Ought to be only carbon on the GP body holing it now.

Suspect it just needs to be rotated back and forth numerous times and will then free up.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

I'd suggest using a slide hammer to pull it out, but I'm pretty sure you can't get a straight shot at the plug w/o removing the oil filter assembly. I've done that job before and it wasn't fun. My next suggestion would be to clamp extra large vice grips onto the head and use a lever to pry it out. Be extra careful to pry it straight out without any bending forces.

How many times have you tried to rotate is back and forth? Tapping it back in (a little) and then twisting it back out might grind up the carbon sufficiently.

After letting it sit all night with a heavy spraying of PB Blaster, I attached vice grip pliers and twisted and pulled and it came free. You can see from the pic that only about 1/4 inch was all it would come out and the slurry of carbon gunk on it when it finally came out.

Just for reference--the elephant pipe or the corrugated pipe screw (the one you access from underneath) is a Torx-T30.. The manifold screws are Torx-T40.

My glowplug light went out, but the check engine is still on after replacing all 6. Hopefully a trip to Autozone to clear the code will fix this.

Great post--saved a ton of money. Took me a long time, but next time should be easier as my learning curve went way up.

Thanks a million.

Attached Thumbnails

   

__________________
1999 E300 TD
1999 E300 TD, WVO conversion
2007 Jaguar XJ8
1993 190E 2.3, Limited Edition, 239,000 miles (sold)
1991 300 SL (sold)
1977 MGB
1969 TR6
1980 TR8
joturbe@comcast.net

OK, here's a question for the guys who have had to exctract a snapped GP. I have one plug that's snapped off by a previous owner/mechanic somewhere about 1/2" below the hex portion. In the hole, I can see a solid black obstruction. When I scratch it with an awl, it feels like a solid bolt or some hard metal.

Is this what a snapped off GP looks/feels like? It's in the No.6 position so I have pulling the oil filter assy. to look forward to...

Thanks.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

I recall the center electrode being silvery in color. Of course it could have oxidized. But it wasn't a very hard metal. My guess is that you are looking at the end of a broken off EzOut.

You could try using normal drill bits to drill out the obstruction. Just make sure the bit stays centered. If that fails, the head will likely need to come off.

Great job! Congrats. No reset is necessary, the CEL will reset itself after a number of normal glow/start cycles...I think 5-6 of them will do it. Unless you have tripped some other code, that is...but assuming your CEL is from the GPs then it will reset and clear automatically over time.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

If I have not aready said this; I hope you plan to ream out the carbon from the Glow Plug holes.
I mention this again mainly for the newer members who have not had to face your problem yet. Seeing is believeing; your picture helps.

__________________
84 300D, 82 Volvo 244Gl Diesel

I just removed my air intake. I can see that indeed there is 180K miles of residue in the intake tubes; I can clean that out out. But what about down in the head itself. Is there anyway to clean that out? On some of the intake ports the build up is greasy and on others it's more of a dry cake. 1996 E300D. Thanks! Excellent instructions

Guys, glad to see people are still using this guide, you're all very welcome. Wish I got on mbshop more often, just haven't in quite some time due to selling my E300.

Humzinger - with that many miles I'd consider pulling the head and cleaning it too, depending on the amount of gunk. Mine had minimal buildup in the intake ports, although I did stick some random tools wrapped with biodiesel soaked rags down mine to wipe out what I could.

__________________
2004 Ram 2500 Cummins HO
2000 Jetta TDI
1999 E300 (sold)

Fantastic report. The fear is gone! Well almost.
Thanks

__________________
1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

I'm trying to envision this process. how is that the reamer won't break up the carbon, and then that carbon gets pushed into the cylinder when you push the new glow plug in?

After reaming the hole, you're supposed to crank the engine over for a few seconds to blow the debris out. A little carbon won't hurt anything if ingested into the combustion chamber, but you don't really want any carbon around the new glow plugs...

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

I need to do this job also ...w/ 176K miles on the clock and the glow plug light staying on......

I'm wondering if burning some B100 might have dissolved some of this carbon buildup ??

Back when diesel ran up so high....at one time almost $5.00/gal in CA......I had a good source and .... . bought a couple of 55 gal drums of it and burned it....sometimes straight....sometimes 50/50......until it was gone. Haven't used any bioD in about a year though.

Guess I'll find out when I pull the manifold......been dreading the job and putting it off for several months. Maybe I should burn a couple of tanks before doing the job.

Warren C.

Guessing that when the plug gets weak and then stops glowing is when "most" of the carbon collects. When working, they get red hot; something like 1200F.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Actually they shut off when the car is running after a short period of "afterglow" which sounds almost pornographic. The driving style, and I suspect, the EGR flow, lead to conditions of higher soot formation inside the engine. We don't notice this as an external soot discharge from the engine because of that soot oxydizing catalyst drum in the exhaust. But lots of loafing around will pack carbon inside the crevices in the prechamber. And, once the carbon is there it is a good thermal conductor - much better than air - and it draws the heat from the plug into the prechamber. The larger mass of the prechamber and cylinder head will prevent the plug itself from burning away any soot deposits completely, and may contribute to hardening it in place.

Find a long hill and after all is at normal operating temperatures take a run with the throttle pretty much wide open up the hill. Take a few passes. The idea is to get the temperatures up and flow rates up so you can burn off some of that stuff before you attempt to pull your glow plugs.

I have been relatively fortunate - I have not had any plugs stick and, changing them only as they fail, I have changed all 6 twice now. One was actually no more than hand tight the first time I tried (number 6), leaving me to suspect the dealer did that one in the past without taking the manifold off. And I have taken to using the car wash bays for DIY with the high pressure nozzles as the place to clean my manifold out. Does a great job on about 85% or more of the inside in about 3 to 5 minutes. Takes longer to clean out the bay.

Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)