Holy cow, $1400 or $650/GP, sheesh. When I did my 606 GPs only one was really stuck in(carbon). I used a torque wrench set below the shear torque noted by others for the 606 GPs. 1/4-1/2 turns back and forth, with liberal PB(dont have kroil) shots and about 20-30 minutes soak time. Took a couple of hours to get it loose and quite a few nerve racking carbon squeaks. The others came like butter using a HF impact driver, which may have helped. If you have a block heater use that while working on it, keeps things warmer.

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Treetops
06 E320 CDI 127K Miles
87 300TD 231K Miles

99 E300 269K Miles-Sold

This is the only MB dealer in town and they know it. Couple indies but I don't know them enough to trust them.

I'm on the road next 3 weeks straight. Can't afford any surprises and have no time to do the job especially based on the chances something might fail. If it was as easy as om603 I would already have it done.

My wife needs her car and I can't take the risk I would break something.

They quoted me a firm price for the job, if they bust one off in the head that is on them as far as I'm concerned.

Maybe not the best way to spend $1400 but I need the peace of mind of knowing it's taken care of and I don't have to worry about something going wrong and her car being down and I have to get on the plane again.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Really just make sure she gets a loner while they are doing the work then who cares how long it takes them.

They are giving her a loaner car. Part of their standard service. Plus this qualifies for an 18 month renewal in MB Roadside Assistance. That is an added bonus with me being gone so much.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

I have done many glow plugs in om642's and knock on wood none have broken yet. Also, i would add that i would not replace the relay unless its throwing a fault code, generally dont see them go bad yet so this would save you a bit of cash, but thats up to you.

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1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg

please keep us up to date on how this job goes at the dealer
how many miles on your ml?

a while back i did some searches on this and did not come up with much, will be interested to see if they break one or have any trouble

just a side note, had a glow plug stick on my om648 and wanted to soak it in the kroil oil
that stuff is hard to find anywhere in town and takes a while to get here once ordered

so for anyone thinking they may need some for a job in the future go ahead an order it now or you will be waiting a week to get it
it is a good penetrating oil, supposed to be much better than pb blaster etc that you can get at auto part stores

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Courtney
2006 E320 CDI
2008 ML320 CDI

I had mine out for preventative maintenance, it was super easy and simple job. Yes there are things in the way to remove, but straight forward job. They are somewhat tight and never have any antiseize on them. What causes them to break off is carbon creeping up the bore and holding the section below the threads from turning, hence taking them out once in a while to clean them is good sense.
There are tools available to remove them, low speed air impact wrenches just for glow plug removal jobs (very light on torque but lots of hammering), soaking the bores is unlikely to help much-it would have to travel way down the bore past threads and soften the carbon. Mine were mostly clean upon removal. I reamed and blew out the bores, applied anti seize to the contact areas and installed. There are nice bore brushes out there for getting the bores clean or reamers.
Glow plugs are $30 on rock auto for OEM NGK, I would say 1.5 hours is a good repair time for the job max 2 hours, $1400 is a long way from that!

For that kind of money, I'd tackle R&Ring them myself.

Did you happen to chronicle the job with sequential pics, or YouTube vids? Was the head heated up in any way before or as you attempted to remove each GP?

It's done.

Vehicle has 126k miles.

Replacing them myself was not an option with my work load and travel schedule as I mentioned previously.

I hated spending that much money but I could not afford trying to take this on in my ~48 hour window I was going to be home.

Also I would have had to acquire the proper tools and the parts in time to start this morning.

I got back the bad plugs, #5 looked terrible from not having fired in a week. It's true, they do depend on the GPs for normal operation for the stupid DPF regen.

OE plugs on the sponsor site $77/ea x 6 = $462.
OE relay $199
Reamer $79
That is $740. Figure another $30 for shipping so $770.
Plus I have to declare that $770 on my state income tax and pay 8% or another $62.
We're up to $832 and I haven't even started the job yet.

It was definitely worth the $600 to have someone who knows what they are doing take care of it, and have all the special tools at hand if something went wrong.

Plus my wife was able to take the car to the dealer herself, drive away with a loaner, and pick it up when it was done. I come home to a happy wife and don't have to miss what I had plans to do this weekend to work on the car.


Ok off my soap box.

The repair invoice had an interesting comment. The comment from the tech is that it is mandatory to replace all the plugs and the relay if any plug fails.

I believe in symmetrical maintenance so I would have replaced all the plugs on principle anyway but I would like to know if the statement is true. If there is someone on the board who is a current, certified MB mechanic, or service advisor, I would like your opinion on this and if possible can you share the documentation.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

I assume by "mandatory" they mean that it's their policy to do it that way. It's hard to imagine any mechanical/electrical reason.

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14 E250 Bluetec "Sinclair", Palladium Silver on Black, 153k miles
06 E320 CDI "Rutherford", Black on Tan, 171k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

You said that you travel.

It should be easy enough go call a few Mercedes Dealers in differen locations and ask them what they charge for labor and what parts they would change.

Also becoming a Mercedes Benz Club of America Member usually gets you a discount. The amount of the discount seems to vary between Dealers but some have mentioned 10%.
The cost to be a Member is too steep for Me but if you have a fleet of Mercedes Cars and want to buy only Mercedes parts and have work done it could pay off.

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84 300D, 82 Volvo 244Gl Diesel

I could give that a try but I'm not sure what that would gain me. I suspect they have a standard labor rate list for each job and it is probably a condition of franchise by MB that they adhere to it. Hopefully enforced by "mystery shoppers".

I did get my 10% MBCA discount, parts and labor. That roughly paid for my last 3-year renewal.

If I was able to be home for a couple weeks straight I would have been more willing to take this on. More room for recovery from the unexpected when I'm not flying in on Friday night, and leaving out first thing Monday morning for several weeks in a row.

The fact that the plugs aren't just needed for cold starts also influenced the decision. Her MPGs dropped from the usual 21-22 to 18 on this last tank, I suspect the failed glow plug had something to do with it. She said it was really starting to run like crap before she was able to get it in to the dealer.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

I don't think replacing them all and the relay is mandatory, just a precaution. Sprinters seem to have a rough time with the relay but they use a different system and high voltage plugs (11V vs 7V).
I did not take pics or a video of the job, it was super simple and straight forward, not like working on a 617 diesel but like working on any other modern car-fragile wiring harnesses in the way, complicated ducting to remove, lots of fragile plastic parts. After a few years of heat cycling these are going to be very hard to work on! I should probably do the job again this summer, 60k miles have passed already this time I will try to shoot a tutorial if I remember!
I also had my egr valve out recently, nothing to worry about there it was whistle clean nothing like the photos that come up on google. Fuel quality and driving it easy is key I guess.
I do understand about having to get it done so it is reliable, we have an extra car so one can sit and wait until the repairs are made, I cannot afford to pay someone else these days I just don't make enough money. When I go on work related trips sometimes I am on the road for 30+ days in ski country, racking up 4000-6000 miles a month, reliability is key!

Nice Job. 600.00 well spent A little luxury is a nice thing every now and then. Taking my car to dealer reminds me of room service in a hotel.

I think the mandatory means that they have seen enough glow plugs and relays fail at that mileage that while they are in there, they know it is best for you if they replace them. And customers are not always smart enough to opt in for that when you suggest it and probably quick to complain when they have to come back in a month and pay for all that R&R labor again . So they make in mandatory because of stupid customers.

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

True enough - MBCA membership is steep, esp. if you never hardly use it to either attend events, buy a new MB, or buy parts very often.

I got around this years ago by having a B2B trade discount because of the automotive supply business I own. One MB dealer's disc. I have an account with was 15% or so. It definitely pays to pay rock bottom and get their parts delivered to my office as well.

I'd of done this job myself, and if I ran into trouble, I can always get some assistance from either some fellow MB diesel enthusiast friends of mine. However, most every job I've tackled as a DIY, has turned out well. Just luck, I guess.