Yes, it happened to me.My 82 300d has run @ 100c for a couple of months after installing new oem thermostat,radiator,hoses.Yesterday had to replace lower radiator hose so I decided to install a Mercedes brand thermostat.You guessed it.Now the temperature runs @ 85c.Both thermostats were set to open at 80c.Moral of the story-No more oem stuff for me on important parts like this!!Hope this helps.

__________________
Steve
91 300 SL (65K)
97 4Runner (85K)
82 300D (129K)
78 172 Cessna (2600 Hrs)
03 363GT Adams Tight Lie (Daily Driver)

OEM = Original Equipment Manufacturer
You may have been hoodwinked -- was the first thermostat a Wahler or not? Or, you may have had a defective thermostat.

Ron
http://germanstar.net

With OEM thermostats (behr) the car runs hot 95-100C+...with a AutoZone Whaler, it runs at a more acceptable 85 + or -.

__________________
1984 300TD Wagon, 407,800 mi (current daily driver)
1985 300DT Sedan, 330,000 mi (gone to that great autobahn in the sky)

Well, when the first thermostat was installed I broke a "Benz Rule",I could only find a advance store open and bought the OEM(Name brand unknown).You`re right it could of possibly been defective. Thanks for you`re input!!

__________________
Steve
91 300 SL (65K)
97 4Runner (85K)
82 300D (129K)
78 172 Cessna (2600 Hrs)
03 363GT Adams Tight Lie (Daily Driver)

Wahler is the OEM supplier for most Mercedes thermostats, not Behr.

Ron
http://germanstar.net

That may explain the " original equipment manufacturer VS original equipment manufacturer " title.... I just kept re reading that trying to figure out what it meant....

Classic case..

Behr makes the radiators in the USA cars. Not all Mercedes mind you- but the us market. They don't make thermostates for MB I'm told.

So they are an OE supplier- just not T-stats.

Man MB would make so much more if their dealerships were all decent!

Michael

__________________
Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E