Injector Seats Leaking
 

78 300D w/ low miles motor from a 80 300D swapped in

Got it started up for the first time after the swap and it runs great. Yay.
Then after the short test drive around the block it was smoking a little bit and I noticed lots of fuel and air bubbles leaking from where the injectors seat into the head.

Tried searching for this issue and couldn't find a whole lot of info.

Unfortunately I had to leave town and didn't have my 27mm socket with me so I couldn't pull the injectors. Trying to find out what the most likely issues are so I can be prepared when I return.

Answer
 

These links should help.

http://www.peachparts.com/shopforum/diy-links-parts-category/142405-diesel-injection.html

http://www.peachparts.com/shopforum/diesel-discussion/252429-diesel-cylinder-head-issues-thread.html



.

Didn't see anything related in either of those lists

Answer
 

You are describing:
* A pre chamber leak..
* An injector seal leak..
* A damaged injector body...
* A damaged cylinder head.


.

Looked through all those links again just in case, there's still nothing helpful. A couple threads on the OM603 with somewhat similar issues but pretty different, and a totally different head.
So, not much help.

I'm aware that those are the possibilities, I'm wondering what to look for when determining what the problem is? The car is in Portland and I'm not living there any more (long story lol) so I want to keep my trip up there as short as possible.

Could be just an improper torquing of the injectors too.

FYI
 

Home Made Special Tools, This is where members can share how they made special tools
http://www.peachparts.com/shopforum/general-information/239902-home-made-special-tools-where-members-can-share-how-they-made-special-tools.html

$15 REdneck Slide hammer and Prechamber adapter (Pics)
$15 Redneck Slide hammer and Prechamber adapter (Pics) - PeachParts Mercedes ShopForum

DIY 617.9XX prechamber tools
DIY 617.9XX prechamber tools - PeachParts Mercedes ShopForum

300 5cyl. homemade prechamber puller
300 5cyl. homemade prechamber puller - PeachParts Mercedes ShopForum

http://www.w124performance.com/service/W126/w126CD1/program/Engine/617/01-417.pdf


You have a 300D W123.130 1977-1981 OM617.912

there is no significant variation on the prechamber design/leak issues 1968 - 1985 covering the OM615, 616, 617.
The Procedure is essentially the same through some (not all) of the OM60x engines.

Injector + Heat shield + Nozzle, Prechamber + Collar, and Nailing. LINK THREAD
http://www.peachparts.com/shopforum/diesel-discussion/211750-injector-heat-shield-nozzle-prechamber-collar-nailing-link-thread.html

http://www.w124performance.com/service/W126/w126CD1/program/Engine/617/01-417.pdf

seal ring, Prechamber, standard size, x5 per engine
MB# 6150170060


seal ring, Prechamber, 2.3MM size, x5 per engine
MB# 6150170160

seal ring, Prechamber, 2.6MM size, x5 per engine
MB# 6150170260

seal ring, Prechamber, 2.9MM size, x5 per engine
MB# 6150170360



.

This will be a repeat of some stuff.

Sometimes people install the Injector Heat Shields upside down or do not replace them. If you drop them into the Hole the Heat Shields flip over one or more times.

Sometimes when the Injectors are removed the Prechamber Lock Ring/Retaining Collar loosens.
If that happens you are going to need a Special Tool to tighten the Lock Ring/Retaining Collar because the Torque on the Rings is fairly high.

The same theory applies to your Engine and the Newer ones with the exception that the Aluminum Headed Engine can sometimes develop a Prechamber leak even if the Lock Ring/Retaining Collar is not loose.

Also I took one of the Retaining Ring/Collar tools to the Junk Yard with me for testing and found quite a few Retining Rings were not nearly as tight as others. I do not know if they just loosen over time or it is from previous Injector removals.

Do you know if some one had recently had the Injectors out or Injectors rebuilt?

I'm not sure. As far as I know it was a good running engine removed from a car that was wrecked with only 160k miles. Then it sat for several months before getting installed into my car.

So, I guess good next steps would be:
-Remove injectors, check heat shields (they should be flat side down?)
-Torque retaining collars to spec (using special tool)
-Install new heat shields
-Torque injectors to spec
-Reinstall lines, bleed air, pray and hope!

No.

Ok, wasn't sure cuz flat side towards the injector makes more sense and that's what I thought I remembered. But then I read something somewhere, blah blah whatever
Thanks