[W126 Coupe] RE: Camshaft Snapped

[John Helvey]

Thanks Sam,
The car is fine and for sure I am appreciating the H&R Springs now for more 
than just aesthetic purposes. The SEC seems to handle much better in mundane 
city driving now. The front shocks that came off were original and likely 
needed replacing anyway.
I showed the broken cam shaft to a mechanic friend today and his comment was 
they just had not developed heat treating as well back then ( 1991 ) as they 
have now. He thought because of some coloration in the surface of the snap 
surfaces that there had been a crack in the camshaft for awhile. He also 
speculated that there could have been a lubrication problem with that last 
Journal at some point as it snapped right ahead of it.
Best,
John

----- Original Message ----- 
From: "Sam Sisic" <ssisic at Antunovich.com>
To: <mbcoupes at mbcoupes.com>
Sent: Monday, October 31, 2005 1:05 PM
Subject: [W126 Coupe] RE: Camshaft Snapped


I've heard that a cam and or a crank shaft can snap in a back-fire
situation when a "geared" type timing set up is used in lieu of a timing
chain. I've heard this from a number of techs while in the process of
building up the motor in my Mustang. Of course, I went with a good
performance double roller chain after finding that out as chains have
some "give" in a back-fire situation preventing damage to those
components.
I'm not suggesting that this is what happened to John's cam... Just a
thought on what appears to be a very rare occurrence in the case of the
560 motor. It could have been a rare flaw in the casting of the cam
shaft itself, I dare say... Germans are people too. HA!
Anyway, great to hear you have all that repaired and back on the road
again John! I'm sure you're enjoying those H&R springs too! That's the
right set up.
Sam
------------------------------
Message: 2
Date: Sat, 29 Oct 2005 23:45:59 -0500
From: <airedale at sbcglobal.net>
Subject: Re: [W126 Coupe] Camshaft Snapped! Intermittant Rough Idle
-Me too-HELP!
To: "Mercedes Coupes Mailing Lists" <mbcoupes at mbcoupes.com>
Message-ID: <001001c5dd0c$d2e02c60$210110ac at JCH>
Content-Type: text/plain; charset="iso-8859-1"

Well the snapped camshaft turned out pretty well, the cam cost $359. and
the labor was $600. Slight additional material charges for 2 new oiler
tubes one for each side and 2 new valve cover gaskets. The engine is
running perfect again fortunately the valves on the #8 cylinder were
closed and no further damage took place. While there I also had H&R
Sport Springs all around and front Bilstein HD Shocks installed with
great aesthetic results and no loss in ride comfort.
John

Message: 5
Date: Sun, 30 Oct 2005 06:42:47 -0800 (PST)
From: A figment of the Imagination <figstir at yahoo.com>
Subject: Re: [W126 Coupe] Camshaft Snapped! Intermitment Rough Idle
-Me too-HELP!
To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
Message-ID: <20051030144247.47357.qmail at web31504.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1


Glad things worked out.  Like I had written and
predicted, it was unlikely you suffered a lot of
damage.  It's too bad you don't know what caused the
problem.  Hope it doesn't happen again.  There's
likely a small chance it will until the root of the
problem is cured. Did your mechanic ever tell you?

Happy driving!

-Figmented
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