On a -4degree Canadian winter day my s320 stays at 60 degrees at a standing idle, might creep up to 70. At highway speed it stays at 60 degrees. Is this normal for winter conditions for this engine or is this a thermostate problem, a DIY replacement. Where is the thermostat located on this engine, is it easily accessable.

Zibby

Change the thermostat asap!

60 is low.

Check out Tex's DIY for the 1996 E320

http://www.peachparts.com/shopforum/showthread.php?t=212906

While the year and series are different, the procedure should be nearly identical. He references photos in his article which for some reason I cannot see on my browser.

Hope that helps.

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Brian G.

1994 E320 Wagon with many warts SOLD
1995 E320 Wagon with a beauty mark or two FOR SALE

Zibby, I have had exactly that problem, my engine temperature did not go over 70 even after 20 miles of driving. At first I was (wrongly) happy about it because I thought it should be a good thing when the engine is not getting hot, since the purpose of the whole cooling system is to keep engine not getting hot.

After I replaced the thermostat the temperature climbs now to 87C just after 2 miles and remains stable there.

That was worth 15 bucks of part.

__________________
1996 E320 since 1/16/08, 171K miles as of Feb 2011

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1989 300CE - R.I.P. Dec 29 2007
Other MBs (sold): 1992 300E-24 - 1979 350SLC - 1984 230E - 1990 300CE

Thanks guys. The Pics sight was helpfull too.
I looked under the hood and the thermostate hosing was in plain view, real easy to get at. Have a new one on order will be in on Sat at which time I'll do the R/R.

Zibby

Thermostat in the engine is an 87C thermostat. A new one should bring the bottom end of the temperature into the range of 85C-90C.

__________________
Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record

Changed the thermostate in the 94 s320 on Sat., operating temp OK now. Job simple and esay.
I've included some pics.

1st pic. is of area / thermostat hosing to be removed.
2nd pic. is of 2 hoses removed and next to remove are the 3ea 10mm bolts and thermostat hosing comes off easily.
3rd pic. is with the old thermostat removed.
4th pic. is old thermostat.......reason for low operating temp.
Old thermostate hosing was in good shape, no corroded areas or warpage of flange, didn't need replacing so I cleaned it up with a wire wheel and reasembled with new thermostat and "O" Ring.
All of 40min worth of work and vertually no loss of fluid. Cost of new thermostat and "O" Ring.......$28. Canadian.
Now again a happy MB driver.

Zibby

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