Saturday, March 3, 2018

W123 Mercedes 240D Idle Test - Video

A well running W123 diesel should be very smooth. Over the years I have been told "they all rattle and vibrate, they always have, even new." 

I have had a hard time believing Mercedes-Benz would or could ever sell a car that vibrated as much as I have been told is "normal." Mercedes was up against high-end luxury cars in the United States and had to meet a fairly high standard of luxury and comfort regardless of whether or not it was a diesel.

With that in mind, I set out on a journey to see just what was necessary to make my 1981 240D run like Mercedes designed it to. With many checks and a number of maintenance items replaced, this car is once again running excellently and I am pretty convinced it is running close to factory if not at factory spec. 

It should be noted that the process of "tuning" should begin with a compression test. If that fails, no need to go further until that is rectified. 

The following test is usually performed on Rolls-Royce, but I thought it would be a great demonstration for a diesel, and the results truly surprised me. Prior to the work I performed, this glass would have bounced right off the valve cover.



2 comments:

  1. Hi
    Thank you for sharing your knowledge and experiences gained whilst working on these iconic cars.
    I’m seriously considering buying a W123 240D with 200k miles and would like to know what to check in order to avoid serious issues post purchase?
    I do intend to have a test drive before purchase.

    Kind regards

    Joe Conti England

    ReplyDelete
  2. Hello Joe,

    My sincerest apology for getting back to you over a month later. I am just now able to catch up on the extra curricular activities in life. I hope this response is not too late.

    I am going to write an article based on your question that will post this weekend.

    Thank you for visiting my blog.

    Kind regards,

    ReplyDelete