'98 E300 TD with glow plugs stuck in head - Page 5 - PeachParts Mercedes-Benz Forum

Todd Miller · #61 02-23-2009, 11:31 AM

I'm voting, "drive it" also......and yeah, up a hill where you're ramming as much air into as it'll take. And get some Kroil in that hole, fill it, and let it be sitting like that over night. Kroil is amazing.

mikemass1221 · #62 02-23-2009, 11:32 AM

I ran it around for a while. Warmed it up and the gunned it on an uphill entrance ramp to highway. It's ashame cause it runs so great. It's just a miserable start. with the bad GP. Actually I have another one that's bad too. If it was just the one, I'd consider just driving it like this. But eventually, I'm going to have to bite the bullet and get it fixed. Not to mention, the other bad one... No 5 won't budge at all. no way that's coming out without breaking that one too. OH MAN!

JimSmith · #63 02-23-2009, 12:36 PM

I have been ungodly lucky - I have changed all my plugs at least once in the 140,000 miles I have driven my 1998 E300D TurboDiesel. None have stuck. A few have squeaked a bit coming out, but nothing stuck and broke off.

I "drive it like I stole it" before I try this job, believing that getting the combustion chambers good and hot and blowing out the carbon is a good thing to do. In the Fatherland these things still take a drive on the Autobahn now and then to find out where the engine and air friction equal out. Under those conditions the boost is way up there and the engine speed is also pretty good. We don't get to do that regularly, legally anyway. In the old days, the 1960's and early 1970's I lived in Munich, and a Mercedes-Benz with a flaw like this would have been cause for national disgrace. I have a hard time believing a large number of German/European engines are having this broken glow plug issue like we do. I could be wrong, but it would be a topic in their car magazines and would negatively affect sales. And it surely would not have been repeated in the CDI and new BlueTec engines.

So, drive it like you stole it for a while, and then see if that number 5 unit comes out. Others here have tried a low level impact setting on an impact tool to vibrate the plugs loose, with good results. You can rent such a device, an electrical one, pretty cheaply.

Good luck, and remember, the guy who blew his plug remnant out was driving it for a few weeks before it shot out - he had decided it was not coming out and gave the car to his wife to drive....

Jim

mikemass1221 · #64 02-23-2009, 01:38 PM

I remember reading that post about his wife driving it. Gives me a little smile imagining her reaction.

spock505 · #65 02-23-2009, 01:48 PM

Quote:

Originally Posted by Todd Miller

Well, here's how royally screwed I currently am. While drilling out more of the center of the glow plug, the drill suddenly moved inward about 1/2". Right after that, the outer shaft of the glow plug started to spin in the head and just came right out when I removed the drill bit.

However, the center element had actually come loose and had moved forward.......the sudden movement I got in the drill.....and that 1" or so of electrode tip is now down in the head, inside that last bit of oriface that it would normally protrude through.

It's not attracted to a magnet enough for my pencil magnet to drag it out. I duct taped some 1/4" diameter fuel hose into my shop vac, but couldn't suck it out. Did a test of putting a drop of super glue on back end of a 4" long drill bit and tried to glue that to the electrode of another glow plug....it wouldn't stick.

Anyone have some advice? I thought about cranking the engine over and maybe compression would force it out. But I'm worried that it might fall into the engine. I've pushed gently on it, and it appears to have bottomed out on whatever there is of the pre-combustion chamber. I also thought about removing the injector and using compressed air to blast it out. But the injectors are about 8" long (or look that way) and so it looks like that'll take a special deep socket.

This is so f

cked.

Here's a shot of how far off I got with the drill. I should have been inside the center of that bullseye, instead, you can see how I was off at about 1 o'clock. @#$%!!!!

I did the exact same thing on my OM605.

First I cut the electrode off flat with a Dremel

Then I went at it with a very small drill again using the Dremel gradually moving up a size as I went.

I found it difficult to keep the correct angle due to the electrode sending the drill off at an angle, the next thing I knew about this was a puff of smoke from the inlet manifold as i went though with the drill

I ended up sending it to a head specialist who use the other glow plug holes to get the correct angle then use a jig to plug in a new piece of ally block.

Todd Miller · #66 02-23-2009, 04:47 PM

Man do I feel your pain on that one.

Here are a couple of things that I would do different:
1) First, understand that not only do the GP's angle down, but they all angle forward. All of them.

2) I didn't leave any of that electrode sticking out the top. I cut it off flush, so that I could get a pilot hole started. Then I enlarged the pilot hole until the electrode broke apart, leaving the outer body of the glow plug.

3) Where I screwed up (on #4, the second one I extracted) was that I got over confident in drilling out the GP body. I should have drilled in smaller increments of time, blown out the chips and then checked to see that I still had that nice "bulls eye" showing. This, and the understanding that the GP's angle forward, would have saved me, and #4 would have been out in less than an hour.

4) Not drilling out the outer body of the GP down too deep in the head. I had to do this because of my screw up. Going too deep into the GP body is what caused the center electrode to finally just push right out and into the pre-combustion chamber. The other bad thing about getting too far down into the GP body is that you risk drilling into the shoulder in the head, which is what the GP body crushes against in order to keep carbon and compression from getting up the GP body.

As to the question of, "Is this really a problem here in the states," I'd say yes. This thread along got something like 600 views in the first 2 days. Not to mention the fact that Mercedes as recognized it being significant enough that they engineered an extraction tool kit, to the tune of $1,300! That tells me there were a lot of really mad owners complaining that a $400 job was going to cost them 2k-3k. Just my 2 cents worth.

JimSmith · #67 02-24-2009, 09:35 AM

I did an internet search for this in German to find a German equivalent to MBShop, then posted a question on this subject to find out if it was a USA only problem. It isn't. They have a similar procedure:

http://www.motor-talk.de/forum/guehkerzenwechsel-beim-e-300-td-t1642765.html

One of the guys specifically recommended using a copper based high temperature anti-seize or equivalent compound, applied to the shaft of the glowplug. They also recommend soaking in penetrant fluid, and then driving it to get the engine good and warm before trying to remove the plugs.

Jim

JimmyL · #68 02-24-2009, 09:43 AM

Quote:

Originally Posted by JimSmith

I did an internet search for this in German to find a German equivalent to MBShop, then posted a question on this subject to find out if it was a USA only problem. It isn't. They have a similar procedure:

http://www.motor-talk.de/forum/guehkerzenwechsel-beim-e-300-td-t1642765.html

One of the guys specifically recommended using a copper based high temperature anti-seize or equivalent compound, applied to the shaft of the glowplug. They also recommend soaking in penetrant fluid, and then driving it to get the engine good and warm before trying to remove the plugs.

Jim

Wow, Babelfish had a hard time with that web page, but the pics were interesting......
Good thing Mercedes doesn't have a glow plug issue on these!!

JimSmith · #69 02-24-2009, 10:14 AM

Well, I wanted to know if this was a universal problem and the guys on that site made it clear that it is. I can translate his procedure if you like, but the biggest difference is he turned a nut down on the electrode and pulled it out of the plug before he started the drilling operations.

I will ask them what they think of driving around and letting the engine heat and compression blow the remnant out.

Jim

milner351 · #70 02-24-2009, 12:20 PM

if the electrode could be removed from the center of the glow plug before starting the drilling procedure - that would make a huge difference - however, that also opens up the drilling to the precombustion chamber - and you run the risk of metal shavings getting down on top of the piston.... .that would not be good at all.

spock505 · #71 02-24-2009, 02:06 PM

Quote:

Originally Posted by milner351

if the electrode could be removed from the center of the glow plug before starting the drilling procedure - that would make a huge difference - however, that also opens up the drilling to the precombustion chamber - and you run the risk of metal shavings getting down on top of the piston.... .that would not be good at all.

Agreed, it would perhaps you could even go straight in with a tap after the collar thread had been removed.

Nope, deffo not a localised problem - this is the UK site http://www.mbclub.co.uk/forums/search.php?searchid=2004689

back to the problem and possible remedies, the most successful method seems to be prolonged immersion to penetrating fluid over maybe several weeks - my thoughts were along the lines of assisting this process by putting the fluid under pressure pushing it through the threads rather than relying on gravity/capillary action.

perhaps some sort of seal around the plug (obviously not connected) filled with fluid under pressure, foot pump and valve?

waddyathink

milner351 · #72 02-24-2009, 03:18 PM

penetrating fluid over several nights for over a week did not much to help mine - I think if you can get the GP to loosen even a bit - the penetrant will have a much better effect than if you get no movement at all.

I think heating first, then spraying penetrant on maybe a good solution - as the heat of expansion should help the penetrant creep into the threads and down the barrel.

My stuck plug is much more tenacious than most - no matter what I did it wouldn't come out - I'm glad to hear others have had better luck getting thiers out...

Todd Miller · #73 02-24-2009, 05:05 PM

It's too bad these heads weren't design with a steel sleeve that the GP threaded into. Then for extraction, you simply unscrewed the steel sleave. The GP would be inside the sleeve. If the GP didn't want to come out of the sleeve, no problem, throw them both away.

Boggles the mind how they figured this design was going to fly, and more so, how it passed rigorous testing.

That, and intake runners over the top of the GP's, making a 30min job a several day job.....if you're lucky.

JimSmith · #74 02-24-2009, 08:17 PM

I asked the German guys if this glowplug problem exists on the CDI and Bluetec E300D TurboDiesels, and the answer was affirmative. They seem to feel using the copper based ant-seize is the ticket though and suggested it is the universal fix on the newer cars. Slather it on the barrel of the plug before you screw it into the prechamber and apparently it prevents the baked on soot from actually adhering to the metal surface of the plug barrel.

Jim

JimmyL · #75 02-24-2009, 08:48 PM

I'm actually not familiar at all with the prechamber in these, and where the glow plug is relative to the injector. But if the injector is removed I'm guessing that does not allow a different method of getting penetrate onto the body of the glow plug????