Damn, I Broke a Sparkplug

A month ago I got a 94 Caprice wagon with the LT1 engine. Haven't had time to mess with it much, but just before dark tonight I decided to pull a spark plug to determine if I should buy a set tomorrow. The plug easily turned then was real loose immediately. In my socket was the plug including the positive electrode and still in the head is the threaded portion. The nut portion of the plug is still attached to the porclain part of the plug and is sitting beside me now.
I've changed 100s of plugs in my life and have never had this happen before. What's the best wisdom to remove the threaded portion? My first thoughts are some type of rust solvent and an EZ out. If this is the best method, should the engine be warmed up at all? BTW, it is the #1 plug.
Thanks,
Eric Pederson
Fort Ransom, ND

I do not know the answer, but at least it was not the #6 or 7 plug. Be careful using an easyout, they are extremely brittle, and hard. If it breaks, you will be screwed.

i have the solution,. but it takes some skill,.
better to PM a ph# its easier explained by phone,.
basics are a 30" good quality 1/4 drive extension and some 1/4" square carbon tool steel,.
i,ve did six on a car one time,.2 just recently,.

Nick
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I HATE Easyouts for the very reason you mentioned. I have had them break, usually in the off centered holes I've tried to drill. From a Google search, most people have had luck with the Easyouts. I'm thinking since the nut portion is now gone, the tension on the threads is relieved and it MAY back out easier than I'm worried about.
From Google, one guy was able to remove the threads by tapping a flat end screw driver into what was remaining of the plug then turning.
Now I'm worried about removing the remaining seven plugs.
Wish me luck!
Eric Pederson
Fort Ransom, ND

That's amazing and scary. I've never seen a plug do that. What causes it, rust???

phantom 309 wrote:

i have the solution,. but it takes some skill,.
better to PM a ph# its easier explained by phone,

I would put money on Nick having the solution.

Tom C.

I over torque one on my first vehicle and got it out by tapping a slotted screwdriver into it, but then again I had just put it in, Talk to Nick is my best advice if the screwdriver doesnt get it

If I am correct, the plugs have a tapered seat and if you put them in too tight, they will be difficult at best to remove. Get a drill that is the same size as the diameter of the trough of the threads, and drill enough to cut the tapered part of the plug off. The threads will not have the tension of the tapered seat, and should be easier to remove with any screw removal tool.

I also saw some screw removal tools that are similar to easyouts, but have two squared flutes. they are left hand cutting so would likely remove the plug. I do not remember where I saw them.

I wouldn't advise anyone to drill into an area where you don't want chips to fall. The hole in the spark plug shell is pretty big, meaning that the proper size easyout would be pretty stout. I'd at least (gently) try one first, if it were me.
EDIT: Just to add here for Eric: I have also broken easyouts in holes, but they were always the little, skinny 'frail' ones. Your spark plug hole has got to be at least 3/8" in diameter. That should allow for one of the big, stout easyouts. BTW, the trick with easyouts is to try your best to apply a 'circular' motion without any side pressure. This can be done by applying some upward pressure on the pivot end of the wrench while pushing down on the handle (or vice-versa if you have the wrench on the other side). It's a 'learned' skill. It's why, whenever possible, you should use the T-bar handle on easyouts to minimize side thrust.

SUCCESS!!!
Waiting for the electrician for my garage project, so I finally decided to tackle the threads left in the head on my Caprice. I basically followed Nick's suggestions. I didn't know where I could find any 1/4" tool steel so I used a EZ Out. Going through the fender well I attached m longest extension to the EZ Out and used my large tap handle on the square end of the extension. Took me about three attempts, but the threads busted loose. I'm one happy guy tonight, but now I'm wondering how I should tackle the next seven plugs so that I minimize the chance that they break? Open to all suggestions.
Thanks for the advice,
Eric Pederson[img][/img]

The only thing I could see that might matter is applying the same, 'balanced', circular torque to the plugs. This will minimize any thread bind. It probably wouldn't hurt to spray some penetrating oil on the threads a day or two before. Good luck.

What kind of plugs are they? I had NGKs in my boat that broke the same way. Now I replace them every other season.
I was afraid of metal particulate falling in the cylinder. I pulled the head and taped the sparkplug screwed a bolt in it.
Then I welded the bolt to the sparkplug. It was realy frozen in the head. The rust was intense. I first tried an easy out and it just snaped. I had to weld a huge bead on the easy out so I could grab it.

Thanks
Randy

I,glad it worked out,.
The reason i say to use carbon tool steel, is because its a hell of a lot tougher than an easy out,.easy outs by my experience are brittle,.and really good ones cost large money,. your case hardened cheapie from china is good for brass fittings and not much else,.
As jimbeau said the tap handle on the backwards facing extension is the best over a wrench, as he said it gives the proper twistng motion,.
Not too sure i like Freds idea with the drill,.. the chips can be overcome with a slow drill and plenty of wheel bearing grease to catch chips,.and crank the motor on the starter and it'll blow the cylinder clean,. but the problem lies with the lack of room,.i have to unpin the motor mount sometimes and roll the motor up on the side i need to mig broken exhaust studs,. and there's barely enough room for the mig handle,.let alone a drill,.
See my above post,. If one breaks get ready for the other 7,.
get yourself a decent set of oven mitts, cut the ends off them just enough for your fingers to find stuff,.Then drive the car fairly hard,. bring it in hot and then pull the plugs,.

Nick

On boats, it's always smart to use anti-seize compound on threads wherever possible, because of rust.

+1 on staying away from the easy outs. More of a pita than a help in my experience (see my thread on the thermostat debacle)

I soaked them down with pb for a couple of days, it wont hurt anything

The plugs in the engine are Champions, but I can't blame them. Everything in the engine compartment is fairly corroded. Surprisingly the body is pretty decent. Going to go through an ocean of rust bomb before I try the other plugs. At least I'm learning something.
Eric

If you are willing to take the time, and use penetrating oil, you can get most any threaded piece loose. WD-40 is excellent for this use, because it contains an evaporating penetrant AND a heavier oil that does not evaporate. The thing to remember is to shake the can before every squirt; otherwise, after a short time, you have emptied the can of all of the oil, and all that is left is penetrant. A variable speed impact wrench is also helpful, because it 'hammers' or shocks the threads, which opens minute cracks in the rust, allowing the penetrating oil to keep seeping deeper into it. The impact wrench also applies the circular torque without side force. The learning process involves applying some power, but not enough to break the piece. Learning is especially fun when we realize that we have applied too much force, and break it. Then Plan-B comes into play.

jimbeau wrote:

. A variable speed impact wrench is also helpful, because it 'hammers' or shocks the threads, which opens minute cracks in the rust, allowing the penetrating oil to keep seeping deeper into it. The impact wrench also applies the circular torque without side force. .

er,.. we still talking about sparkpluig removal here??

better grab your impact and see if it can get any where near a plug,.

Nick

lol
Now that they finally have these nifty little battery impacts, you can't even SEE the plugs anymore.

jimbeau wrote:

lol
Now that they finally have these nifty little battery impacts, you can't even SEE the plugs anymore.

great little tools the 3/8ths ones,. but doubt if you,d get near #2,#7 or #8 on a LT1,.

Back when grandpa and I were kids I watched a machinest remove broken studs from a large very coroded boiler casting. He placed a nut over each stud which was broken about flush and arc welded the hole of the nut to the stud. He then relativily easily turned the stud out using a wrench. Obviously the nut gave him a place to use a wrench. He also said the heat from the weld caused the stud to expand. Since it couldn't expand laterally it expanded lengthwise thus getting thinner and making it easier to unscrew. If this explanation is correct, will it help to heat the metal on the plugs with a torch before trying to remove them? The spark plug with its seat does make it a bit different than a plain stud. Just something more I was thinking about today.
Eric

I HAVE used mine in some situations with a u-joint coupling; just because it's easier.
They don't have to be as tight as folks think they do. My little DeWalt variable speed
1/2" job is about the same size as a pop can.