1983 Mercedes Benz 300td Heater issues

1983 MERCEDES BENZ 300TD
155,000 MILES • 5 CYL • TURBO • RWD • AUTOMATIC
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SSAVVY
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I am having issues with getting good heat sometimes I get good heat and other times i get cool air when i start the car and when i am driving and getting good heat it can change and blow cool air. I replaced the mono valve and now the temperature is going sky high and there is no circulation from the anti freeze could the problem be the aux water pump?
Nov 26, 2013 at 2:24 PM
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JACOBANDNICKOLAS
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I never heard the term, "Mono Valve". Can you explain exactly what that part is? I most likely know it as another term.
Nov 27, 2013 at 9:34 AM
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SSAVVY
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Mono valve is also called a Heater Control Valve.
Nov 27, 2013 at 1:37 PM
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JACOBANDNICKOLAS
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Okay, that makes sense to me. Do this for me. Start the engine, let it warm up with the heater on high. Feel both heater core hoses and tell me if both are hot or if one is hot and one cool.
Nov 27, 2013 at 4:42 PM
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DR LOOT
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sounds like the circulation pump located in the front right fender, right above the receiver drier, make sure you are getting power to it and check for vacuum leaks.
Feb 15, 2015 at 7:50 AM