark Plug Thread Repair Tool

$49.01 inc GST In stock

-The Back-Tap 's patented collapsible design allows it to be placed through the spark plug hole and into the chamber.
A mandrel is then drawn back, expanding the tool 's threaded area and threading into the clean threads at the bottom of the spark plug hole.
The Back-tap repairs the damaged threads as it is drawn up through the spark plug hole, bringing debris and metal filings with it.

NO Need to pull cylinder head!
NO Metal fillings in engine!
NO Coil insert needed!

 

That's the one, not sure how well it'll work but its your best/cheapest bet.
http://www.vektools.com.au/powerbuilt-hand-tools/powerbuilt-14mm-backtap-spark-plug-thread-repair-tool-p-6182.html

 

I've got my money on this, If you threaded it you'd know it, or even if it was already damaged by a previous owner you should feel it get slightly tight then loose.

Its the last plug you played with so fingers crossed the socket left the grommet behind.

 

If you could find that tool Syntax knows of you'll be away.

If your not confident you've collected all the shavings, a good engine flush of Diesel fuel will help in getting the shavings out.

You'd be draining your oilpan of it's initial oil and then keeping an eye on your oildrain bucket for a bit.

Douse that particular cylinder for shavings. Then unplug your Coils !!! and prepare to start winding the engine over.
Wind your engine over and over whilst dousing the cylinder further and emptying the oil bucket as you go.
When you drain the oil bucket ,. you'll be able to inspect the sludge content for the lesser and lesser sludge content as you go.
And with each dousing/dilution , you'll come closer to the result of having mostly diesel come out the sump drain.

 

I don't recommend this, I am yet to see a sludged up VG30DE.
Replacing the oil with diesel will just scratch things up, I don't even want to think of how the lifters would feel about this...

Best bet would be to ensure the cylinder is dry so the shavings don't stick to anything and can freely blow out, plenum off, charged air running down one of the intake valves.

The tiny shavings that will come off could only potentially hurt the exhaust valve bed, everything else is far harder than it..

Also cant see the point in dousing the entire engine, nothing would get past the rings.....

 

Something has fallen into the plug galley, on old piece of hose or some other crap doing as badzx says, not allowing you to get the socket back on the plug properly.

In the remote chance that you have actually stripped it, that tool won't work because the plugs are too deep in the head. Only option is a normal tap. And don't even bother stressing about the debris in the cylinder, put the piston at tdc and tape a small hose to the vacuum, suck out what you can and start it up. A few filings won't do shit.

As far as flushing it with diesel, that's going to do nothing to get the filings out of the cylinder, may as well roll the car onto its roof and shake it a few times...

 

From playing with it today I beleive this to be the case. Because its so deep though I can't seem to get enough light in there to see what though, so I have no idea how to get this spark plug out (have tried plying it out with a coathanger and a screwdriver with no luck). I'm not sure if I should try blowing it out as suggested because this is the spark plug that is directly under the black thing that goes over the plenum, which means that it will likely blow into that and damage it. Also if it is partially threaded in I'm guessing blowing it out will damage the threads its already on (or just won't work as it will be held in there too tight).

Open to ideas, or anyone with experience prying things out from small places in WA popping by to help if theyre free.

 

Magnetic pickup rod?

 

Would want to be a damn strong magnet if I can't pry it out with anything