[W126 Coupe] MBCOUPES Digest, Vol 25, Issue 6 noise in Helmuts engine

[Doug Gavin]

DW wrote:


>Yes, it's your timing chain, but before you replace it, check the chain

>tensioner on the right side of the engine.  When they get old they leak down

>too far (they work on oil pressure) which can cause a loose chain on

>start-up.  It's a good idea to change the tensioner when changing the chain

>anyway, so just start by replacing the tensioner and see if that doesn't

>cure the problem.

>

>Tom

>

>-----Original Message-----

>From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com]

>On Behalf Of Helmut Kern

>Sent: Friday, November 17, 2006 4:57 PM

>To: mbcoupes at mbcoupes.com

>Subject: Re: [W126 Coupe] MBCOUPES Digest, Vol 25, Issue 6

>

>Hi guys,

>I have a question and I hope someone has the answer.

>When my '86 560SEC is in the garage for about 2 weeks and I start it, the 

>engine sounds as if there is a bad bearing inside.I have checked the 

>alternator,the AC compressor and the water pump and they all sound ok.

>Could that be the timing chain?

>I am also looking for a passenger side seat plastic cover

>Thanks, Helmut

>

>

>The MB Coupes Website!

>W126 SEC Mailing List

>Postings remain property of MB Coupes, L.L.C.

>

>  

>

Just a thought for Helmut. It would be my suggestion that while Helmut 
is considering the tensioner he should seriously think about timing 
chain guide rails. I have seen two cars in the last two weeks, a  560 
SEL with a broken guide rail that was about to lead to disaster at 110 K 
miles and a S 420 with just 100K miles break a chain after several 
months of ignoring a clicking/ grinding sound, the guide rail had broken 
and the chain was loose enough to be striking the cover. The chain 
finally broke at 60 MPH after the broken guide rail got caught between 
the sprocket and the chain. The 560 $1700 and the 420 probably 
$5500-$7500 if it is not too far gone. It will probably be on e bay as a 
parts car.  I just had my 91 560 SEC rails, tensioner and chain replaced 
at 75K just to avoid disaster.  It's pay them now or pay them later or 
do it yourself if you can I guess. Good luck