I recently discovered that the same sealing ring is used in at least three places on a '96/'97 W210 E300:

- Oil Drain Plug X1;
- Banjo bolt for upper transmission oil cooler fitting on radiator X2; and
- Coolant plug just behind the head's upper coolant hose fitting X1.

Oil Drain Plug Seal (14 X 20 X 1.5 mm)
Pelican Parts - European Automotive Parts and Accessories - Porsche • BMW • Mercedes • Volkswagen • Audi • Saab • Volvo • MINI

Attached Thumbnails

 

__________________
- Greg -
1973 220D, The Prodigal Benz
1974 240D

Slighly off-topic, but the coolant bleed screw pictured in the photo is not present on '98 and '99 models. Is there an alternate procedure for getting the air out of the '98+ engines?

__________________
1998 E300 turbodiesel

America's Rights and Freedoms Are Not The Enemy!

I'm not sure if that's a coolant bleed screw or a spare temp sensor port. I used that port to install a 91c temp switch to control the second aux fan I installed in place of the belt driven aux fan. Bye bye viscous clutch, you won't be missed.

__________________
CENSORED due to not family friendly words

That bolt is a remnant of the old casting of the 606 head, there is a sensor in that port when this cylinder head is used on the W124 model. That temp sensor is for the HVAC pushbutton control unit and is used to regulate blower fan speed until coolant is hot and to kickstart the condenser cooling fans at full speed if the coolant is about 225F.

There is no need for tiresome bleeding on this engine if you backfill it first.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Thanks. I noticed in your photo that the plastic securing clips for the high pressure fuel lines are broken. Without the clips, the hard lines will eventually crack and break from the vibration, and they're not cheap. Without the clips, they can also rub against each other, or parts of the engine, until they fail.

These are the clips you want, the engine takes a total of seven:

Pelican Parts - European Automotive Parts and Accessories - Porsche • BMW • Mercedes • Volkswagen • Audi • Saab • Volvo • MINI

Two of the seven are visible in your photo, both broken:

__________________
1998 E300 turbodiesel

America's Rights and Freedoms Are Not The Enemy!

There are many zip ties holding them together both on my om603 and om606. Once the fuel lines those are bent the plastic clips no longer work.

__________________
CENSORED due to not family friendly words

Sounds like you're at least aware of it then. Although I'm not sure how these fuel lines become bent. They're made of quite thick wall tubing. Old collision damage maybe, or improper R&R procedures?

__________________
1998 E300 turbodiesel

America's Rights and Freedoms Are Not The Enemy!

The hard lines experience 3000 PSI pressure pulses every time the cylinder is injected. The lines actually elongate and expand every time. If you don't have the lines correctly anchored in the clip and pad system, and they are touching other lines or the intake manifold, they will develop a worn area and leak. Or the line flexing causes fatigue at the ends of the line. They will develop a crack at the fitting and leak.

My 606 had zip ties holding the lines thanks to the prior owner. I had to replace a line not long after I bought it. I now have all the proper attachment devices in place.

__________________
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

Funny the twists and turns some threads can take!

I suspect even brand new fuel lines require a certain amount of fitting. I spent the better part of a day straightening out all the fuel lines on the '96's 606 so they would fit properly. It can be done, but it is a time consuming, patience trying PITA.

I had all the lines off while the injectors were serviced and did it then. For each line I started at the IP end and went through from there, adjusting each bend and and trying the fit, back and forth, back and forth, until they fit individually and also didn't rub/touch each other anywhere. Sometimes making them fit together required going back and redoing a line that was previously gone through. When finished each line's ends aligned perfectly with the fittings on the IP and the injectors, making installing them a snap. For me it was worth the time and gnashing of teeth.

One reason for lines getting bent out of shape might have to do with folks bending ends out of the way instead of removing lines completely when servicing delivery valves and injectors.

__________________
- Greg -
1973 220D, The Prodigal Benz
1974 240D