ChuckD

The Porsche continues to test me. Even a simple plug change while the intake is off has gone south. I've never seen this before. As soon as I turned my ratchet, it let go. The threaded part of the plug remains in the head. The rest is out, as you can see. I'm going to try an easy out that will fit the diameter of the hole and see if it will bite enough to get it out.

Has anyone ever seen this before? If so, what was the best way to remove it?

MainePorsche

Bump for Chuck.
Other than tooling it through the hole as Chuck plans with perhaps a little PB solvent soak, I am curious to see what the community adds.

joejoe

Never seen one do that before. Pull threads, yes, but not break off.

OTR18WHEELER

whats that grey colored stuff?, Did PO JB weld the plug in a stripped hole?

FiveElements

This happened in my friends Boxster 996. better soak it with anti-lock solvent first. With broken bolts that still stick out high enough, I dremel tool a cut and use a large screw driver cut to turn the bolt. But don't think you can reach into that hole to cut.

Mrmerlin

Great thread title BTW,


put the piston at TDC,
Add some PB blaster get the best easy out you can find ,
IE snap on comes to mind then insert it to the plug and unscrew it.

If that wont work put a ball bearing into the hole thats bigger than the opening of the plug get a welder
and weld a larger with say a 12 MM opening nut to the top of the plug then unscrew the nut ,
the ball will prevent any junk from falling into the cylinder

Fogey1

Great pic, btw. If the gray stuff is JB Weld you'll feel the diff with a sharp probe but I'm not sure this would change the advice.

If it were me ...

First close the hole into the cylinder. Chop stick, eraser, maybe even a dab of silicone caulk.

Second, fill the well with penetrating oil and let it sit. 50/50 ATF/Acetone.

Third, get an easy out to fit that 1/8" rim that's left from the separation _or_ one that will fit the small hole. (Before I did that I'd want to figure out the plug construction for sure.)

Basically your main priority along with getting the plug out is not letting any hard stuff fall into the cylinder.

G8RB8

That electrode looks terrible. First thing I would do is pull another plug or two and have a look with a bore scope to be sure you don't have a situation like this..
https://rennlist.com/forums/928-foru...ot-pretty.html
If so you'll be pulling the head anyway.

FredR

For a plug to let go like that I would think there must be something seriously wrong for this to happen. As other have intimated maybe a PO stripped the theads and did a "get rid of" job on it?

Worst case scenario the head has to come off so nothing to be lost by trying no matter what and you can always vac out the cylinder and/or insert an endoscope to see if anything left in there.

Keep us posted how you get on & good luck.

Fred

Landseer

Search net, there are tools for this, one might work in the deep recess

linderpat

this is actually a common problem on the 3 valve 4.6L mustang engines - this winter, I had 4 out of 8 plugs break off. The Ford problem is due to the use of a two peice plug, and the carbon build up on the shaft. No matter how careful you are, they break. Sickening feeling.
There is a tool - called a Lisle tool (about $90 on Amazon) that I used to remove the broken part from the chamber. A bit tricky at first, but not a bad process. Not sure if it will work in this situation.
Anyway, here is a video:

ChuckD

On my mobile device, but wanted to reply. First...thanks! I expected this to be rare. There is no JB weld. It's just cleaner aluminum down in there. I am at TDC and looking to keep stuff out of the cylinder. Other plugs looked black, but only center electrode. This seems to be a two piece plug, as was mentioned, to even have this happen. All plugs on this bank came out slightly easier than other bank and they seemed to have some type of clear antisieze. They had a "wet" look to them and were slicker. Strange. Anyway, going to think about my approach. Using an extractor would likely drop shavings into cylinder, which I could maybe vacuum out with a small tube at the end of my shop vac. I appreciate the responses and will definitely keep you posted.

Kevin in Atlanta

Ball bearing to prevent shavings from entering the cylinder and a short extractor would be my choice. My experience has suggested that the larger the extractor the easier the extraction works. So, I'd find an extractor that grabs closest to the top of what you have left in the spark plug hole.

ChuckD

Now that I am looking at the photo closer, I do see the the gray color that is not the same as aluminum. It was late last night and dark and now I have to investigate that more. Wonderful.

Chalkboss

Outside of the methods described here I don't have a better alternative but I feel your pain. I had a FJ40 that crapped on my soul with stripped/overtightened/broken nuts and bolts. No job was easy, but selling it was. Good luck to you and let us know how you get it out.