W115 With M121 and Stromberg Carburetor - Mercedes-Benz Forum

LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 04-13-2015, 09:38 PM Thread Starter
BenzWorld Member
Date registered: Oct 2008
Vehicle: 1959 190, 1961 190SL, 1967 250SE 4Spd, 1968 220D 4spd
Location: SoCal
Posts: 146
Mentioned: 1 Post(s)
Quoted: 5 Post(s)
(Thread Starter)
W115 With M121 and Stromberg Carburetor

A guy I know has a 115 with an M121 (220) and the Stromberg carburetor. I've seen thousands of Mercs over the years, never come across one of these, and after some research, i'm beginning to understand why. Most retired Benz guys sigh after hearing about this oil-bathed stromberg, and the usual response is something like "tell him to look for another car"

Are there any alternatives to the Stromberg? The M121 is such a great engine, and the late 50s single solex was wonderful. In my opinion the thermostatic idle/mixture BS they started putting on carb'd benzes really put a dent in their longevity and reliability.

The issue with the car in question is that it will not accelerate. It will start, barely, and only with foot fully on the throttle. It feels like the accelerator pump on the carb (if it even has one?) has a torn diaphragm. The car has decent fuel pressure (using both the original mechanical, and an electric one I put in for diagnostic), proper spark, and good airflow (bypassed air filter housing entirely. I'd like to learn more about this stromberg if any posters have experience with it.
elduderino is offline  
Sponsored Links
post #2 of 4 (permalink) Old 04-14-2015, 07:37 AM
Premium Member
Date registered: Nov 2012
Posts: 1,241
Mentioned: 0 Post(s)
Quoted: 59 Post(s)
Premium Member
the early cars [ late 60s to early 70s ] had the uncomplicated version of that carb , there was no real bad issues about those , the later version had problems . remove the air filter boot , and with your finger , see if the piston moves freely up and down .if it does , remove the top housing [ 3 screws ] and see if the thin diaphragm is bad [ common ] .report here .
agillot is offline  
post #3 of 4 (permalink) Old 04-16-2015, 09:35 AM
BenzWorld Member
Kaelor's Avatar
Date registered: Apr 2015
Vehicle: 1970 W115 200/8
Location: Lima, Perú
Posts: 194
Mentioned: 1 Post(s)
Quoted: 24 Post(s)
I have a W115 with an M115 engine, is a 200. It comes with a Stromberg 175CD carb and I think they are not much difficult to repair. Actually I think that Aisan carbs are more complicated than this one.

The car belonged to my uncle but he never took good care of it, then it started having problems and shutting off. After like 3 years sitting there, he gave it to me cuz he wasnt gonna do anything at all with the car. So I openned up the carb and found that the diaphragm was torn. I think that is the only real problem on these carbs, but its really easy to assemble and disassemble so no worries...

I haven't finished with it cuz I'm broke and I'm rebuilding the entire engine too. I guess I'll post a thread to tell my story lol...
Kaelor is offline  
post #4 of 4 (permalink) Old 04-16-2015, 10:52 AM
BenzWorld Veteran
Bill A's Avatar
Date registered: Jan 2009
Location: So Cal
Posts: 667
Mentioned: 0 Post(s)
Quoted: 27 Post(s)
A real easy carb to fix and a pretty simple car as well but the parts can be expensive. Those diaphragms either got torn or just weaker and the performance would suffer to just stop. A small bit of tranny oil in the reservoir at service would help them last a lot longer.
Bill A is offline  
Sponsored Links

  Mercedes-Benz Forum > General Mercedes-Benz Forums > Vintage Mercedes-Benz

Quick Reply

Register Now

In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may 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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Title goes here

video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome