Hi , I have a 1983 300 SD and it seems I cant get hardly any heat out heater. It just blows lite warm air, The blower works fine but no heat.Is there a way to repair this or even make it so it blows hot air everytime I turn it on?

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1983 mercedes 300 sd 144 k

I would start off with the simple things like ensuring there is sufficient coolant in the system and no coolant leaks. Changing the thermostat is also a relatively inexpensive fix that you could try. Does the car run cool and is the operating temperature as per the gauge normal? You could have a defective auxiliary water pump or monovalve. There may be a fault within the controls for the climate control system.

300SD Heating Problem, HELP (I'm Cold)

First off thx for the quick reply:] I do have enough coolant and the car is running at normal Temperature. I had already replaced the climate control unit from one from the junk yard, It looked like a good one, Im thinking the monovalve my be the culprit, Ill try that next. Thank you again

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1983 mercedes 300 sd 144 k

I pulled out the mono valve and sure enough there was a tear in it. Im goin to the junkyard this saturday to see if I can find one

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1983 mercedes 300 sd 144 k