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Rounded sparkplug

I started changing the sparkplugs. on the last plug I noticed the socket was a little loose. Itried pulling easy on it and the socket slipped. then I found a socket 1/64 inch smaller put some PB Blaster on the plug and tried to turn it same thing. now Im left with a dead sparkplug that is rounded off. does anyone know of a tool i can use to get the plug out? or any other sugestions?

Helps to know what car and what engine. Put pliers or vice grips on it if possible and turn carefully. Sometimes taking the next smaller sized deep socket will work.

I cannot begin to imagine how you can have a rounded off spark plug. A rounded off bolt which has been removed and reinstalled on a REALLY old car is one thing. Can you see this rounded off? What size is this socket you’re using? Have you taken one of the other old plugs and found a perfect fit six point SPARKPLUG socket? Try this. If it’s truly rounded off, you could have to removed the head to fix it.

The plug is rounded off for sure. The car is a 93 Ford Festiva 4 cylinder. I cant get any type of pliers on it because there,s no room. I’m trying to keep from pulling the head if I can help it. Any other suggestions?

sears sells bolt removers. i am not sure they have one large enough for the hex of the plug. you would probably have to break off the ceramic part to be able to get it on though.

take one of the old spark plugs and break off the ceramic part. see if it is possible (or desirable to do this) if no pieces break off, where you won’t get broken pieces in the cylinder then that may be a possibility. take an old plug to sears and try it. (open the box) make sure it fits down over the hub of the plug. the only drawback may be if the socket needed is too large for the depression on the head.

this set goes up to 3/4" and has a hollow center so it should go over the whole plug. you can use a larger socket to turn it…

actually i may go buy one of these just because. it looks like it could come in handy one day.

What size socket and what brand socket were you using? I think this vehicle uses a 13/16 socket and if a cheap off-brand socket was used it’s possible to round the sharp corners off a little bit anyway.

There can be a lot of variation in the nominal size of some less expensive sockets and you might consider using a deep well impact socket. The wall thickness on these can make a noticeable difference and I don’t see how a plug could be rounded off so badly that it will refuse to come out.

I drove a smaller socket onto the sparkplug then tried to turn it while tapping on it with a hammer ,but it slipped the socket before it turned. Thats how it got rounded. I think the plug is seized up. Ill try what you have said thanks for your help. Any other sugestions?

Again I would get an actual spark plug socket (6 sided) from Sears, and give that a try. For 99% of cars, there is only 2 sizes of spark plug sockets. A spark plug is very thick at its hex head. I can’t imagine there isn’t SOMETHING to grab. It would seem you’ve probably been using the wrong size, and maybe a good quality socket as ‘ok4450’ mentions might do the trick.

Good luck

are you using a 6 point socket or a 12 point deep socket?

stop using a 12 pt. only use 6 pt

I started with a 6 point. The previous owner might not have. the plug was already srtipped a little.

Something isn’t right here. I can’t see a spark plug being put in with enough torque to round the corners off. I wouldn’t think the head would hold it without stripping the threads in the head itself.

Can you get to a corner of it with an air hammer? If you can, you could hit it a few licks with the air hammer and see if that budges it.