Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 10-02-2012, 01:41 PM
Registered User
 
Join Date: Sep 2012
Posts: 204
1984 300D Injector leaking

I've driven this car 500 miles now trying to get use to any noise it is or will make after seating for 12 yrs. Initially I thought it was the valve cover gasket that was leaking, I sprayed the area with white gas so it will dry everything and revealed where the leak is coming from. After all the miles I put on, the leak is coming around the injector area. The injector seem to have some insert where it threaded into.

Can someone educate me how these injectors are installed on the head? If I remove the injector, the insert I am referring to, will that come out also having the right tool to unscrew it?

Attached Thumbnails
1984 300D Injector leaking-slide1.jpg  
Reply With Quote
  #2  
Old 10-02-2012, 01:50 PM
Registered User
 
Join Date: Aug 2007
Posts: 972
If I were you, I would replace my injector return lines and see if the leak doesn't stop. Chances of success are outstanding. Chances of the leak originating as you describe are almost nil.
Reply With Quote
  #3  
Old 10-02-2012, 01:51 PM
greazzer's Avatar
dieselfuelinjector.guru
 
Join Date: Sep 2010
Location: 2021 - The Great Florida Count-down
Posts: 6,379
X 2 ... most likely culprit is the return lines ...
Reply With Quote
  #4  
Old 10-02-2012, 01:55 PM
Stretch's Avatar
...like a shield of steel
 
Join Date: Sep 2009
Location: Somewhere in the Netherlands
Posts: 14,461
X3 on the return lines

In answer to the question about special tools - yes - searching for "pre-chamber removal tool" with or with out "home made" will bring up loads of information for you on this site (and others)

In answer to removing the injector - no the pre-chamber will stay in place - well it bloody well should do!

If you remove an injector you should replace the little heat shield that fits under it.
__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!
Reply With Quote
  #5  
Old 10-02-2012, 02:48 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,038
In the diagram #50 is the Ring that you are asking about that indeed needs a special Tool to remove.

That Ring does double duty. It is the Retaining Ring For the Prechamber by way of external threads and also the Injector threads into the Center of it.

In the pic I drew some orange lines. Those lines represent a space between the Injector and the Prechamber. What happens id when you have a leak the fluid seeps between the threads of the Prechamber Ring/Injector and fills that space.

When you run the Engine with it like that it looks like there is a Prechamber leak because you see some bubbles.
While it is possible for a Prechamber to leak in normal use Carbon Build up in the space around the Neck and there is empty area between the Prechamber and Head where the Prechamber gets wider; that also fills with Carbon an seals everthing.
I don't know for sure but I believe the bubbling is caused by the shock wave of the Fuel being injected and ignited.

When the actual Injector does leak it of most often between the upper and lower 1/2 of the Injector. Sometimes removing the Injector and re-torquing it solves the issue. More often you need to take the Injector apart and lap the precision surfaces inside of the Injector.

After that the little Fuel Hose Return Nipples are swedged/crimped into the upper Injector Body. Sometimes they become loose. No way to fix it but to replace the upper body.
Some people cut the nipple off and weld over the bad nipple area and move that Injector to last Cylinder where there is no need for 2 return Hose Nipples.

It also happens that sometimes the Fuel Injection Line that screws onto the Injector develops a crack or Pin hole.
Attached Thumbnails
1984 300D Injector leaking-glow-plug-prechamber-cut-away-sep.jpg  
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #6  
Old 10-02-2012, 04:13 PM
whunter's Avatar
Moderator
 
Join Date: Dec 2003
Location: Metro Detroit, Michigan
Posts: 17,416
Attention

Quote:
Originally Posted by WMO Madness View Post
I've driven this car 500 miles now trying to get use to any noise it is or will make after seating for 12 yrs. Initially I thought it was the valve cover gasket that was leaking, I sprayed the area with white gas so it will dry everything and revealed where the leak is coming from. After all the miles I put on, the leak is coming around the injector area. The injector seem to have some insert where it threaded into.

Can someone educate me how these injectors are installed on the head? If I remove the injector, the insert I am referring to, will that come out also having the right tool to unscrew it?
You have e-mail with attachments..


.
Reply With Quote
  #7  
Old 10-02-2012, 05:22 PM
Registered User
 
Join Date: Sep 2012
Posts: 204
Thank you everyone for the quick response the email with valueable information. the reason I use the white gas (coleman fluid) it does a good job in Neutralizing any petrolium base product, which leaves a dry and clean area. I sprayed the entire area with it, the fitting and the return line area are dry and all the wetness seen on the photo is coming from the (pre-chamber) fitting.

It seems to be a problem according to "mercedes source" tech, so now all I have to do is get a set of those "home made" tools and fix this. I read a lot of post with members making these special tools and selling them. those of you still making them and selling them, I am in the market for a set. I have the slide hammer to extract the pre-chamber.

Again thank you very much for everyone's input and Miss Doris thanking you as well.

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 05:07 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page