That's the thought I'm having while reading this. Having removed stubborn bolts (never had the pleasure with glo plugs on a 606) buy backing out only as much that is wise, then spraying with juice, returning bolt back in, then out again.... repeating procedure. Taking notice to see if I can gain any turns.
Turning the bolt back in, takes the lube with it, so the next set of threads get some.

What living in the rust belt teaches

__________________
1999 E300DT (131,800) 154,000 Black on Black SOLD

2006 CLK 500 coupe Capri Blue on Grey (zoom,zoom)
47,000mi

04 VW TDI Passat 80,000mi
(Techno)

How to eliminate oil dependency through market-driven approaches.
“We could cut oil use in half by 2025, and by 2040, oil use could be zero,”
The Sound of Diesel Speed
Ode to MB

Yes, I'm pretty sure I did.

I did a little destructive testing this afternoon with the old glowplugs. My old plugs were Beru branded OEM plugs that were last changed in 2000.

If I hold the glowplug in my vice supported on the case of the plug (the area between the threads and the heating element) the head of the glowplug will shear off at 85-90NM. If I grabbed the glowplug solely from the heating element the heating element would break off at 19-20NM.

I destroyed three of the old plugs and the results were remarkably consistent.

__________________
98 Dodge-Cummins pickup (123k)
13 GLK250 (135k)
06 E320CDI (323K)
16 C300 (62K)
82 300GD Gelaendewagen (54K)

That's nearly double the aforementioned statement where the limit by Beru was declared to be 45 Nm. Good to know...........

Tim's information is all very interesting and informative. Appreciate your posting that.

Unfortunately although installed at 22nm, they require greater force to remove which is where the problems occur; but, is very valuable to know their failure point.

The Beru plug has a slightly longer length nut to grip as compared to the Bosch plugs. Would be interesting to know the fail point of the Bosch plug too. My OEM Beru's came out fine at ~113K. I replaced them with the Beru's again feeling they might be a tad stronger because of their design.

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

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

>>glowplug will shear off at 85-90NM

Very helpful data - thanks for posting them.

That agrees with my experience of these glow plugs. When I removed them, I steadily increased the torque wrench settings, and while most came out at about 50Nm, 2 of them needed a bit more. I was a bit worried about going beyond Beru's 45Nm figure, but I thought it likely that they were being cautious in their specification.

As I've mentioned a time or two, it's worth plugging the vacuum lines and starting the car with the inlet manifold off. That's how I found the failed inlet valve seats on my engine which otherwise would have remained dormant, but still sapping fuel and performance.

have you looked at these GP's?

http://rb-aa.bosch.com/advastaboschaa/Product.jsp?prod_id=26&ccat_id=20&language=en-GB&publication=1

__________________
raMBow

1999 E300DT Obsydian Black Metallic, Heated Full Leather Parchment options, E2, K2, 136,000+, best 36.5 mpg - GP's 12-04 & 11-12 Zero Stuck
2010 Honda Odyssey - The BrideMobile - best 26.5
(2) 2005 Honday Accord- (1 -Corporate 1 - Personal) - 110,000 4-cyl 30mpg
2000 VW Golf GLS TDI, Upsolute Chip (sold to Brother, now 300+k on it) 48.5 mpg like clock work
1987 Honda CRX HF - Sold 87,000 always over 50 mpg Max 67 mpg

I think I'll let someone else be Bosch's Guinea Pig on the Duatherm GPs. Time to take some pictures of the proceedure.

I believe the key to have them not seize again is to tighten them really well to seat them in the head. I believe the recommended torque is not always enough to to do this. I have had a plug seize in a year from not being seated well.

__________________
-disav

99 E300 TURBODIESEL Astral Silver 282K - AMG brakes, suspension, monoblocks, speedo & interior - Full Load Maxed on IP by custom Speed Tuning USA Chip - T3/T4 Garrett - EGR/MAF delete
98 E300 TURBODIESEL Alexandrite Green on black leather 289K
95 E300 DIESEL Green Queen 267K SOLD
84 300D 216k SOLD
87 300D 299K #22 head - intercooler - full load adj. - 8sec 0-60mph - SOLD
76 300D 214K SOLD

Okay folks,

I've got the Intake Manifold off and I lubed the Glow Plugs. I tried a 10mm socket on the plugs and it didn't fit, Hmmm....

I tested continuity on each plug and all but #2 read about 0.5-0.6 Ohms. Only one bad??

12mm fit the Glow Plug heads just fine and I gave each plug about 18NM with the 3/8" torque wrench. As I twist on #2 it comes loose way before I get to 18NM, Hmmm....

I haven't pulled #2 out yet, I just left it where it was and applied more Liquid Wrench. Will give them a try tomorrow as well.

Okay folks,

It didn't take a full week. Today was day number two and all plugs came loose with no problems. #2 is of different vintage then the other five so that may be an indicator or past activity. All were Beru GPs.

Seems like this slow measured approach may be worth noting. I still plan on taking mine out when I get the time.

__________________
raMBow

1999 E300DT Obsydian Black Metallic, Heated Full Leather Parchment options, E2, K2, 136,000+, best 36.5 mpg - GP's 12-04 & 11-12 Zero Stuck
2010 Honda Odyssey - The BrideMobile - best 26.5
(2) 2005 Honday Accord- (1 -Corporate 1 - Personal) - 110,000 4-cyl 30mpg
2000 VW Golf GLS TDI, Upsolute Chip (sold to Brother, now 300+k on it) 48.5 mpg like clock work
1987 Honda CRX HF - Sold 87,000 always over 50 mpg Max 67 mpg

Congratulations! Looks like you are on your way to a successful change. Remember to use a high temperature rated anti-seize compound on the threads, as a minimum. I have also typically coated the back end of the heating element as well. Good luck, take your time and it will all go back together again. And, next time it won't seem quite so imposing. 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)

Right, now if you could all tell me how I remove my #2 glow plug, which the previous owner welded to the head with a washer, I'd be delighted

Woo Hoo!! All plugs are in and the car starts just fine. Used plug reamer and there was all kinds of carbon build up in there. I didn't even have to have the CEL cancelled. After three days of driving the CEL went out by itself. I guess they (MB engineers) were smarter than I thought!

Now on to the '77 240D and it's steering.

First, shoot the PO, or at least get them into a good digging match and give 'em a good wallop. Second, find a good machine shop. Third, I hope you're wealthy.