[W126 Coupe] Running warm

[Vedat Iplikci]

Pavel,

I know from experience (don't ask how) that these temp sensors are meant to function reliably when in contact with water. When the system somehow lacks water where the sensor is, the gauge will be unreliable. Though doesn't look very likely in your case, you might as well check out the possibility if your system has inconsistent coolant circulation. This might be caused by a pump with several fins broken, or maybe a partly clogged radiator.

Just my 2...

Vedat Iplikci
1987 560 SEC Euro
  ----- Original Message ----- 
  From: Mister McGoo 
  To: Pavel 
  Sent: Tuesday, October 10, 2006 6:54 PM
  Subject: RE: [W126 Coupe] Running warm


  Pavel;
   
  You are describing a temperature gauge that is malfunctioning.  Was the replacement temp gauge a known working one (like from another SEC?)  If so, you might have a connection or ground problem for the instrument.  Are all the other gauges (like fuel gauge) working OK?
   
  And yes, when a water pump is heading south, it takes a leak first.  This doesn't appear to be your problem because eventually you'd run out of coolant just moments before your engine cratered.
   
  A restriction in your radiator would cause your temp gauge to read hotter and hotter as though your thermostat was stuck closed, not jump all over the place.
   
  I'd look carefully at the gauge, the connections and wiring from the sensor. 

  -Bellamy



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

  > Date: Mon, 9 Oct 2006 15:08:40 -0500
  > From: zhur0002 at umn.edu
  > To: mbcoupes at mbcoupes.com
  > Subject: [W126 Coupe] Running warm
  > 
  >  
  > Hi
  > 
  > Have a new problem with my 380 sec.  Temperature gauge is acting weird. 
  > Keeps on running at 90 on freeway, than climbs past 120 than instantly
  > drops to 80.  Most of the time sits around 90.  Just put a new thermostat
  > in, still same story.  Changed the temp gauge no difference, changed the
  > temp sensor no difference.   Sometimes the temperature guage will stay
  > right at 80 for 20 minutes and then will start acting strange. Expansion
  > Tank seems to be under pressure.  If the gauge is showing 110 deg and I
  > shut the car off and right away put it in the on position it the temp gauge
  > displays 80.  As I shut the car off the gauge will peg out while the engine
  > is stopping. If I accelerate hard on the freeway it will drop the
  > temperature temp to 80-85 range. When I coast on a freeway do get back to
  > speed limit it will go back to 90-100 range.  If I turn the heat on it will
  > bring the temperature up I'm very confused.  Should I try a new radiator? 
  > Also I'm in minnesota and it is about 50 deg right now, car should run just
  > a hair above 80, like my 560 is.
  > 
  > Also noticed a coolant leak in parking lot after changing thermostat
  > thought it was came from the thermo housing when got home no leak
  > everything is dry with plenty of coolant left?
  > Pavel
  > 
  > The MB Coupes Website!
  > W126 SEC Mailing List
  > Postings remain property of MB Coupes, L.L.C.



------------------------------------------------------------------------------
  Be one of the first to try Windows Live Mail. 


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


  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/20061010/7d656610/attachment-0001.html