Help! - Spark Plug Broke off

[TFastle]

While working on my VolvoPenta 3.0 I decided to do the plugs and plug wires. First plug came out fine but the second one snapped off with fairly minimal force. Upon inspection the metal below the "bolt head" portion was very corroded and just twisted off. I managed to remove the core and porcelain (very carefully) so am left with what is basically the metal portion threaded in with a 9/32 hole in the middle with the electrode on the bottom. Any good ideas on how to removed? My plan at the moment is to keep hitting it with penetrating oil and try an "easy out." Anyone have a better suggestion or any ideas on how to make that option most likely to work?

Thanks very much!

Man ... these boats can have some issues.

 

[Bt Doctur]

Re: Help! - Spark Plug Broke off

Forget the easy out , especially if you break it.
Try running a tap into whats left clean with acetone, install a threaded bolt with Red Loctite
Then apply the heat and penetrating.Other than that, removal of the head .

 

[achris]

Re: Help! - Spark Plug Broke off

.... Upon inspection the metal below the "bolt head" portion was very corroded and just twisted off.

Begs the question of how long were those plugs in there??

Man ... these boats can have some issues.

Lack of maintenance will do that.....

 

[Silvertip]

Re: Help! - Spark Plug Broke off

Had that happen to a buddy who owned a 1992 Olds Bravada with the GM 4.3 V6. It only had 70,000 miles on it but the plugs were in the engine for 16 years. He was leaving our cabin and had to climb a very steep hill towing a fully loaded boat and half way up the engine lost power and began missing. I went back to find them when they didn't appear on the downside of the hill. Turns out the crimp on the plug let go and pushed the insulator out so he had a "huffing" cylinder. Attempts to remove the shell of the plug resulted in the exact same scenario -- the shell broke off. The local dealer did the extraction using the procedure suggested above. In the process of changing the other plugs they broke off two more. The lesson here is to change plugs frequently whether they need it or not.

 

[TFastle]

Re: Help! - Spark Plug Broke off

Acris, begs the question ... why'd you leave idiot out? Thanks for the input.

 

[achris]

Re: Help! - Spark Plug Broke off

Achris, begs the question ... why'd you leave idiot out? ....

Well, if the cap fits..... You said it, not me....

 

[TFastle]

Re: Help! - Spark Plug Broke off

Well, if the cap fits..... You said it, not me....

It was SARCASM -"harsh or bitter derision or irony". The point being you don't know anything about me or the situation and this forum isn't for those with high opinions of themselves to insult others. If you have something of value to offer then do, if not move on. Get the point or does that need to be explained as well?

 

[mikecjn]

Re: Help! - Spark Plug Broke off

Just went thru this recently on my Dodge Ram...it is not impossible to fix.
The hex head and the rest of the plug came out leaving the threads still in the motor head.

The way I got it out took a couple days. If you have the patience and the time go for it.
I got a small piece of pipe that was about the same size as what was left in the cylinder and a ball peen hammer. I sprayed the heck out of the plug with Liquid Wrench and let it sit over night. The next morning I went out with the pipe and hammer, set it on the plug threads and gave it a dozen or so taps with the hammer. Not too hard but just enough to vibrate it a bit and start to break some of the rust/corrosion that may be on the threads. After I did that I sprayed the heck out of it again and let it sit again till that evening when I did it again.
I did this for two days and then used a spiral ez-out on a ratchet. After another set of tapping with the pipe I tried the ez-out and she popped free and backed right out.

Be very careful to stay a straight 90 degrees with the tap or you take a big chance of breaking it. Take it slow also...if it seems like it isn't quite ready to come free give it another day if you can.

Last thing, when you do get it out, use a shop vac afterwards and try to get all rust flakes etc out of the cylinder before you put the new plug in and coat the new plugs with antisieze.

Good Luck!

 

[KJSmitty]

Re: Help! - Spark Plug Broke off

"This forum isn't for those with high opinions of themselves to insult others."

Well,,,,

To quote a line from a movie:

"Sir, that information is not entirely correct."

Many strong opinions here.


Some good suggestions above. The one thing I would add is to ensure you have that cylinder/piston at "bottom dead center" to ensure you don't inadvertently strike the top of the piston with a removal tool/device etc.

- Best of luck with your issue!

Cheers and welcome

 

[T-Max]

Re: Help! - Spark Plug Broke off

...Last thing, when you do get it out, use a shop vac afterwards and try to get all rust flakes etc out of the cylinder before you put the new plug in...

Ditto that. And if it were me, I'd not put a new plug in before starting the engine without a plug in that cylinder so that it might blow any "chunks" of stuff out the spark plug hole.

In fact, it might be a good idea to first blow some compressed air into the cylinder and see if you can hear anything rattling around inside. Even blowing with a larger-sized straw might serve that purpose. You don't want any larger "particles" in there or they could end up burning or blowing a hole in your piston. I note that you said you've removed "the core and porcelain" so it's possible some of that might have fallen down inside .....

Blow air in there and keep looking inside with a good strong flashlight and see if anything shows up into your field of view.

Taking the head off is the safest and bestest way of dealing with this problem, but that's a lot of work for sure.

Might not be a bad idea, though. I just pulled my head and was a bit surprised to find what I found. It's simple enought to do a simple head reinstall, so ......

Good luck and let us know how you made out.

 

[TFastle]

Re: Help! - Spark Plug Broke off

All very good suggestions. I have it soaked in penetrating solution right now and will continue this for a day or two and give the easy out a try. I kept all of the porcelain pieces and it all is accounted for but certainly there could be some small flakes. I sucked it good with a shop vac and plan to do that again as well with a straw like tool I have. If I am lucky and get the plug out I plan to turn it over with the plug out a bit first.

Again, great input and suggestions. Thanks very much! I will post here how it works out.

Thanks again!

Tim

 

[Fishing56]

Re: Help! - Spark Plug Broke off

This happened to me on my old hunting motorhome. It has a dodge 440 engine in it and the plug rusted just as yours did. Luckily I had good access to the hole. I carefully drilled out a good portion of the center of the plug and then used a spiral easy out alone with heat to carefully remove the shell of the plug. Just need to be careful will drill bit selection and angle.

Fishing56

 

[Rocky_Road]

Re: Help! - Spark Plug Broke off

I once read an article in a machinist's magazine where they field tested various products for freeing up frozen parts. I saved their results:

Penetrating oil ..... Average load*
None ............ ......... 516 pounds
WD-40 ............ ...... 238 pounds
PB Blaster ............ . 214 pounds
Liquid Wrench ..... 127 pounds
Kano Kroil ............ 106 pounds
ATF-Acetone mix....53 pounds

*The ATF-Acetone mix was a "home brew" mix of
50 - 50 automatic transmission fluid and acetone.*

If this were mine, I would try the 50/50 ATF and acetone brew....

Good luck!

 

[JustJason]

Re: Help! - Spark Plug Broke off

Interesting... was that an online article Rocky Road... and do you happen to have a link to it?
What do they mean by "average load"?

 

[KJSmitty]

Re: Help! - Spark Plug Broke off

Interesting... was that an online article Rocky Road... and do you happen to have a link to it?
What do they mean by "average load"?

Just google - tons of references to the same...

"Average load" - that was a phrase I used quite often when describing my sons diapers many years ago.... However, that may not be relevant here....

 

[Alpheus]

Re: Help! - Spark Plug Broke off

I swear by the acetone/tranny fluid mix. I have been using it for a couple of years now and its a miracle worker. I was told by an old timer diesel/tank mechanic and I thought he was nuts, but it really works...

 

[CVX20SPRINT]

Re: Help! - Spark Plug Broke off

You can buy stubby easy-outs that work better than the normal ones.They're not even long enough to touch the electrode that's still attached to the threads.They have a 1/2 inch hex head so you can easily use a socket and ratchet.I've removed lots of broken plugs with these when I worked at a GM Dealer(15 years)and never even had to soak them.The spiral on the easy-out is a better design/angle and will usually grab the plug shell without even tapping it in.Just put it in your socket,turn while applying slight inward pressure and they will usually come out pretty easy.Most of the time what's left of the plug is not rusted to the head(unless there is water in the cylinder),it's just that the exposed part just rots off.Just my own experience.

 

[dccordell]

Re: Help! - Spark Plug Broke off

I just went through this exact problem with my 470. Two of the plugs had rusted to the point that there was nothing left for a plug socket to grip. I pulled the porcelain out with pliers. Then I soaked those suckers with some spray Kroil. That stuff works pretty darn good on anything! I used a thin piece of scrap metal and a hammer to tap on the remaining part to help free the rust (but don't tap on the threads!). Then I used an easy-out from AutoZone (yea yea.. it's local and a 4pc set was $10).
As was mentioned earlier, it's **extremely** important to keep the easy-out straight in the plug hole. I used a socket wrench to turn it, making sure to not pull more to one side causing the easy out to lean over and break. It did take quite a bit of force on both of them, but they eventually came loose. Once it broke loose, it came right on out.

Take a look at those plug threads after you get them out. Mine looked as good as the others but I ran a tap through them just to make sure.

Funny thing is that the hardest part of this job was getting the remaining part of the plug off of the easy-out after I got it off the motor. A table vise would have made that a lot easier!

Good luck...

 

[artificialreef]

Re: Help! - Spark Plug Broke off

And once you get it out use anti seize so it doesnt happen again.

 

[glennwolf]

Re: Help! - Spark Plug Broke off

Just removed 2 out of my 3.0L two weeks ago. Use large easy out that I cut off about half way so it would not hit the electrode tip. Came right out. Vacuumed out through sparkplug hole and then turned engine over with no plugs installed to blow anything else out. Good luck!