Hello too all and thanks for the help- So I am planning on buying a 1990 300D but the problem is that an Automatic temp valve, or something i dunno what it is called, it regualtes the the heater and controlls how much coolant gets heated up to make the heater work. It broke and now the car doesnt hold coolant. I cant find the part and dunno how much it would cost to fix- so could you tell me possibly what part it is? how much the part may be? where i may be able to get it? Thank you and hope to have a Bnz to join the forum with!!!! Thank you

 

You ought to contact the Mercedes dealer and at least get the name of the part out of them.
Take a pic with a digital camera and show it to them.

 

Sounds like what we call the monovalve on some of the older Benz's. Don't know if that designation goes for the newer models or not.

 

Thank you all that helped, mono valve sounds about rite- they said it was doing to be almost 200 dollars or i could get the core that has the part already installed for 350. I may just go with the core and get 2 new parts instead of having to replace it later on. Is there are good places/ Sites to order from besides the mercedes dealer, They are not being very helpfull to me, And would rather give my money to someone else. Thank you !! all

 

Check with Autohaus Az

http://www.autohausaz.com/

 

I would like to thank everyone that helped me out especially Diesel 9112 for every thing he/she did for me such as the diagrams and such THANK YOU EVERY ONE - I should HAVE the Diesel- on Monday Tuesday if i can get the part that soon, The car is in transition to me from the owner-he doesnt want to sell it to me till it runs- what a good guy - and for 2k on top of that awesome for me ithink and hope- Thats not bad for a 1990 300d turbo right 250k nice interior- let me know - Jsun And Thanks Again For the help EVERYONE you are all so nice!!!!