+1 for the gear wrenches and the magnet, good luck!

I'm not a mechanic (though I try), but what does the intake manifold look like, where is it, and how to get it off?

Thanks,

jeff

I don't have a picture of your engine, maybe someone else can post a picture showing the crossover tube and intake manifold. Without trying to sound critical (we all have to start learning somewhere), if you don't know where the intake manifold is or what it looks like, you might want to buy a book or ask someone for help in your area. It's not a difficult job, doesn't take special/expensive tools, but it would help to have a friend or a guidebook. The book that would be easiest to get would probably be the Haynes manual. It has come in for its share of criticism but it would give you the basics that you need to do the job.

Jeremy

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"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

How do we know if the glow plugs are the problem, or the relay? Until yesterday, the plugs were fine. Suddenly, no light when turning the key, and a rough start.

jeff 1991 300d, 127k

I reamed my glow plug holes.Carbon was burning up my plugs,also bought improved gp regulator.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Can you hear the relay click open when the glow cycle ends? If so, how long is the cycle lasting, assuming that the key is never turned to "start?"

Sounds to me like it could be the relay. I think if you lose the #1 GP or more than one is out, the light will not come on, but if they were fine the other day I'd bet on the realy .
My light stayed on for less than a second, and the relay shut off after 5 seconds..
World of difference once I got a new relay in there. You might be able to find a cheap used one on ebay.

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Dan
2005 E320 CDI - 246k
1987 300SDL TD05-16g, Herlevi pump, Elbe manifold, 2.47 LSD - 213k
Past: 1987 300D - 264k

Check and see if you are getting voltage at the plugs. That will tell you if the relay is bad. If you want to know which plugs are bad, if any, the best way is to pull each one and bench test it.

Scott

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Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

This is very wise advise

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1996 E300 110,000
1985 300TD 212,000
1980 300D 238,000

As said previously after the old Glow Plugs are out there is a tool called a "Glow Plug Reamer" to ream out the carbon build up (you can see them on Ebay also). If you do not want to get a Glow Plug Reamer do a search and find some Threads where alternative methods to clean out the Glow Plug holes are talked about.
Before you install the new Glow Plugs coat the Glow Plug threads with a Never-Seeze type compound; this will make it easier to remove them the next time.

The comment concerning the littl Nuts that hold on the wires is true; it is easy drop and never find them and some brands of Glow Plugs do not come with new nuts.

So far only the Bosch or Beru made Glow Plugs hold up well. In the US the Bosch plugs cost less.
I can attest to the fact that the Autolite Glow Plugs are no good. After 3 months use the tips swelled up on 2 of mine and I had a hard enough time trying to get them out that I was worried I was going to have to drill them out. Some of the Forum Members also claim the Monak made Glow Plugs are just as bad.

None of us were born Mechanics; it is an aquired money saving skill. Having a good Service Manual saves you a lot of time, money, heartbreak/frustsration/anger and physical pain.

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84 300D, 82 Volvo 244Gl Diesel

I lost all 5 overnight once, so dont assume it is the relay.
you should be able to hear it click, also a few basic electric tools will help- like a test lite and a multi-tester- dont have to spend a lot, $20 should set you up.

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.

1991 300 D -- no 80 amp relay fuse ? -

check harbor freight for a multi tester. bought one last month on sale for $2.67.

they should also have test lights. looks like an ice pick with a long wire on the other end and a alagator clip.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

1. On the "new" 124s, the nuts are captured so you can't lose them.
2. 124s have the pencil style plugs and from '90 on have afterglow, as Jeff stated.
3. 601s-603s don't typically have trouble with stuck glow plugs, that is the 606.

I'm with Jeremy on removing the crossover and intake. I replaced 2 plugs then a third without removing anything. When the 4th one went I did the other three by removing the intake. I decided to remove the first three and ream the holes as well. If you do remove it, you may want to order the plastic clips that hold the hard injector lines. The are usually pretty brittle after 18-21 years.

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1987 300TD 309, xxx 2.8.2014 10,000 mile OCI


Be careful of the toes you step on today, as they may be connected to the ass you have to kiss tomorrow. anonymous

“Be who you are and say what you feel, because those who mind don’t matter, and those who matter won’t mind.” Dr. Seuss

Just wondering, when I turn the key, the glow plug light might not come on. So if I try again, it might come on for a while. Does that mean it's the relay, or the plugs?

jeff