Another 606 glow plug removal thread

[ROLLGUY]

My friend had a small coolant leak in his '99 E300, and we determined it was a bad head gasket. He had already purchased new glow plugs, and I was ready to install them when the coolant leak started. I pulled the head, and was able to get five of the plugs out effortlessly. Number three was not so easy. I managed to get it out a little more than half way (soaking it overnight with PB Blaster with the head on it's side, glow plug down) before stripping the hex of the plug. I then took it to a friend to have a nut TIG welded on and heat put to the head around the plug, only to have it break off just below the welded nut. I prepared myself to drill it out by searching here and looking at videos. I was not able to find a good way to drill out the center electrode, so I used a center punch to smash it down inside the body of the plug to make a pilot for a drill. Here is a photo. I can only upload one photo, so I will give the play-by-play with each photo.

[ROLLGUY]

I then drilled out the center electrode wit a bit the size of the inside of the plug:

[ROLLGUY]

Next I drilled out the upper portion as close to the threads as possible. Just for fun, I used the punch to drive the plug into the head to separate the threaded portion, it worked! Now all I needed to do is get the threaded portion out.

[ROLLGUY]

Next I used a screw extractor to remove the threaded piece. For the most part, it came right out.

[spock505]

Hey bud, if you skip forward on this video he gives a good overview of how to remove the threaded portion.

Good luck, been there where you are..

https://www.youtube.com/watch?v=U9AO_cDdwS8

[ROLLGUY]

Here is the piece I got out:

[ROLLGUY]

A view of the hole needing the threads chased. I am headed out to buy a tap in a few minutes.

[ROLLGUY]

After chasing the threads, I am going to screw in the threaded portion of a cut off glow plug to use as a drill guide for drilling for the 5/16 tap. This tip I learned from somewhere on the 'net, and am thankful to whoever posted it. I will let y'all know how it goes when I get back with the tap......Rich

[ROLLGUY]

I got the 12mm X 125 tap and tapped the hole (actually just chased the threads). I screwed in my drill guide and drilled the hole for the 5/16 tap and blew out the chips. I tapped the hole. After blowing out the chips again, I screwed in a cobbled together fixture for my slide hammer, and pulled out the offending glow plug. Hooray!

[ROLLGUY]

Originally Posted by spock505

Hey bud, if you skip forward on this video he gives a good overview of how to remove the threaded portion.

Good luck, been there where you are..

https://www.youtube.com/watch?v=U9AO_cDdwS8

I have seen that video before, and was looking all over youtube this morning for it. Thanks.

[KrustyKustom]

I too have a OM606, mine is a 95 model. Out of curiosity do could you tell where the headgasket was leaking? was it leaking coolant to the exterior of the engine?

Mine has developed a weep at the rear and leaks to the exterior, I suspect that rear O ring on the exhaust side of the engine.

[ROLLGUY]

Originally Posted by KrustyKustom

I too have a OM606, mine is a 95 model. Out of curiosity do could you tell where the headgasket was leaking? was it leaking coolant to the exterior of the engine?

Mine has developed a weep at the rear and leaks to the exterior, I suspect that rear O ring on the exhaust side of the engine.

Yes, that is exactly where it was leaking. In fact, years ago I ha a '95 and it leaked there as well. This car had the head off years ago, but I have not had a look at the service records yet to see what was done. I suspect that only the head gasket as changed, and the head was not surfaced.

[jay_bob]

The right way to do it

As opposed to: OM 606 Drilled too deep trying to extract a stuck Glow Plug