hey guys,
my brother just got an '85 240 sedan that I am fixing up a bit for him.. I went to change the plugs and the first one broke off with hardly any force put into it. all of the threads and whatever is between is still threaded in. the plug broke right underneath the socket head.
Has anyone dealt with one of these before? I have no idea how to get the rest out! any tips at all would be great, Thanks!

One trick old bicycle mechanics have used for years with stuck steel/alloy components (like when a seat post is stuck in the seat tube) is to pour a little ammonia on the joint. It seems to dissolve the aluminum oxides that form at the steel-alloy junction. Anybody try this with stuck plugs?

The standard plugs, lasting perhaps 30k miles, are usually changed often enough to keep this from happening. The long-life platinum plugs can experience seizing problems because they sit in the head so long. To prevent this, use a quality nickel-based antiseize on the plug threads and install with about 40% less torque to account for the lubricity of the anti-seize. Every 40k miles, loosen and re-torque the plugs to make sure they aren't seized.

Yank the head off. If it has never been off before, it needs the head gasket replaced anyways. Don't fight the busted piece in situ. The threads are obviously tight enough to have broken the sparkplug shell, and there is little you can do with the remainder. On the bench it will be an easy job for a skilled machinist.

Wow that's ugly. I think you're going to need to knock out the center and remove the shell with an EZ-out type of device. This is a tool like a drill bit, designed to bite into the center of a hollow threaded piece like you've got there. May be called a "pipe nipple extractor". MAde in various sizes, so you'll need to check out the diameter you need. I assume that the center is about the same diameter as the shell you see when you look into the electrode end of an intact spark plug.

If there's still a center in it, that will have to get out of the way- if you can do it without dropping much into the cylinder, so much the better. I doubt you can, so cleanup will have to come later. There may be ceramic as well as steel or copper electrode pieces.

Once it's just a hollow shell in there, the Ez-out is driven in, till it bites, and then unscrewed. You probably want to apply heat to the area with a torch- propane would be fine.

Hopefully the piece will unscrew and the threads will be just fine. If the threads need repair as well, it's probably just as well to take the head off the car and take it to a machine shop. If you do get it out and threads are good, I would rig up some kind of a tube adapted to a shop vacuum, and push it in there trying to get every last little bit of grit, metal, ceramic and chips out of the cylinder. Anything leftover becomes a battering ram, destroying your head, valves, and piston top.

Good luck with this, I don't envy you with the work ahead. Any good hardware store will know what you're talking about when you go get the EZ-out extractor.
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::: Rob Bareiss, New London CT ::: 92 244 M47 211K ::: 90 745GL M47 273K ::: 88 245DL AW70 190K ::: 84 242DL Project ::: 70 VW Bus ::: 70 VW Pickup Project ::: 71 VW Notchback :::

Aye Roll:

Excellent advice you have provided here! One additional recommendation though, assuming the center electrode (ceramic insulator) is out. Use some wheel bearing grease and lube up a roughly 4 to 6 foot length of yarn. Then feed it into the sparkplug hole.

Now extract the plug by whatever means, and when you are done, fish out the greasy yarn with a hook. The grease should "grab onto" any and all shavings, so as you pull out the yarn, all the bad news should go with it. You can follow up with a shop vac and tube just to make sure.

The only plug I have ever had snap like this was an Autolite in an aluminium head B230F. Since they black anodize their plugs and don't nickel plate them, they gall via galvanic reaction to the aluminium head. Very very ugly job. I tried to get it out for four hours and finally gave up. Took the head off, took it to the machine shop, and $25 later, the busted plug was out and the threads were chased.

I've used never sieze on plug threads ever since and shy away from autolite plugs like the black plague they really are!

jorrell
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92 245 245K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently in pieces

This can be a tough problem. What I would try first is a thorough soaking with PB Blaster, letting it sit for a day or two, then soaking it again. After this treatment, get the biggest straight screwdriver you can find (you said it was the first plug that broke, so I'm assuming it's the one at the front of the engine, giving you reasonable access to work) and hammer it into the remainder of the plug (in this case assuming that only the threaded part is stuck in the head, and the insulator came out wth the part that broke off) You want to wedge the screwdriver in solidly in place but not expand the plug part too much. the screwdriver should have either a square shank or a hex, to which a wrench can be applied. If you are lucky, it will unscrew without too much difficulty.

I don't recommend an easy-out, because if it breaks off, your problem gets a lot worse. The screwdriver is less likely to break (if it's a decent one) and easier to remove if it does.

What kind of plug was it? The only ones I've ever seen do this are Champions. I avoid them for this and other reasons. Bosch Copper and NGK are good choices for Volvos.

Soak all the other plugs with PB Blaster while you're at it, to help avoid a repeat.

they were Bosch Super plugs. I was very suprised too, but the car had been sitting for quite a while and hadn't had the plugs changed for a very long time according to the previous owner *sigh*
i'll try this screwdriver method first....before breaking out the whole center of the plug... then move from there. Thanks again everyone and I'll yet you all know what worked!

It sounds like the shell fractured just beow the hex. Most that break (usually Champions) fail just below the gasket from a forcing against siezed threads.

Did it loosen at all before breaking? If the ceramic is gone, then you can use a tool called "E-Z-out". It is a tapered square shank made to extract broken bolts with sharp edges that dig in when turning to the left.

If the gasket is not seated against the head, drizzle some 3-in-1 or ATF on the plug as a penetrant to lubricate the threads. Dont muck it up with WD-40 (which is not a penetrant). You may get lucky in removing the remains if you work carefully with what's left.

Hi!
Is those corners all out in the plug? If so, you can weld by MIG a suitable nut to the rest of plug. The heat helps, and it probably comes out easily. I had done it few times. Its sad, that people don`t use ANY lubrication, when they installed spark plugs. Copper past is good to use, then you don`t need to repair holes whith Helicoil. Hope you get it out, whithout damages. BTW: Use moment wrengh (250NM). Good Luck.

Yrs: WEBERMAN

well if you could do it very carefully, maybe super-gluing a wood dowel to the remnants of the spark plug, without getting any on the threads.

Pull the head and take it out from the back side This is a three hour job
Then when installing the plugs use anti-seze
Rodney