230 M115 engine head need rebuilding? - Mercedes-Benz Forum

 
LinkBack Thread Tools Display Modes
post #1 of 3 (permalink) Old 09-17-2011, 03:34 PM Thread Starter
BenzWorld Veteran
 
Rupununipete's Avatar
 
Date registered: Sep 2011
Vehicle: 1992 600 SEL x 3, 1998 E430 x 2
Location: SK, Canada
Posts: 680
Mentioned: 0 Post(s)
Quoted: 79 Post(s)
Garage
(Thread Starter)
Question 230 M115 engine head need rebuilding?

My (new to me) 1979 230C Coupe issues blue smoke ONLY at high speed when passing traffic.

The fuel consumption is goofy bad and I have a wee bit of blowback when I open the oil plug on the valve cover.

A compression test revealed 157#, 157#, 153#, 159# PSI from cylinder 1 thru 4.

Some of the valve adjustments are too tight to the cam lobes (I did not check all - only what was evident once I opened the valve cover box), but with no significant cam wear.

The inside of the engine has no varnish build up after 141,000 miles (211K kms) and there is evidence that the car has been serviced with AmsOil since forever.

I am going to assume that the valves have worn into the seats on the head, eliminateing the important valve lash and the guides are a little sloppy causing smoke at speed. Therefore the head needs rebuilding.

Can anyone agree, differ, tell me I am stuffed on my diagnosis or offer an opinion?

Pete
Rupununipete is offline  
Sponsored Links
Advertisement
 
post #2 of 3 (permalink) Old 09-19-2011, 02:02 AM
BenzWorld Junior Member
 
Date registered: Aug 2011
Vehicle: Various W114 coupes 250,280 (4), 350 R107, 250 W123, Alfa(s) 164, GTV6,
Location: New Zealand
Posts: 12
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
Is it smoking under high engine load in any gear? If so, we would suggest worn bores and/or piston rings. Our experience has indicated that the test for valve guides is the bottom of the hill trick when you put your foot down again and you get the puff of blue smoke. Blow back tends to indicate too much positive crankcase pressures, once again combustion gases leaking past the compression rings into the crank case. Obviously poor fuel consumption can be many things, but also supports worn bore/rings. Pull off the head, all will be revealled. You could adjust all the tappets and see if there is a change. thanks CMRL
CMRL is offline  
post #3 of 3 (permalink) Old 09-19-2011, 11:21 AM Thread Starter
BenzWorld Veteran
 
Rupununipete's Avatar
 
Date registered: Sep 2011
Vehicle: 1992 600 SEL x 3, 1998 E430 x 2
Location: SK, Canada
Posts: 680
Mentioned: 0 Post(s)
Quoted: 79 Post(s)
Garage
(Thread Starter)
Thanks for the comment CMRL.

I did not notice any smoke except @ high speed in top gear. I will have to run it out in 1st and 2nd gear range and see what transpires. Compression test came back at 153 to 158#.

I just replaced the transmission, but I am going to have to re-think the car now. Drop the money for the engine overhaul (top end at least), and still have underwhelming performance?

I am wondering how difficult it is going to be to slide a 420 driveline in it? Being that my differential will be needing attention at some point, it can be changed out at the same time.

I guess I have some research to do.
Pete
Rupununipete is offline  
Sponsored Links
Advertisement
 
Reply

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

Quick Reply
Message:
Options

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

Password:


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

Email Address:
OR

Log-in











  • 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



    Similar Threads
    Topic Author Forum Replies Last Post
    M115 engine misfiring makinfrenzinmybenz Vintage Mercedes-Benz 5 09-14-2011 07:58 PM
    Rebuilding the head Benzoid123 W123 E,CE,D,CD,TD,TE Class 11 11-08-2010 08:45 AM
    rebuilding cylinder head madmanmerc Vintage Mercedes-Benz 1 02-12-2007 07:41 AM
    spin on oil filter adapter for M115 engine? Gkase W123 E,CE,D,CD,TD,TE Class 2 05-27-2004 06:10 AM
    Which model uses M115 engine? Gkase General Mercedes-Benz 4 05-04-2004 04:11 AM

    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

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