[W126 Coupe] Camshaft Snapped! Intermittant Rough Idle -Me too-HELP!

[airedale at sbcglobal.net]

The owner/mechanic ( a graduate mechanical engineer from Kansas University whose family has for many years and still does own a Mercedes Benz Dealership in his native Persia ) acted like this is not that unusual an occurrence in the 560 engine. I got that idea from him saying it always happens on the left ( drivers ) side. Another mechanic in the shop mentioned the valves could be bent depending on what position they were in because the piston continued to move. I did walk back after he said that and noticed in both cases they were not resting on the peak of the lobes or near the peak. Maybe because it happened at idle there was no inertia to continue spinning, I can hope to be so fortunate in light of this unfortunate incident..
John
  ----- Original Message ----- 
  From: Mister McGoo 
  To: mbcoupes at mbcoupes.com 
  Sent: Thursday, October 27, 2005 10:59 PM
  Subject: RE: [W126 Coupe] Camshaft Snapped! Intermittant Rough Idle -Me too-HELP!


  Geeze!  Does your mechanic have any idea of cause?  I have heard of a 420 camshaft breaking, but even that, I understand, was in conjunction with the timing chain jumping (I didn't see it).

  You say you had no compression on No.8.... valve open?  And then what about the piston? (Perhaps you don't know yet......)

  Any experiences from anyone else?  Rusty?

  -Bellamy



   


----------------------------------------------------------------------------

    From:  <airedale at sbcglobal.net>
    Reply-To:  Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
    To:  "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
    Subject:  [W126 Coupe] Camshaft Snapped! Intermittant Rough Idle -Me too -HELP!
    Date:  Thu, 27 Oct 2005 21:37:01 -0500
    >What a shock! Last Saturday I went into the Post Office and left my 
    >perfect running '91 560SEC idling with my lady friend in attendance. 
    >When I came out she said the car shook and then started running 
    >rough. I drove home with this low speed miss but the car could have 
    >gone as fast as I wanted on the highway. I called my mechanic Monday 
    >and took it in thinking some electrical or maybe the fuel system was 
    >amiss. He immediately isolated the cylinder closest to the driver 
    >and said it had no compression and thought perhaps a lifter had 
    >collapsed. I left the car there. He called this morning and said the 
    >left camshaft had snapped! I went there and sure as if it had been 
    >cut by a hacksaw blade the camshaft was in two pieces broke just 
    >ahead of the bearing journal before the last cylinder on the drivers 
    >side. I wad dumbfounded looking at this 1 inch steel bar that had 
    >snapped like a matchstick. He said in the 560 it always seems to be 
    >the drivers side camshaft that does this although in other cases he 
    >has seen it seemed to break farther forward. This is the first time 
    >on any car I have ever heard of a camshaft snapping. At this moment 
    >I do not like this German Masterpiece as well as I did.
    >John



------------------------------------------------------------------------------


  The MB Coupes Website!
  W126 SEC Mailing List
  Postings remain property of MB Coupes, L.L.C.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.pairlist.net/pipermail/mbcoupes/attachments/20051027/aca2c10b/attachment.htm