Help- Sparkplug broke off in head!
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,131
Likes: 106
From: laingsburg MI
2020 C3 of the Year Finalist - Modified
Help- Sparkplug broke off in head!
Helping a neighbor change plugs in his dodge v-10. Plug broke off at the top of threads to the porcelin area. The porcelin did not break off, but the hex head off the plug broke off, leaving the thread barrel & ground strap in the head, while the porcelin slipped free & is out, with the hex head attached. Strangest thing I have seen.
Currently I have been soaking the thread in PB rust buster & have inserted an ez out in to the threaded barrel. The ez out is grabbing & holding but I am afraid that the torque required to break it free would break the ez out first. I would guestimate that i have placed 60-70 ft. lbs. of torque on my breaker bar trying to loosen, with no luck.
My O2 is empty on my torches, so tomorrow I will fill the tank & place some heat. Any ideas or common experience? thanx
Currently I have been soaking the thread in PB rust buster & have inserted an ez out in to the threaded barrel. The ez out is grabbing & holding but I am afraid that the torque required to break it free would break the ez out first. I would guestimate that i have placed 60-70 ft. lbs. of torque on my breaker bar trying to loosen, with no luck.
My O2 is empty on my torches, so tomorrow I will fill the tank & place some heat. Any ideas or common experience? thanx
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Heat and penetrants are your best bet. Obviously avoiding drilling until you have no other choice. Maybe a few well placed and specific blows with a tack hammer to the head casting surrounding the plug bottom to break any rust or corrosion bonds.
Racer
Joined: Jul 2006
Posts: 499
Likes: 0
From: Colebrook Connecticut
im betting they were bosch plugs.
happened to me
got the sucker out using a pair of needle nose vise grips.
otherwise last resort would be to weld a bolt to it and go from there.
ez out could work if you got the biggest one you can fit in the hole.
happened to me
got the sucker out using a pair of needle nose vise grips.
otherwise last resort would be to weld a bolt to it and go from there.
ez out could work if you got the biggest one you can fit in the hole.
Last edited by rabiddawg; Jun 27, 2007 at 08:21 PM.
3rd Gear
Joined: Jun 2007
Posts: 3
Likes: 0
Help- Sparkplug broke off in head
WOW thats weird! they probably didnt put any no-seiz on the threds when they installed it in the aluminum heads heat may help but unfortunatly the best way is to pull the head and remove the plug as you may have some chunks down in the cylinder. Sucks to be U good luck!
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,131
Likes: 106
From: laingsburg MI
2020 C3 of the Year Finalist - Modified
iron heads. will try heat & more penetrate with ez out tomorrow. will post findings. don't want to remove the head on this v-10 mopar.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Sounds like you have an open hole down inside the cylinder.If this is correct you can trim a hack saw blade to go down through the hole.Take a hammer and remove the pitch from the teeth to make the blade thinner.Make 3 slices through the spark plug just into the threads.With a small chisel and a magnet tap each piece away from head threads.This will leave the 3 small scores in the threads in the head-shouldnt hurt since the taper does the sealing.
Last edited by ...Roger...; Jun 27, 2007 at 11:42 PM.
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Burning Brakes
Joined: Apr 2004
Posts: 847
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From: Des Allemands LA
A little "tool" we use to use in the machine shop was a tap that had been ground to the shape of a square and slightly tapered (4 sharp edges). The size needs to be just big enough that you can't push it all the way through the threads and can tap it in with a hammer (small) to engage the sides of the remaining threads. This will dig into the sides without pushing outward like the EZ out.
ltlevil
ltlevil
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,131
Likes: 106
From: laingsburg MI
2020 C3 of the Year Finalist - Modified
Successfully removed the thread barrel of the spark plug from the head!! Used a medium sized welding tip & applied heat (a fair amount) & was able to turn the thread out with the ez out. When it was removed, it was evident that it twisted & snapped off right below the hex head as thought.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Successfully removed the thread barrel of the spark plug from the head!! Used a medium sized welding tip & applied heat (a fair amount) & was able to turn the thread out with the ez out. When it was removed, it was evident that it twisted & snapped off right below the hex head as thought.
Does it look like it was cross threaded when it was installed?
Instructor
Joined: Aug 2006
Posts: 188
Likes: 1
From: Kamloops BC
Had the same thing happen on my daily driver, a 1986 Mazda pu. I took the poor little truck over to a buddy who restores very old industrial tractors, he welded a bolt into the remaining part of the thread and turned the thread out.
Dale
Dale
Safety Car
Joined: Oct 2000
Posts: 3,547
Likes: 12
From: Carbondale Pa.
Same crap happened to my last Honey's car a '94 Fleetwood Cadillac (LT 1) and almost ruined our upcoming vacation, I had to rent a car , sprayed the hell out of it with penetrant before we left and when we got home sprayed it some more untill I was calm enough to get it out, soaking and being honked off at it, it literally fell out when I used a large by large eezzee out. It was caused by the extended intervals that the later model cars specify for normal maintainence . It was an A.C. plug. I spent most of the vacation thinking about how in the hell I was gonna get the broken plug out. That sucked, but managed to have a decent time anyway,,,,Peace,,,Moosie 
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
Successfully removed the thread barrel of the spark plug from the head!! Used a medium sized welding tip & applied heat (a fair amount) & was able to turn the thread out with the ez out. When it was removed, it was evident that it twisted & snapped off right below the hex head as thought.
ltlevil
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,131
Likes: 106
From: laingsburg MI
2020 C3 of the Year Finalist - Modified
there was no thread damage, as the new plug threaded in as one would expect. I did state that the new plugs had to have anti-seize on them. I think that they were the orignal plugs... left in too long.
